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This FAQ is edited by: KeysCapt See Profile
It was last modified on 2014-04-01 14:13:00

1.0 About this FAQ

**PLEASE READ ** Before Submitting a Question

DO NOT post questions here that seek a response. That is the purpose of the forums and there is one where you can ask your question and get quick answers. You won't get them here, or by leaving feedback. The FAQs are for frequently asked questions that are applicable to many people.

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"I have ----- service, but it won't connect. Why?"
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"Why is my service doing this or acting like that?"
We want you to get an accurate and prompt answer. If questions like these are posted in the various forums on the site, they are seen almost immediately by our many expert members, and they will receive answers relatively quickly. This is also a better choice because if you're not sure of the answer, you can continue to discuss the issue and get additional help. Probably the best forum to start in, if you're not sure, is the General Questions forum. Don't worry ... if that doesn't turn out to be the best place, your question will be moved to a more appropriate forum.

How do I submit an item to the FAQ?

Simply click on the link that says, " I would like to suggest a question, and maybe also answer it, and add it to this FAQ" at the bottom of the page. You will be taken to a new screen, where you will see this information:
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Type the question you think should be added to this FAQ. (If you have an answer, type that in as well). Press PREVIEW and then SUBMIT.

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What is the difference between different catagories of ethernet cable?

Category 1 - It is an unshielded and untwisted wire. It has no rated frequency.

Category 2 - It is Unshielded and twisted into pairs. It has a rated frequency at 1 mhz. It offers an 100ohm impedance. We commonly use it for telephone systems

Category 3 - It is unshielded and twisted into pairs. It has a rated frequency of 16 mhz. It offers an 100ohm impedance. We commonly use it for telephone wiring and a 10Base-T connection (10 MBaud)

Category 4 - It is Unshielded and twisted into pairs. It has a rated frequency at 20 mhz. It offers an 100ohm impedance. We commonly use it for a 10Base-T connection (10 MBaud)

Category 5 - It is Unshielded and twisted into pairs. It has a rated frequency at 100 mhz. It offers an 100ohm impedance. We commonly use it for a 10Base-T (10 MBaud) and a 100Base-TX (125 MBaud) connection.

Category 5e - It is Unshielded and twisted into pairs. It has a rated frequency at 100 mhz. It offers an 100ohm impedance. We commonly use it for a 1000Base-T (125 MBaud), a 100Base-TX (125 MBaud) and a 10Base-T (10Mbaud) connection.

Category 6 - It is Unshielded and twisted into pairs. It has a rated frequency at 250 mhz. It offers an 100ohm impedance. We commonly use it for a 1000Base-T (125 MBaud), a 100Base-TX (125 MBaud) and a 10Base-T (10Mbaud) connection.

1. DSL 101

Why DSLReports?

Because it is the most user friendly place on the Web.
It provides the most informative Tools.
It provides the most Knowledgeable Individuals.
All in All. Its so easy to find the answers you are looking for.
submitted by 2kmaro

I heard DSL is cool. What is it?

DSL (Digital Subscriber Line) is an always-on internet connection that normally terminates in a socket on your wall, one that looks much like a phone socket. In the US, the socket is exactly a phone socket, and, for the popular residential DSL, (ADSL), the same housewiring does indeed carry both phone and data.

DSL is billed on a monthly basis, usually for a fixed price, and for the majority of providers it includes unlimited usage. In other words, whether you use it for email once a day, or you are a net addict and use it constantly, your bill is always the same.

Once you have a DSL line, you can use all the resources of the internet in the same way as you did from a regular modem and a dial-up account. The difference is now you can use them 24 hours a day with no connection delay, and usually (although not always) without a 'username' and 'password'. You need not worry about busy signals or any connection/disconnection process.

The key advantage of DSL over a dial-up modem is speed. DSL is from several to dozens of times faster than a modem connection. A complex web page that could take up to a minute to finish loading at 56K can appear in just seconds over DSL.

Connection speed, reliability, and the 'always-on' nature of DSL are the main reasons it is so popular. For small businesses, DSL is also a great way to save money compared to pay per minute ISDN service, or expensive T1 lines.


This is a question that is asked everywhere you look. Which do I want ... DSL or Cable?

DSL service shares bandwidth amongst ALL users connected to the same DSLAM. Cable shares bandwidth amongst ALL users connected to the same CMTS.

DSL's advantage?
The dedicated circuit prevents other users from affecting your connection to any significant degree. (In most cases.)

Cable's advantage?
Generally cable can support higher bandwidth rates, and can usually provide service to a larger area than 18,000 wire-feet, DSL's limit.

Cable modems are typically faster for downloads than most if not all DSL lines, when the cable infrastructure is new or well maintained. One of the most common complaints seen in our cable forums is that of increased latency and other problems as more subscribers in a given area come on line. Additionally, cable has a few other disadvantages when compared to DSL.

The first disadvantage is that cable is an RF network -- this means that it is vulnerable to transient problems "within the network" from RF interference. Since cable is a shared media, there is a possibility that performance may degrade over time as additional households plug in, connect additional devices (videos, game machines etc.) to the TV lines.

A cable company may react slowly to decreases in performance if it reacts at all, as they never sell access by speed, or promise consistent speed or latency.

Another of the disadvantages of cable over DSL is the upstream (return path). Cable companies are using a very narrow band for return signalling, and this is positioned below all the space allocated for TV channels. This band is prone to RF interference and is very limited in capacity. Upstream transmissions may therefore compete with others in the area, get delayed (suffer high latency) due to noise fighting techniques, and cable TOS (Terms Of Service) typically prohibit any kind of constant upstream use. Internet use is shifting away from central servers broadcasting to many individuals and some interesting peer to peer applications are appearing (games, voice and video applications, communal libraries). These applications need a strong upstream channel.

As the years have passed, the bottom line has basically evolved to personal preference or availability. Both DSL and Cable have their idiosyncrasies and consumer complaints. The best advice really is to check the various forums on this site which are relevant to the options available to you, and make an informed choice based upon what you learn. Ask questions in the forum ... there are some very knowledgeable members willing to help.

What is the fastest speed that DSL connections are capable of?

There are a lot of variables to consider with answering this question.

Typical residential offerings now usually have a maximum of 6.0 Mbps. Keep in mind that you will not normally see 6.0 megabits in a speed test ... due to overhead. However, one of our members reports some enviable residential speeds in Korea: (Aug '08)
"I just came from Korea and I had 1Gbps download AND UPLOAD VDSL residential service for about $47 a month. You can get 2Mbps/512Kbps in Korea for $2 a month if you pay a $10 installation fee for the initial service. It is common to find 100/100Mbps in Seoul with usenet, 7 eMail accounts with attachments up to 1GB, and dedicated webpages for about $28 for month to month with no contract. On Korea's national Internet site, I see that there is residential service available for 20Gbps, but I never saw any advertisements for that and I doubt that service that fast would be available outside the capital."

What's this about distance from the CO?

Maximum download and upload speeds?

The speeds above are the same factor for Upload as well. It's worth noting that some of your bandwith is eaten up by packet headers. Your upload and download speed are dependent upon each other, so if you use a lot of upload it can affect your download speed.

Note: 1 Kilobyte = 8 Kilobits.
Or, To calculate kilobits from kilobytes, "multiply" by 8. Example: 1 Kilobyte = 8 kilobits

What's this mean to me?

In the image above, the download speed is indicated in KBps. Using the chart, that translates to an actual download speed of around 1250 kbps, or 1.25 megabits.

For example: 1500 Downstream is equal to 1500/8 (1500 divided by 8) Which gives you 187.5KBps maximum downstream. Reaching That speed with a 1.5Mbps connection (1500kbps) is theoretically minimal, although you may come close.

DSL for Gaming?

DSL can be good or bad for online gaming depending on the ISP. It is recommended that you go to the /search section and make some selections (ie: DSLE, SurfCity), and research your choices thoroughly. (Read Reviews, pricing, check out the speed test archive and enter their Domain to see how the speeds are for users in your area.)

Also, get an idea what kind of pings you would see by posting a question in the forum relative to that provider. Others who game with that ISP will let you know what their experiences are. (Simple enough isn't it?)

Next, after you have picked out the best option for pings, take a look at pricing. Concentrate on the best speeds, the company's reliability, (don't want a poor quality company, or one that may not last) and shipping time. (Nothing worse than having to suffer from anxiety while awaiting DSL.

Done this way, you should hopefully have your DSL and a world of high speeds and reliability!

Can I FAX over DSL?

You cannot FAX over a DSL connection although says you can if you purchase their hardware, but you can still send and receive faxes over your regular telephone lines.

Upgrading to DSL may add a DSL modem of some kind, but if you keep your old modem, you can still use software fax products like winfaxpro. You simply use your telephone line as before, by plugging a telephone line into your dial-up modem as before. This holds true whether or not you get ADSL over your home phone or SDSL on another line.

You may also try the internet solution, and subscribe to a service like or which provides your own dedicated fax number, and you may send faxes using a utility, and receive fax messages (and voice messages!) in your mail inbox. You might also check out for a list of internet fax providers.

Latency versus Bandwidth - What is it?

One of the most commonly misunderstood concepts in networking is speed and capacity. Most people believe that capacity and speed are the same thing. For example, it's common to hear "How fast is your connection?" Invariably, the answer will be "640K", "1.5M" or something similar. These answers are actually referring to the bandwidth or capacity of the service, not speed.

Speed and bandwidth are interdependent. The combination of latency and bandwidth gives users the perception of how quickly a webpage loads or a file is transferred. It doesn't help that broadband providers keep saying "get high speed access" when they probably should be saying "get high capacity access". Notice the term "Broadband" - it refers to how wide the pipe is, not how fast.


Latency is delay.

For our purposes, it is the amount of time it takes a packet to travel from source to destination. Together, latency and bandwidth define the speed and capacity of a network.

Latency is normally expressed in milliseconds. One of the most common methods to measure latency is the utility ping. A small packet of data, typically 32 bytes, is sent to a host and the RTT (round-trip time, time it takes for the packet to leave the source host, travel to the destination host and return back to the source host) is measured.

The following are typical latencies as reported by others of popular circuits type to the first hop. Please remember however that latency on the Internet is also affected by routing that an ISP may perform (ie, if your data packet has to travel further, latencies increase).


Bandwidth is normally expressed in bits per second. It's the amount of data that can be transferred during a second.

Solving bandwidth is easier than solving latency. To solve bandwidth, more pipes are added. For example, in early analog modems it was possible to increase bandwidth by bonding two or more modems. In fact, ISDN achieves 128K of bandwidth by bonding two 64K channels using a datalink protocol called multilink-ppp.

Bandwidth and latency are connected. If the bandwidth is saturated then congestion occurs and latency is increased. However, if the bandwidth of a circuit is not at peak, the latency will not decrease. Bandwidth can always be increased but latency cannot be decreased. Latency is the function of the electrical characteristics of the circuit.

Why is distance important with DSL?

If you have heard even something about DSL, you will have heard about distance. Your phone lines normally terminate at a telco office, usually nearby. This distance, (the length of your line between your location and the telco office), is a very important factor in whether or not you can get DSL, and what speed you can get. The gauge of the copper lines may also be a factor.
Here are some rules of thumb for distance ranges. Please be aware that especially with non Telco ADSL lines, distance limits for speeds can vary widely from company to company. There are cases where it is policy for "residential" DSL lines not to be offered as far out as functionally identical "business" products!

The subject of distance and DSL is so important, we've added a special page for it, check this for detailed distance information per DSL network : Distance charts.

Note: The information below is not recent, and is probably not accurate any longer.

In Feet
less than 5000You will have little trouble getting all speeds of DSL
5000-10600You may have trouble getting the highest speeds on offer
10600-15000The danger zone for DSL from national CLECs like Covad and NorthPoint. Speeds on offer are pinned back steadily until they reach 192k for 15,000 feet. If your line is longer than around 15000 feet, they may not accept an order.
15000-18000In this range, Telco ADSL is normally still available, although it may be restricted to 300-500k speeds
18000-22000Telco ADSL is not available, although in a few areas, RADSL may be a product you can get. RADSL is speed-variable.
Some smaller DSL specialist CLECs may have solutions for you.
22000-28000Using less commonly used DSL equipment, it is still possible to use lines of this length.
18000-28000IDSL is an alternative or possibly the only alternative. IDSL is 144k/sec, about four-six times modem speed.
28000-38000IDSL is the only alternative

PLEASE NOTE: I did not write the original material here, I simply updated the FAQ with info that was relevant at the time, around eight years ago. If you have updated valid info please use the link at the bottom to submit your remarks and updated info.

Do I still need an ISP with DSL?

When you have a DSL connection, you also have an IP address. Consider this to be like your house address. The allocation of this address, and responsibility of delivering packets from the internet to your address, is normally the job of an ISP. (Internet Service Provider)

The quality of your ISP will be a big factor in how good your DSL performance is, how reliable it is, and how much technical support you can get when you have problems.
You are free to use an ISP as just an on-ramp to the internet, (including ignoring any email facilities they would provide for free, or their usenet news servers, or their home page disk space) but these services are available should you need them.

If you get ADSL from the phone company, you may find they strongly suggest using their own ISP (for example, Pacbell has, Bell Atlantic has, and that may be the simplest choice for you.
However, with the large number of internet 'service companies' providing everything from mail (hotmail etc), DNS ( etc), web hosting, news (supernews, dejanews etc), it is possible to be almost totally independent from the ISP, once your connection is up and running.

Apart from the Telco, the companies building large DSL infrastructures do not want to deal with residential customers directly, recognizing that this is often expensive and not their forte. So what they do is sell their lines to traditional ISPs, who now offer DSL, or to newer DSL-only ISPs, who are more marketing oriented.

The ISP provides your gateway to the Internet. When data leaves your house, it is not immediately on the internet. Instead it travels to your ISP first, and then to their internet gateways (known as upstream providers). The ISP provides DNS service for your static IP address, if you were a small business, or handle allocation of dynamic IP addresses (DHCP) otherwise. They would also provide you with email, a usenet server and more IPs if you need them. They are also the first point of contact for installation, billing and technical troubleshooting. Pick a good one! (which is what this site is all about).

Can I continue to use AOL?

Yes. AOL has a product called "Bring your own access", which for $14.95 a month (pricing as of 2002) lets you use the familiar AOL environment, from any internet-connected PC, including over DSL and through from another ISP. You will end up paying a little more than you would if you just used the straight internet, and you are getting billed by two parties -- your ISP, and AOL ... but if you wish continuity with your AOL account, this would be the way to go.

The AOL connection screen allows you to select another connection profile that assumes existing TCP access (a DSL connection), and does not attempt to use the modem to dial AOL. Once you set that up, you can change your pricing plan to move down to the bring your own access option.

AOL also is offering "AOL Plus", which is AOL and a DSL line all in one. They are slow to pick DSL partners, so availability of AOL Plus is limited right now.

To check AOL Plus availability, go to Keyword:DSL and click "Sign Me Up". Warning: AOL Plus involves an activation fee at present, and is only available if you are prepared to pay the $21.95/month unlimited access plan, plus the $20/month DSL plan. AOL Plus is not currently available to Macintosh users.

See /faq/3055 for additional information.

My email is with MSN/AOL - Can I keep it?

Almost any popular email accounts (hotmail, MSN, AOL) can be accessed from anywhere, with the appropriate mail client setup, or via the web.

AOL has the bring your own access option for external use of AOL via another (DSL) provider. Earthlink email can continue to be used without any reconfiguration, as can many other ISPs including MSN.

Once you get your DSL line, you can continue to use and maintain your old email account, if you continue to pay them.

Although rules for different mail systems differ, you may find you can purchase a minimum (MSN or AOL or Earthlink etc) plan that still allows full use of your mailbox, or email could be set to forward to your new address, while you tell people about it.

Can I connect my phone to DSL also?

Your phone signal can run over an ADSL line. ADSL is a type of DSL pitched for residential use. (See splitter or filter in the knowledge base for more information on ADSL and phones). This can be more convenient, and in some cases, remove the need to do inside wiring, since you can nominate an existing number for conversion to ADSL. This form of ADSL is currently almost exclusively offered by the Bell Operating Companies. CLEC xDSL, such as the range from Covad, is currently offered as a dedicated line only, although this form of ADSL is required by the FCC to be implemented by the ILECs and the CLECs soon.

There have been reports of interference problems between data and phone with ADSL lines -- a phone call may cause a data connection drop, or there may be unacceptable noise on the phone lines. This is usually related to the usage of microfilters, but not always. If you do have this problem, you will probably have to get your local phone company to install a splitter on the phone box at your house to fully separate the DSL and voice signals within your location.

There is one other situation where voice is actually run over DSL, and this is called VoDSL. The largest current implementation of this is Sprint ION, where a phone gateway that puts your voice and internet service over DSL, but the deployment of this version is very limited.

Do I need another telephone line to use DSL?

That answer to this question is maybe. It usually depends on your local telephone company and DSL technology.

In the majority of circumstances, the answer is "no"; A single phone line is all that is required (i.e. line-sharing). ADSL operates at a different set of frequencies than standard voice telephones. The difference in frequencies allows both voice traffic and IP (internet) traffic to co-exist on the same physical phone line. You simply need to obtain line filters (usually provided by your chosen service as part of your setup package) to plug in to the wall jacks you wish to use for normal voice telephones.

Unfortunatly, in a few areas with different types of DSL (such as SDSL), the answer may be yes.

Will my MAC work with DSL?

The Macintosh computing platform accesses the internet through the same protocols that the Windows computing platform does. This means that theoretically, any type of internet service Windows computers can use, the Macintosh can as well.

Two things to watch out for: One is the hardware. The DSL modems require your computer to have an ethernet card installed, and some computers don't have them already. If yours doesn't have one already, many providers will give you one to install. You'll have to make sure that it is Macintosh compatible (most are). The second is the software. Most providers will have the software to get you connected, but you'll have to ask them for it specifically, or else they'll probably assume you're on a Windows machine.

See /faq/allthingsmac for more.

edit: User tigirius says "All macs from the original iMac of 1998 until now are equiped with a DSL compatible 10/100 Port".

How long does it take from order, to install?

Dslreports ran a poll on this. It can vary widely, from a week in some parts of the country, up to 2 months or more, depending on what kind of problems there are between the DSL provider and the telco and the ISP. Obviously with time, the install process becomes more routine, and the delay drops. In some telco areas with straightforward ADSL installs, the whole setup can be done inside a week.

A good suggestion is to identity who your potential provider will be, and ask in the appropriate forum here on the site. Current users will have a good idea of what to expect for install times.

Does anyone have to visit my house?

Not necessarily. If you do not get DSL from the Telco, the telco may still have to provide the (new) copper line, then the DSL providing company (CLEC) comes to do any necessary inside wiring. In many cases, the communication between the Telco and the CLEC (Covad, Northpoint etc), is not great, and the line cannot be found, or is not left sufficiently close to the premise, necessitating further visits and delays.

For Telco ADSL, however, an existing line can be converted to an ADSL line, and the Telco normally has an "install yourself" package where they ship you the necessary materials, provision your line, and you simply hook up your modem and computer. In some cases, they might have to visit to install a splitter or a filter, and/or upgrade the NID (which is the phone junction box in your premise. See this for examples of different NIDs).

Puerto Rico Telephone Company offers DSL service under the name PRTDSL and offers user-installed ADSL. Their normal procedure is to qualify and convert the copper line and send you the ADSL modem by mail. You are still responsible for providing a NIC or USB port for the modem to use.

For more, see the glossary on installation.

I live in an apartment, not a house. Can I get DSL?

You should be able to get DSL service provided by the local phone company assuming your lines support it, and soon from CLECs once their line sharing agreements are in place in most apartment buildings. Whether you can get DSL that needs to be run over a separate copper pair depends on whether the apartment building management will allow a new copper pair to be installed into the phone box along with the wiring up to your apartment.

Can I get DSL with no phone service?

It may be hard to order DSL, whether it is ADSL from the telco, or SDSL, ADSL or IDSL from an ISP, without existing phone service, generally because the phone company may be reluctant to deliver a clean copper loop to a premise that they do not already have "in their systems" as a result of providing prior phone service.

This may vary from region to region depending on the particular local phone company involved.
One provider that does currently (3/07) offer this is AT&T under the name of AT&T Yahoo! High Speed Internet Direct.

Once you GET non-telco DSL on another line, it may be possible to cancel your local phone service.
Cancellation may be harder or impossible if you are getting, or have got, DSL over your same phone line (Telco ADSL or line-sharing CLEC ADSL).

Why is DSLR a good place to check your speeds -vs- Company site/ FTP?

DSLR is a more realistic representation of how your computer will work on a given connection out across the internet versus a ISP provided location because most ISP's have their test site/FTP within/under 3-5 hops, and often right after their edge router. This is done to reduce latency time and show you your connection to and from them, which is great, if that is your goal or your question is how fast you are connected to them. But if you want to see realistic tests DSLR is quite often 12-20 hops away, similar to the sites we go to and see every day.
submitted by pivoman

What is a dry pair ?

A dry pair is a pair of telephone wires that does not have regular voice on it, thus no dialtone. It is a dedicated line usually used for internet. Dry pairs are now found in SDSL, ISDN, IDSL, or a T-1 type service.

The following clarification submitted by NickNielsen
It is true a dry pair does not have dial tone, but a dry pair does not have any battery on it by definition. A wet pair has battery present on it.

There are several applications for a dry pair. A T1 is not a dry pair in the sense used. Indeed, a T1 opposite of the customers side of the network is hardly ever dry. It will commonly have 120VDC which is used to power remote repeaters for the T1 circuit depending on its length. The T1 network interface will isolate this high voltage and bring the signal to a much safer level. This is the reason the CSU/DSU has a Line Build Out (LBO) setting maximum of just over 600' from DMARC. It may not reliably work past that distance from the CSU/DSU.

This point might have been confused with the fact that any T1 provisioning requires removal of load coils from the existing cable, which are used to balance the freq response for voice freqs. These coils also block the higher freq that T1 uses. So when one asks for a "dry pair" for data application, it should also be "unloaded", otherwise it will not pass the high freq for the data.

A DSLR user adds this note:
In southwestern Ontario, dry loops (or pairs) do have a dial tone. This is so we can call the Bell# that identifies the number you are calling from. It's important to make sure you have the right pair when a company has 10+ copper lines. You can always try calling a regular local number and if it is a dry loop, it will tell you that the line must be activated. These lines are owned by Bell Canada.

1.05 Broadband Terminology


(Asynchronous Transfer Mode) A method used for transmitting voice, video, and data over high-speed networks. ATM uses continuous bursts of fixed length packets called cells to transmit data. Commonly referred to as the "ATM Cloud"

Bridge Tap?

Bridged tap or bridge tap is a long-used method of cabling for telephone lines. One cable pair (of wires) will "appear" in several different terminal locations (poles or pedestals). This allows the telephone company to use or "assign" that pair to any subscriber near those terminal locations. Once that customer disconnects, that pair becomes usable at any of the terminals. In the days of party lines 2, 4, 6, or 8 customers were commonly connected on the same pair which appeared at several different locations.

DSL can be affected by bridged tap. It depends on where the bridged tap is located ... the farther away from the customer's location, the better.
DSL signal reflects back through the cable pair from the end of a bridged tap, much like a tennis ball against a brick wall. The deflected signal is now out of phase and mixed with the original. The modem receives both signals and gets confused. This is when you "take errors" or cannot sync. If the bridged tap is long, by the time the signal bounces back, the original signal is far ahead and more powerful. Therefore, the modem will ignore the weaker signal and shows no problems.

Almost every cable pair in the world has bridged tap on it, so it definitely isn't always a DSL killer.
This FAQ entry updated by nunya01

BPS (Bits Per Second) ?

In data communications, bits per second (abbreviated bps) is a common measure of data speed for computer modem and transmission carriers. As the term implies, the speed in bps is equal to the number of bits transmitted or received each second. The bandwidth of a signal depends on the speed in bps.

CAP and DMT?

CAP and DMT are two different "flavors" of DSL. CAP uses two channels to connect and DMT uses 256 channels to connect, giving it a greater connection range and making it easier for it to adapt to certain line issues.

CIR (Committed Information Rate) ?

In frame relay networks, a committed information rate (CIR) is a bandwidth (expressed in bits per second) associated with a logical connection in a permanent virtual circuit (PVC). Frame relay networks are digital networks in which different logical connections share the same physical path and some logical connections are given higher bandwidths than others. Because the CIR is defined in software, the network's mix of traffic bandwidths can be redefined in a relatively short amount of time.


Pronounced see-lek. A Competitive Local Exchange Carrier is a telephone company that competes with an Incumbent Local Exchange Carrier (ILEC).

With the passage of the Telecommunications Act of 1996, there has been an explosion in the number of CLECs. The Act allows companies with CLEC status to use ILEC infrastructure.

Also see /faq/6789.


Customer Premise Equpment. This is the router or DSL modem that connects your PC, to your DSL line. The CPE is usually bundled with your DSL line. CPE may require (but not include) a NIC. (Network Interface Card).


A Digital Subscriber Line Access Multiplexer (DSLAM) is a network device, usually at a telephone company central office, that receives signals from multiple customer Digital Subscriber Line (DSL) connections and puts the signals on a high-speed backbone line using multiplexing techniques. Depending on the product, DSLAM multiplexers connect DSL lines with some combination of asynchronous transfer mode (ATM), frame relay, or IP networks. DSLAM enables a phone company to offer business or homes users the fastest phone line technology (DSL) with the fastest backbone network technology (ATM).
Also check : » ··· LAM.html


Data Link Connection Identifier)

The number of a private or switched virtual circuit in a frame relay network. Located in the frame header, the DLCI field identifies which logical circuit the data travels over, and each DLCI has a committed information rate (CIR) associated with it. The DLCI number is local to the FRAD and frame relay switch it connects to, and it is generally changed by the switch within the network, because the receiving switch uses a different DLCI for the same connection.

DNS (Domain Name System) ?

The domain name system (DNS) is the way that Internet domain names are located and translated into Internet Protocol addresses. A domain name is a meaningful and easy-to-remember "handle" for an Internet address.

Download? Upload?

Download is the process of information coming from someplace else to you. When you browse to a web page, you are "downloading" that page. When you get a file from some place on the internet, you are downloading that file.
Upload is the process of sending information from your computer onto the internet. The most common upload for most users is the simple request to "download" a new web page.
submitted by 2kmaro


Historically, the wire that "drops" from a telco pole. For DSL, the terminal point of the DSL line outside the building or premise.

EULA (End User License Agreement) ?

An End User License Agreement (EULA) is a legal contract between a software application author or publisher and the user of that application. The EULA, often referred to as the "software license," is similar to a rental agreement; the user agrees to pay for the privilege of using the software, and promises the software author or publisher to comply with all restrictions stated in the EULA.

F1 pair?

Often a CLEC reports the ILEC has 'facilities' issues and cannot provide an F1 pair to the CLEC. F1 (first facility) pairs refer to the usually buried pair bundles which go from the Central Office to the Cross Box. F2 cables (second facility) are the ones usually aerial, that leave cross boxes.


A distributed filter, or micro-filter, is a small electronic component that fits between your phone line and a regular voice device, such as a phone, a fax, or any device with a regular modem such as a cable box, alarm system or digital TV.

When DSL (ADSL) is provided over voice lines, all devices in the house except the DSL modem must be connected through filters. The filter protects the phone devices from high frequency noise. They are low-pass filters. The filter is also there to protect the DSL signal from being contaminated by high frequency noise added by analog phone devices, answering machines, etc.
Above by 2kmaro See Profile

Note: rcnetguy See Profile reports a problem with filters when a power strip is used:
said by rcnetguy:
We had tried to set someone up with DSL and they had no connectivity b/c they set up the filter into the power strip. We set the line away from the strip and it worked just fine.

FOC date?

Firm Order Commitment. The date at which outside wiring is scheduled (and the order becomes "real"). The normal procedure for a DCLEC DSL install, is for the Telco to schedule a FOC date to your MPOE (minimum point of entry). The ISP should advise you of your FOC date, (if one is required), as you may have to be there to let them have access.

Fractional T1 / T3 ?

A fractional T-1 or T-3 line is a T-1 or T-3 digital phone line in the North American T-carrier system that is leased to a customer at a fraction of its data-carrying capacity and at a correspondingly lower cost. A T-1 line contains 24 channels, each with a data transfer capacity of 64 Kbps. The customer can rent some number of the 24 channels. The transmission method and speed of transfer remain the same.

Frame Relay ?

Frame Relay is a high-performance WAN protocol that operates at the physical and data link layers of the OSI reference model. Frame Relay originally was designed for use across Integrated Services Digital Network (ISDN) interfaces. Today, it is used over a variety of other network interfaces as well.

Frame Relay is an example of a packet-switched technology. Packet-switched networks enable end stations to dynamically share the network medium and the available bandwidth. The following two techniques are used in packet-switching technology:

Variable-length packets

Statistical multiplexing

Variable-length packets
are used for more efficient and flexible data transfers. These packets are switched between the various segments in the network until the destination is reached.

Statistical multiplexing techniques control network access in a packet-switched network. The advantage of this technique is that it accommodates more flexibility and more efficient use of bandwidth. Most of today's popular LANs, such as Ethernet and Token Ring, are packet-switched networks.


FTP - File Transfer Protocol

A method of server and obtaining files to and from the internet.
Common FTP software include CuteFTP and WSFTP.

Ground Block

The ground block is where the coax cable from the Cable Company attaches to your house.

It generally should be near your power meter, and grounded to it (to prevent lightning from coming in through the cable line).

Usually, anything after the ground block is your responsibility. The ground block itself and anything before it is the cable company's responsibility.

It is illegal to unground the ground block. Most utility companies will put a bright yellow tag saying that the line MUST be grounded and to call them if you have to make any changes to it.

High Pass Filter

A high pass filter is a tiny device attached to your cable line to block anything below a certain frequency. A 50MHz HPF would block anything below 50Mhz.

This can be used to prevent very low frequency interference, or to block unauthorized cable modems from attempting to contact the head end, or even to remove TV service from your line while leaving HSD up.

For example, if your cable modem is to talk back to your provider at 29.5Mhz, and this HPF was on your line, your provider would never hear it, because it's below 50Mhz.

If you are having interference on your TV channels while online, try putting a HPF on the TV lines at the splitter. Do NOT filter your cable modem line or you will kill your connection.

I've seen HPFs that run from 50MHz up to 550Mhz.


Pronounced eye-lek. Short for incumbent local exchange carrier. An ILEC is a telephone company that was providing local service when the Telecommunications Act of 1996 was enacted. For example: GTE, SWB, AT&T. See also /faq/6788.

IMAP (Internet Message Access Protocol) ?

Internet Message Access Protocol (IMAP) is a standard protocol for accessing e-mail from your local server. IMAP (the latest version is IMAP4) is a client/server protocol in which e-mail is received and held for you by your Internet server. IMAP requires continual access to the server during the time that you are working with your mail.

KBPS (Kilobits Per Second) ?

Kbps stands for kilobits per second (thousands of bits per second) and is a measure of bandwidth (the amount of data that can flow in a given time) on a data transmission medium.

Higher bandwidths are more conveniently expressed in megabits per second (Mbps, or millions of bits per second) and in gigabits per second (Gbps, or billions of bits per second).


LAN stands for "local area network" & is a group of computers and associated devices that share a common communications line or wireless link and typically share the resources of a single processor or server within a small geographic area (for example, within an office building).

Usually, the server has applications and data storage that are shared in common by multiple computer users. A local area network may serve as few as two or three users (for example, in a home network) or many as thousands of users.


LATA (local access and transport area) is a term in the U.S. for a geographic area covered by one or more local telephone companies, which are legally referred to as local exchange carriers (LECs).

A connection between two local exchanges within the LATA is referred to as intraLATA. A connection between a carrier in one LATA to a carrier in another LATA is referred to as interLATA.

InterLATA is long-distance service.


For a terrific explanation of latency, see »DSL FAQ »Latency versus Bandwidth - What is it?

Line Tap Splitters (DC taps)?

DC Taps are special types of splitters that lose a ton of signal on one leg, but very little on another. The model number generally determines how great the larger loss number is.

For example:

DC-4 Tap: Loses 4db on one leg, around 1db on the other.
DC-6 Tap: Loses 6db on one leg, around 1db on the other.
DC-9 Tap: Loses 9db on one leg, around 1db on the other.

These splitters have one leg labeled "tap", and the other "out". The "tap" leg is the one with a large amount of loss.

Load Coils?

Loading coils are used to extend the range of a local loop for voice applications. They are inductors added in series with the phone line which compensate for the parallel capacitance of the line.

They benefit the frequencies in the high end of the voice spectrum at the expense of the frequencies above 3.6kHz.

Thus, loading coils significantly distort xDSL frequencies and must be removed for any DSL operation. They are often found at loops extending farther than 12,000 ft.

Local Loop ?

In telco, a local loop is the wired connection from a telephone company's CO (central office) in a locality to it's customers' telephones at homes and businesses.

This connection is usually on a pair of copper wires called twisted pair. The system was originally designed for voice transmission only using analog transmission technology on a single voice channel. Today, your computer's modem makes the conversion between analog signals and digital signals.

With Integrated Services Digital Network (ISDN) or Digital Subscriber Line (DSL), the local loop can carry digital signals directly and at a much higher bandwidth than they do for voice only.

Mbps ?

Mbps stands for "megabits per second" and is a measure of bandwidth on a telecommunications medium. Depending on the medium and the transmission method, bandwidth is sometimes measured in the Kbps (thousands of bits or kilobits per second) range or the Gbps (billions of bits or gigabits per second) range.


MPOE (Minimum Point Of Entry)

Local Carriers are responsible for bringing lines to the Minimum Point Of Entry (MPOE) for multi-dwelling business, high-rise, and apartment buildings. If the line is brought to the MPOE by the local carrier (ILEC - Incumbent Local Exchange Carrier), the CLEC (Competitive Local Exchange Carrier) is responsible for finding and wiring an available pair from the MPOE to the Customer Premise Equipment (CPE, AKA Router) location.

MPOE's are also referred to as NIDs and DMARCs.

Noise Margin?

Noise may be defined as the combination of unwanted interfering signal sources whether it comes from crosstalk, radio frequency interference, distortion, or random signals created by thermal energy. Noise impairs the detection of the smallest analog levels which may be resolved within the demodulator. The noise level along with the maximum clip level of an analog signal path set the available amplitude dynamic range.

The maximum data rate of a modem is limited by the available frequency range (bandwidth) and signal-to-noise ratio (SNR) which is amplitude dynamic range. If more of either is available, more bits may be transferred per second. In an audio analogy, the better (higher) the signal-to-noise ratio is, the easier it is to 'hear' the desired signal above the noise. The same principle applies here. The better the margin (the difference between the signal and the noise) the easier it is for your modem to pick out the DSL signal from the background noise.


PING: A protocol (command) that sends a message (packet) to another computer and waits for acknowledgment, often used to check if another computer (host) on a network is reachable.

It has been said that PING stands for "Packet Internet Gopher"


POTS stands for Plain Old Telephone Service.
Is sometimes used in talking about Upgrading/Testing your POTS line to support DSL.


Point To Point Protocol over Ethernet
Point To Point Protocol over ATM

These are different VC Encapsulations. They differ in some ways (the most important is that PPPoA allows for MTUs of 1500), but there is mostly no difference in speed between the two.

Here's a more in-depth discussion, although relative to BellSouth, but good info: /faq/1416


Short for Public Switched Telephone Network, which refers to the international telephone system based on copper wires carrying analog voice data. This is in contrast to newer telephone networks base on digital technologies, such as ISDN and FDDI.

Telephone service carried by the PSTN is often called plain old telephone service (POTS).

PVCs - Permanent Virtual Circuits ?

Permanent virtual circuits (PVC's) are permanently established connections that are used for frequent and consistent data transfers between DTE devices across the Frame Relay network. Communication across a PVC does not require the call setup and termination states that are used with SVCs. PVCs always operate in one of the following two operational states:

Data transferData is transmitted between the DTE devices over the virtual circuit.

IdleThe connection between DTE devices is active, but no data is transferred. Unlike SVC's (Switched Virtual Circuits), PVC's will not be terminated under any circumstances when in an idle state.

QoS ?

QoS stands for "Quality of Service" & is the idea that transmission rates, error rates, and other characteristics can be measured, improved, and, to some extent, guaranteed in advance.

QoS is of particular concern for the continuous transmission of high-bandwidth video and multimedia information.

Remote DSLAM?

A Remote DSLAM is an extension of the DSLAM in your CO (Central Office). It acts like an amplifier, in a sense. So, the same copper loop length restrictions apply to that Remote..(depending on the gauge of wire within the facilities)..the service envelope from that remote would be 18kft out (24 ga wire) or 15.5kft out (26 ga wire)

Repeater ?

In telecommunication networks, a repeater is a device that receives a signal on an electromagnetic or optical transmission medium, amplifies the signal, and then retransmits it along the next leg of the medium.

A series of repeaters make possible the extension of a signal over a distance. Repeaters are used to interconnect segments in a local area network (LAN).

RT (Remote Terminal)?

A Remote Terminal (RT) is fiber fed extension of the central office bringing the capabilities of the central office closer to customers. The remote terminals use next-generation digital loop carriers (Litespan, SLC, Urban, Optera) to provide high-speed data services and traditional telephone service to additional customers, typically those who live farther than a two or three-mile radius of a central office. Remote terminals take many forms including Cabinets, CEV's and Hut's. One example of widespread deployment of RTs is SBC's Project Pronto.

SMDS (Switched Multimegabit Data Service) ?

SMDS is a high-speed, packet-switched, datagram-based WAN networking technology used for communication over public data networks (PDNs). SMDS can use fiber or copper-based media.

It supports speeds of 1.544 Mbps over Digital Signal level 1 (DS-1) transmission facilities, or 44.736 Mbps over Digital Signal level 3 (DS-3) transmission facilities.

In addition, SMDS data units are large enough to encapsulate entire IEEE 802.3, IEEE 802.5, and Fiber Distributed Data Interface (FDDI) frames.


The vast majority (possibly all) DSL lines are rated at their sync rate. Since DSL runs over atm/frame relay, it is very important that your DSL modem or router and the DSLAM (the device that takes data from your modem and transmits it onto your ISP's network and vice versa) use a common frame size and frame rate. Your sync rate is only really affected by one thing: Packet loss. DSL companies in 99.9% of cases guarantee only the sync rate on residential lines. This is also why providers will never give you the maximum amount of speed you can theoretically receive. Since there are really no factors that affect sync rate on a regular basis they can do this.

The reason you never achieve your sync rate is because of latency and the internet. Once the signal is off of your local telco line, then it is affected by MANY MANY other things. There have been many good descriptions of how latency and the internet work. If you want more information, then check this out.


TLS (Transport Layer Security) ?

The TLS protocol provides communications privacy over the Internet. The protocol allows client/server applications to communicate in a way that is designed to prevent eavesdropping, tampering, or message forgery.

Training the line?

Training the line comes from the days of analog modem connections. Remember the long sequence of hisses, beeps, and just some other plain wierd sounds after the dialing of the modem?

Training the line means to negotiate the best possible speed on the line. Sometimes, line noise can interfere with normal DSL line traffic, so, the modem must negotiate the best possible speed despite the noise.

With the noise, the best speed can't be offered, so, it throttles the speed back through a negotiation sequence so that you can get the best speed and connection stablility despite the noise.

Trouble Ticket?

A trouble ticket is an official complaint to the Tech Support department because standard troubleshooting via the phone or e-mail has not corrected the problem.

The life of a trouble ticket:

Once the mainstream Tech Support representative has exhausted all the things they can do by just talking, they submit a "trouble ticket" to someone who has more resources to correct the problem.

Once a trouble ticket is inserted in the pool, it must wait for an engineer to open the complaint. Once the ticket is open, the engineer then diagnoses the problem, and then checks all the ISP's settings, hardware, etc. that could relate to the issue. Once something has been discovered or done, the engineer makes a note into the ticket.

The note in the ticket is a comment from the engineer that states what he has found and what could be done to solve the issue (if not solved already).
At this point, the ticket is closed. Usually the ISP contacts the customer stating the results of the trouble ticket and asks for confirmation that the problem has been corrected. If the issue has been resolved, it's archived into your account details. If it hasn't, either the ticket goes back into the pool to re-check or a tech is dispatched to your location to check the physical end of the customer's side. Once the tech reports after the session has been completed, the ticket is then closed and everyone is happy again.

Upstream Signal to Noise Ratio

This basically shows how much signal the HEAD END is getting compared to noise. The higher this number is, the better. As this number goes down, it means there is more and more noise in the line.

Usually this is caused by bad shielding, R59 cabling, or bad connectors/wall plates. It's not easy to determine the location of interference.

Upstream interference means that the head end is getting a lot of noise around the frequency that your cable modem broadcasts at (15 to 50Mhz). Troubleshoot this just like you would "fuzzy LOW channels".

VPN (Virtual Private Network) ?

A virtual private network (VPN) is a way to use a public telecommunication infrastructure, such as the Internet, to provide remote offices or individual users with secure access to their organization's network. A virtual private network can be contrasted with an expensive system of owned or leased lines that can only be used by one organization. The goal of a VPN is to provide the organization with the same capabilities, but at a much lower cost.

A VPN works by using the shared public infrastructure while maintaining privacy through security procedures and tunneling protocols such as the Layer Two Tunneling Protocol (L2TP). In effect, the protocols, by encrypting data at the sending end and decrypting it at the receiving end, send the data through a "tunnel" that cannot be "entered" by data that is not properly encrypted. An additional level of security involves encrypting not only the data, but also the originating and receiving network addresses.

A List of Broadband Terms

You can explore an extensive list of terms and definitions related to broadband HERE.


-Hz stand for Hertz. A measurement of frequency in cycles per second. One Hertz is one cycle per second.

-KHz stand for KiloHertz. It is equal to 1000Hz.

-MHz stand for MegaHertz. 1 MegaHertz is equal to 1 000 000 Hz or 1000 KHz.


One MBaud is equal to 1,000,000 symbols of information per second.


-Shielded cables has protected againt parasites and line interference. It is protected by a coating of aluminum, copper, or other materials.

-Unshielded cables have no protection against any parasite of interference.

vDSL & vhDSL

Very-high-bitrate DSL (VDSL or VHDSL)[1] is a DSL technology providing faster data transmission (up to 52 Mbit/s downstream and 16 Mbit/s upstream)[2] over a single flat untwisted or twisted pair of copper wires. These fast speeds mean that VDSL is capable of supporting high bandwidth applications such as HDTV, as well as telephone services (voice over IP) and general Internet access, over a single connection. VDSL is deployed over existing wiring used for POTS and lower-speed DSL connections. This standard was approved by ITU in November 2001.

Second-generation systems (VDSL2; ITU-T G.993.2 approved in February 2006) utilize bandwidth of up to 30 MHz to provide data rates exceeding 100 Mbit/s simultaneously in both the upstream and downstream directions. The maximum available bit rate is achieved at a range of about 300 meters; performance degrades as the loop attenuation increases.

Currently, the standard VDSL uses up to 7 different frequency bands, which enables customization of data rate between upstream and downstream depending on the service offering and spectrum regulations. First generation VDSL standard specified both quadrature amplitude modulation (QAM) and discrete multi-tone modulation (DMT). In 2006, ITU-T standardized VDSL in recommendation G.993.2 which specified only DMT modulation for VDSL2.

1.1 Equipment

Will my old PC be fast enough for DSL?

Yes. Although if you start to use the DSL line to view video on demand or other memory and processor hungry functions you may well decide your PC is too slow. PC makers are probably hoping that the revolution in bandwidth will fuel sales wave in the next generation PCs, but there are already so many interesting things to do on the web with even a slower PC, and the majority of sites can quite happily be seen and used by slower PCs.

How does DSL connect to my computer?

Some DSL installations require your PC have a network card. If you have to provide this yourself, you are looking for a 10/100mbps auto-sensing PCI network card for a PC. You are looking for something with a brand you are comfortable with, for instance 3com or Intel. Price range is currently from $20-$60. don't waste your money on cards with features such as wake-up packet and lan management, since you are buying for home use.
Several other connection options exist. Residential DSL is often provided with a combined DSL modem and card, that is added to your PC. This card is all you need. These cards are known as PCI DSL modems, and are designed for Intel PCs.
Another connection option is a USB DSL modem. These are newer and more likely to suffer from incompatibilities wth your PC or operating system, but they have the advantage of working on Macintosh, and possibly USB capable laptops as well.
For small business, you are likely to already have network cards, as you would almost certainly have an existing local area network.

My new computer has a DSL modem. Can I use that?

Recently, Dells, Compaqs and other PCs are being shipped with in-built DSL capability. This modem is likely to be a G.lite DMT modem. Unfortunately, existing DSL networks are in varying states of G.lite compatibility.. even large Telco ADSL networks may not support G.lite yet. Checking with your chosen DSL ISP should reveal whether or not your G.lite modem can be used. As of Q1 2000, the answer is most commonly, no.

Do I always need filter for my other phone line devices?

The answer is basically no ... Here is why.

The use of filters is something that doesn't require a tech to come out and do. This means that it saves the ISP or CLEC some money for the tech.

Some ISPs (or you can ask) will install a separate line(pair) that is only for the DSL line. This requires a whole jack to be used and no phones or other devices attached to that jack. In this situation, no filters are needed.

Also see this discussion on "home runs" by SplitPair in the Bellsouth forum.

How many filters do I need?

You need one for every phone jack you use (even for fax, and answering machines). Please be aware home alarm systems, or certain kinds of emergency assist phone hookups may complicate things and require you to use a splitter instead of microfilters.

Also keep in mind other terminal points, such as your cable/satellite TV decoder.

DSL modem and surge protection

DSL modems can be taken out by thunderstorms so you do need a surge protector if they are frequent in your area.
Unfortunately, surge protectors have also been reported to reduce download speed, so you would be advised to test your speed before and after installation to make sure that it adds no problems to your line.

What is the difference between a hub and a switch?

A hub shares all traffic to all nodes whether they are interested or not. The maximum traffic that a hub can handle is when the SUM of all traffic reaches close to the hub speed (usually 10mbit). In reality, a hub starts to become inefficient when constant traffic on many ports rises to a SUM of just 3mbit! This inefficiency shows up as high "collision rates" being recorded by the attached devices.

A switch knows where traffic is bound for, thus a switch is able to handle its advertised speed (10mbit or 100mbit) on EACH port that it has.

With a correctly configured switch, and full duplex connections, ethernet interfaces should not show "collisions" when attached to a switch.

Where Can I Get A DSL Line Surge Protector?

RadioShack has a surge protector (Model: 61-2146) specifically for DSL modems.

Do all surge protectors slow down your connection?

Not all of them. I have a tripplite isobar with network and cable protection that allows me download speeds of over 1500.
From another user: I use an APC Back-UPS Office with network/cable protection and cannot see a measurable difference between running through the protector and going directly to the NIC.

Can I set up a router with my USB DSL Modem

UPDATE: There is a router for the Alcatel USB modem - the Vigor 2200USB, sold in the US.

Find out more here.

Linksys has a USB router (BEFSRU31 - EtherFast Cable/DSL Router with USB and 3-Port 10/100 Switch) that only replaces you NIC card in your PC. You cannot hook your USB DSL modem into it.

Will I have to upgrade my DSL modem every 6 months?

No. Even if you upgrade your line speed, your CPE (customer premise equipment) does not have to change. Until the commercial availability of G.lite (a newer DSL standard, offering vendor inter-operability), though, moving from region to region, or from one provider to another, may require different equipment. Check here for equipment pictures.

What exactly is a RADIUS Server.

A RADIUS (Remote Authentication DIal Up Server) is used to verify your username and password. Most ISPs are using this type of Authentication Verification.

Should the Network Packets light always be on, on my Hybrid Modem?

Yes, the Network Packets light should always be on and semi-flickering. The Power and Lock lights should also remain on.

Will a Efficient Networks 5250 work with ADSL

No. The 5250 is a SDSL modem.

I have this Netopia router from Northpoint/ other CLEC, What can I do with It?

Netopia Routers are modular and contain 2 WAN slots, and They support many different Wan types, and can be field upgraded to other Wan Technologies, so you have an R7100-C (Copper Mountain Compatible SDSL), Meaning it has a SDSL card in Slot 1. Some ISPs provided customers with a R7120-C this router has a SDSL card in slot 1 and an Analog Modem in slot 2 (for Dial Backup). If you have a Netopia R series router you can purchase either from your ISP or a distrubitor like CDW, Ingram Micro, Tech Data or Microwarehouse different WAN cards (WANLETS) they are available for the following Technologies:
T-1 TER/53
SDSL (Nokia, Paradyne, Lucent Stinger , Nortel) TER/72
IDSL/ISDN (Copper, Nokia, Paradyne, Lucent, Switched ISDN) TER/31
ADSL (G.Lite/G.DMT) TER/61
Analog V.90 TER/20
Netopias can also have the same DSL technology in both slots and combine them in to a Single Pipe (Duoble bandwith) but the ISP and CLEC must support it.

How do I remotely restart (for resync) my dataquest modem?

Because I found better performance (speed) when my dataquest modem was located some distance from my computer, i.e. directly at the telephone entry point, I wanted a way of asking my modem to resync to a higher data rate periodically when I discovered it had ratcheted down to a lower rate due to loss of sync. This saved a long walk down the driveway in the rain.

Go to the built-in modem diagnostic web page, (» then click on "Help", then click on "advanced settings", then without changing anything click "save settings".

This forces a resync. One can watch the progress by going back to, the dsl diagnostics page and periodically asking for a reload.

It takes a bit of time for anything to happen, and you will see 0 bytes/sec for a time, then when it's all setup (at the hopefully higher rate), the new data rate will be displayed.

Some restraint is necessary here as the ratcheting down in speed is supposed to place you at an acceptable speed for your line condition, but I find that periodic restarts keep the speed up.

I found much improvement by placing my modem far from the computer and home generated noise. The ethernet connection is now 250 ft. long and seems to work flawlessly.

Can I switch a Cisco 678 modem from CAP to DMT?


If you download the DMT firmware upgrade and follow the instructions EXACTLY you will get a working Cisco 678 with DMT that was previously set at CAP.

As a Qwest customer, I got the firmware and followed their instructions here:
» ··· ups.html
using their downloads and hyperterminal.

Cisco has a guide here:
» ··· d1095542

Of course, the standard warnings apply that if you mess up the firmware upgrade you will be the proud owner of a new doorstop instead of a router.

Since at the central office a DSL connection using CAP uses different hardware than DMT uses, you will lose your DSL connection until your provider makes their hardware change at the Central Office. You will see your WAN link and activity lights go dark until this happens.

After flashing, you will also need to completely reconfigure your modem as the setup commands for DMT are different than for CAP. (e.g. for Qwest see » ··· 675.html )

1.12 Cat 5 Wiring

(UTP Cat 5 wiring): How far can I go with Cat 5 cable?

According to ANSI/TIA/EIA-568-A standard, "horizontal wiring" from a wiring closet to the outlet should be 90 meters or less, plus another 3 meters for a patch cord to the workstation. In round numbers, that's about 300 feet.

If you plan to connect between buildings with different power sources, or go beyond 300 feet, you should consider using fiberoptic line with a media converter at each end.
by DTVtech

(UTP Cat 5 Wiring): What's the difference between 568A and 568B?

TIA/EIA-568A and -568B are two standards for connecting Category 3 and Category 5 wire to connectors. Both are appropriate for high speed data, though 568B is somewhat more common for installed wiring and 568A is more common in jumpers. There is no performance advantage either way. The only real difference between the two is the order in which the pairs are used (orange and green).

Hold a cable as if to plug it into a wall jack, the locking tab down (contacts facing you). The contacts are numbered 1-8 from left to right. Here's what you will see:

Pin 1: White/Green
Pin 2: Green/White (or just plain Green)
Pin 3: White/Orange
Pin 4: Blue/White (or just plain Blue)
Pin 5: White/Blue
Pin 6: Orange/White (or just plain Orange)
Pin 7: White/Brown
Pin 8: Brown/White (or just plain Brown)

Pin 1: White/Orange
Pin 2: Orange/White (or just plain Orange)
Pin 3: White/Green
Pin 4: Blue/White (or just plain Blue)
Pin 5: White/Blue
Pin 6: Green/White (or just plain Green)
Pin 7: White/Brown
Pin 8: Brown/White (or just plain Brown)

568A and 568B may be used interchangeably in a system SO LONG AS both ends of a given cable are terminated the same way.
by DTVtech

(UTP Cat 5 wiring): Can I use a modular coupler to join two network cables?

There are some couplers out there designed for category 5 wiring, but most are not -- they're mostly intended for extending cellular and business phone sets. And it isn't always apparent which are which.

In general, you are better off using one cable of the right length than joining several together.
by DTVtech

(UTP Cat 5 wiring): What are those plastic clips that came with my RJ45 jacks?

They provide some strain relief (so the wire doesn't pop out of the connection) and keep dirt and moisture out. They are not a replacement for using a proper punchdown tool to make the wire connection.
by DTVtech

(UTP Cat-5 wiring): Why are the RJ45 plugs I crimped on failing?

There are two varieties of category 5 wire that should be used: one has solid conductors and is generally used for permanent wiring; the other has stranded conductors and is generally used for making flexible patch cords. Some RJ-45 plugs are designed for solid wire (their contacts straddle each conductor), others are designed for stranded wire (and pierce through between of the strands). Using the wrong type of plug for a given type of cable will make a poor connection that may fail intermittently. There is a third variety of RJ-45 plug that will work with either solid or stranded wire.

Another cause of bad crimp connections is using the wrong crimping tool for a given brand of connector. In particular, many AMP brand connectors have the strain reliefs located in a different position than most. Using a standard tool with these plugs will damage the plug.

Ensure that the wires when cut are of equal length and pushed all the way up into the plug so the copper is flush at the top.
Added by an anonymous member:
Solid CAT5 wire which is cheaper and used to span any appreciable distance must use IDC (Insulation Displacement Connectors) using a punchdown tool at the patch panel or jack. Solid wire is also much more efficient at transmitting data. Stranded CAT5 wire must use IPC (Insulation Peircing Connectors) and is used for the short distance from patch panel to network switch or device or computer, thus the term 'patch cable'. Therefore, solid wire IDC terminations should always result in an impact tool IDC connection in a CAT5 JACK. Stranded wire IPC terminations should always result in a compression IPC connection in a CAT5 PLUG. The length of untwisted pair may not exceed one half inch at the plug, and twist should be maintained all the way to connection point on the jack. Solid wire connections, once installed, should never be disturbed. Ensure that the outer jacket of the UTP cable is crimped within the RJ45 plug to provide strain relief.

by DTVtech and outkast7621

(UTP Cat 5 wiring): Why do some patch cables have boots?

They look nice, and the companies that make patch cables can sell them for more money. Also, when you pull a cable back through a nest of other wires the boot keeps the locking tab on the plug from getting snagged and broken off. (That probably isn't a big concern for most home networks!)

Do boots keep dust out? Possibly, but a jack with a plug in it shouldn't be getting stuff in there anyway... it's the empty jacks that collect lint.
by DTVtech

(UTP Cat-5 wiring): Is plenum cable any better than PVC?

Plenum rated cable is required by some fire codes if you run wiring in locations where the HVAC system moves air -- above suspended ceilings and through cold air returns, for instance. This cable is designed to withstand higher temperatures than ordinary PVC jacketing and burns less readily than PVC. For most homeowners, plenum rated cable is probably not necessary and typically costs 2-3 times more than PVC. There is no electrical difference between the two, and either will perform equally well.
by DTVtech

(UTP Cat-5 wiring): What's all this about twists?

Each network cable contains four pairs of wire, each pair twisted at a regular rate. Better grades of cable deliberately apply different amounts of twist to each pair. 10-Base-T and 100-Base-T lines use two pairs, one to transmit and one to receive data, copper Gigabit uses all four pairs. The twists provide a consistent impedance along the length of the cable, reduce the crosstalk between pairs and tend to make induced noise cancel out.

To preserve these qualities, it is important to maintain the twist when installing connectors, right up to the point of termination. You shouldn't untwist more than about a half an inch of wire. And when you install the cable, take care not to pull it tightly or make sharp bends, as those will disrupt the pairs' integrity.
by DTVtech

(UTP Cat 5 Wiring): What are 66 and 110 blocks?

Both are "punchdown" blocks used to interconnect voice and data systems in an orderly way. Type 66 blocks have been around longer and were developed for the phone company; they make it easy to connect multiple phone taps to a given line, and with the use of bridging clips provide an easy way to disconnect inside wiring from a circuit for troubleshooting. Older 66 blocks are not suitable for category 5 wiring, although several manufacturers have come out with revised 66 blocks that will work.

110 blocks are newer and are preferable for computer work: for one thing, they make it easier to preserve the twist in each pair right up to the point of connection. Most Category 5 jacks also use type 110 terminals for connecting to the wire.

A traditional impact punchdown tool with interchangeable bits like a Harris/Dracon will cost about $75 and can punch either 66 or 110 blocks (or any number of other types). Less expensive impact tools without interchangeable bits run about $25. Both kinds of impact tools both connect and trim the wire to the correct length. For a couple of bucks you can get a plastic tool for 110 blocks that might get you by for a few connections, but it won't trim the wire. Personally, I would stick with an impact tool.
by DTVtech

(UTP Cat 5 wiring): Isn't coaxial cable better?

Coax is always better than twisted pair. The 10base2 is a limited by the equipment on either end of the cable. The cable has a very high bandwidth capability, if the proper equipment is attached on either end. If you look at it from a very narrow data persons point of view, not an electronics person, 10base2 is slower than cat 5 cable. Cat 5 cable won't come close to RG-58.

By NickNielsen
Member Comment:

One should qualify what "better" means in this context. Cat 5 cables are "better" if light weight, low cost and flexibility are important. Cat 5 cables are "better" if one doesn't want to deal with TNC connector hardware and cable terminators. If achieving the highest speeds over longer distances is more important, then coaxial cable is "better"
From DSLR member fivebyfive See Profile

What is the difference between Cat-5 and Cat-5e?

Cat-5e is enhanced Cat-5 cable. The only difference between the two UTP cables is the tested signal level. Cat-5e is tested at a higher frequency or signal level than regular Cat-5. You could find Cat-5 and Cat-5e anywhere for about the same price. Getting Cat-5e means you are getting cable that is tested under higher standards.

What is a crossed or cross-over ethernet cable and how do i make one?

A crossed ethernet cable is used for communication between two computers without using network gear such as a router, switch or a hub.

To identify a cross-over ethernet cable, hold one end as if to plug it into a wall jack, the locking tab down (contacts facing you). The contacts are numbered 1-8 from left to right. One end will have a different color sequence to the other. A crossover cable, like a straight through cable, works both ways.

Using the 568B standard, the wiring sequence for ONE end (that may be labeled T-568B):

PIN 1 - White/orange
PIN 2 - orange
PIN 3 - white/green
PIN 4 - blue
PIN 5 - white/blue
PIN 6 - green
PIN 7 - white/brown
PIN 8 - brown

The for the OTHER end (that may be labeled T-568A):

PIN 1 - White/green
PIN 2 - green
PIN 3 - white/orange
PIN 4 - white/brown
PIN 5 - brown
PIN 6 - orange
PIN 7 - blue
PIN 8 - white/blue

If both ends have the same color sequence (usually T-568A, but it doesn't really matter), it is a straight-through cable.

1.2 Struggling to get DSL

My neighbor has DSL, why don't I?

DSL is a technology where distance really matters.

Most Telcos limit ADSL lines to 15,000 ft from the CO (not as the crow flies, but how long the actual circuit is). If you're lucky, it may be 18,000 ft.

If your neighbor across the street has DSL and the phone company will not qualify you, there are several possible reasons why.
• Your neighbor may have gotten lucky and he caught the loop before it went around the ENTIRE block.

• The Telco's records may be out of date.

• Your telephone service could be served out by a different CO than your neighbor's. (This is rare but it is possible, especially in metropolitan areas where the COs are overcrowded).
In any case, if your neighbor has DSL, odds are you'll get it soon.

If I am too far to get ADSL from one provider, is it the same for all?

Most ADSL providers will not go out to the maximum distance that the technology allows, which for practical purposes is a bit over 18,000 ft. For example, Bell Atlantic will only go up to 15,000 ft, whereas Pacific Bell will go to about 17,500 ft, but some of the CLECs will go to the full 18,000 ft for ADSL, and even further for some other forms. For more information about the distance different providers go out to, under About DSL, click on Distance on the left side of this site.

So just because one provider won't install it for you, you may be able to get it from another provider without any trouble.

You say I can get DSL, but my telco says no!

Your telephone exchange may have equipment from a CLEC for DSL, but not yet from your local Telco! In that case, you may get DSL through the CLEC (or partner ISPs). Telcos have no knowledge of what services are offered by companies locating equiment in their facilities.

If I change phone number would it help to get dsl?

In most cases, regions around a CO are connected to that CO and no others. In the majority of cases, even if you identify a nearer CO, there is simply no copper running from that CO to your house. Requesting a new number will therefore not change your exchange, and your availability results.

One of our members had a different experience though. "Actually if you order a new phone number it increases your chances. My first phone number has no copper yet my second phone line does so it is possible. A friend of mine actually got a new phone number and got DSL on that number."

Should I order DSL thru the provider's web site or via the phone?

Depends on the DSL provider, the primary advantage to ordering on their website is that there is a lower likely of an error in the data entry process for your order. With phone orders, you have the benefit being able to make extra requests to person taking the order, including services that may not be available using the online form.

Why can't my phoneline get ADSL?

There are a variety of reasons why:

1. Too far from an equipped Central Office. This roughly means greater than 4.5km on AWG26 wire, give or take a kilometer depending on line quality.

2. Phoneline is "loaded" with a loading coil added for voice quality. Loading coils filters out all high frequency signals, the very ones ADSL needs for transmitting.

3. Phoneline has AML. AML allows two phone numbers on one single wire pair. Unfortunately, it doesn't work with DSL, and most telcos will not remove AMLs even if you request it.

4. Line has an incompatible service. This can be:
- pay phone lines
- Hotel/Motel lines. However, Canadian hotel owners can get DSL connectivity with DataValet by .
- digital lines (FX/RX, Centrex, Microlink, Megalink, DEA, DNA, LDDS). Some DSL providers use analog technology.
- PBX trunks and phone extensions
- CLEC loops (i.e. Bell Canada can't legally put Bell DSL on a Telus loop and vice versa)

DSL Availability & Troubleshooting

The following information was compiled by DSLR users julez_atf and quanta

DSL Why can't I get it? FAQ

Substitute "your telco" for Bell Canada (ON/QC/NWT/YT), Telus (BC/AB), Aliant (Maritimes), MTS (MB) or SaskTel (SK).

So you've tried all your phone numbers, and none of them come up as available in the ISP's web tool. But why? It could be due to one (or more) of the following reasons.

1) Too far - over 4.5 to 5.5km away from DSLAM
Reason: This is the most likely reason. You need to be roughly within 4.5km away from a DSLAM/RSLAM to sync at 1Mbps. If you have coarser gauge wire, you may be able to be 5.5km away, give or take a few hundred metres.

Fix: None. Wait until DSL service is implemented in your area.

2) DSLAM is full
Reason: This is the second most likely reason. ADSL is very popular! There are only so many DSLAM line cards for so many customers per neighbourhood.

Fix: Keep checking every three months. People cancel, and equipment is upgraded all the time.

3) Brand-new phone number
Reason: It takes a few days for new phone numbers to appear into the DSL availability database.

Fix: The number will probably appear by itself in a couple weeks. If not or you're in a hurry, see #4.

4) Error in WTN database (aka "My next-door neighbour can get ADSL but I can't?!")
Reason: You can get ADSL, but the web tool says you can't. It happens. Errors are very rare, but with 4 million numbers constantly being connected, disconnected, or transferred, some numbers slip through the cracks.

Fix: Read this post to get this fixed over the phone. »/speak ··· ;4126691

5) CO not equipped
Reason: You are within 4.5/5.5km of your CO, but it doesn't have any DSLAMs. Most likely to happen in less urban areas.

Fix: None. Wait until DSL service is implemented in your area.

6) Loaded line (loading coil equipped)
Reason: A loading coil is a lowpass filter that boosts voice quality for certain phonelines. Unfortunately, it filters out the whole spectrum required for ADSL in the process. Most likely to happen in rural areas.

Fix: None. Wait until DSL service is implemented in your area.

7) AML (Added Main Line) equipped
Reason: An AML allows two phone signals to run on a single pair - you get two phonelines in one. Problem is, ADSL doesn't work on an AML'ed phoneline. So if you have multiple phonelines, you may have an AML'ed pair or two. Also, your neighbour may have an AML off your wire pair or vice versa if one of you have a faulty phoneline pair.

Fix: If it's because you have two phonelines, cancel one of the lines. If it's because you have three phonelines, try the phone number for the non-AMLed line. If not, there is little you can do, unless you know someone "in the inside". Your telco won't remove the AML, because that is a removal of service.

8) CLEC loop (local phone service from someone other than your local telco)
Reason: If you use local phone carrier from, say, Sprint, you can't get ADSL. Legal reasons regarding database sharing, I believe. Different long distance carrier is fine.

Fix: None, besides ditching your CLEC and buying phone service from your telco.

9) "Sympatico/Velocity website says Yes but Joe's DSL ISP says No"
Reason 1: Wholesale ISP does not support that area at this time.
Reason 2: You are using an unlisted number. For legal reasons, your telco cannot divulge it to anyone, including another ISP.

Fix: Not much can be done for #2. For #1, try another ISP. If all else fails, use the DSL service from your local telco.

10) Party lines
Reason: They are not compatible with ADSL technology. Most likely to happen in rural areas.

Fix: Remove party line.

11) Digital lines of any kind (ISDN - Microlink/Megalink, Centrex, PBX, DNA)
Reason: ADSL is analog between you and the DSLAM. They don't work on lines running ISDN, a PBX, etc. This will happen in office buildings, hotels or convention centres.

Fix #1: Order a standard analog phoneline for ADSL, or try checking for ADSL availability on your office's fax line. That will be an analog line for sure. (Obviously if you have a business phoneline, you will have to go with business-class ADSL)
Fix #2: A company called TravelNet » has a product called DataValet that will allow your hotel/motel to receive Bell Canada ADSL.

12) Public payphone, cellular phone number
Reason: Self-explanatory.

Fix: None.

13) Incompatible equipment on line
Reason: You have had service with an ISP on Nortel equipment in the past and that provider never submitted a removal request for the DBIC card.

Fix: Contact your old ISP and ask for the card to be removed so that your new ISP can request that your line be connected to a DSLAM

DSL Troubleshooting FAQ

No Sync

This is *not* an ISP issue.

Possible causes:

1) filter connected to modem

- remove filter from modem

2) modem not connected to phone jack

- connect modem to correct phone jack

3) telephone(s) not filtered

- filter telephone(s) or disconnect them

4) defective modem

- replace modem
- contact ISP if modem was provided with service

5) incorrect VPI/VCI settings

- configure correct VPI/VCI (0/35 Eastern Canada, 0/32 Western Canada)

6) faulty linecard / dslam port at CO

- contact ISP and they will have Bell Nexxia investigate

7) non-payment of telephone service

- contact CLEC

8) modem connected to wrong line (multi line household)

- connect modem to correct phone line

9) modem not installed properly (internal modems only)

- check with vendor for installation instructions
- contact ISP if modem was provided with service

10) service cancellation

- contact ISP

11) service not available with CLEC (other than Bell)

- contact CLEC to verify they support DSL

12) distance from CO exceeds maximum guaranteed distance

- contact ISP and they will have Bell Nexxia investigate

13) outside line issue (loaded coils, bridged taps, wear & tear)

- contact ISP and they will have Bell Nexxia investigate

14) defective filter(s)

- replace filter(s)
- contact ISP if filter(s) were supplied with service

15) faulty inside wiring / phone jack(s)

- call 611 (note, this is at your own expense)
- repair your inside wiring

Intermittent Sync

This is *not* an ISP issue.

Possible causes:

1) telephone(s) not filtered

- filter telephone(s) or disconnect them

2) defective modem

- replace modem
- contact ISP if modem was provided with service

3) faulty linecard / dslam port at CO

- contact ISP and they will have Bell Nexxia investigate

4) distance from CO exceeds maximum guaranteed distance

- contact ISP and they will have Bell Nexxia investigate

5) outside line issue (loaded coils, bridged taps, wear & tear)

- contact ISP and they will have Bell Nexxia investigate

6) defective filter(s)

- replace filter(s)
- contact ISP if filter(s) were provided with service

7) faulty inside wiring / phone jack(s)

- call 611 (note, this is at your own expense)
- repair your inside wiring

8) interference from AM radio

- place modem away from AM radio
- use shielded twisted pair cabling from modem to walljack

9) interference from halogen lights

- place modem away from halogen lights
- use shielded twisted pair cabling from modem to walljack

10) modem overheating

- turn modem on its side
- keep other objects away from modem
- contact ISP (if modem was provided) or vendor if overheating persists

Slow Speed / Low Sync

Possible causes:

1) telephone(s) not filtered

- filter telephone(s) or disconnect them

2) faulty linecard / dslam port at CO

- contact your ISP and they will have Bell Nexxia investigate

3) distance from CO exceeds maximum guaranteed distance

- contact your ISP and they will have Bell Nexxia investigate

4) outside line issue (loaded coils, bridged taps, wear & tear)

- contact your ISP and they will have Bell Nexxia investigate

5) defective filter(s)

- replace defective filter(s)
- contact ISP if filter(s) were provided with service

6) faulty inside wiring / phone jack(s)

- call 611 (note, this is at your own expense)
- repair your inside wiring

7) interference from AM radio

- place modem away from AM radio
- use shielded twisted pair cabling from modem to walljack

8) interference from halogen lights

- place modem away from halogen lights
- use shielded twisted pair cabling from modem to walljack

9) congestion on route to destination

-check to see if anyone else with your ISP has started a thread about congestion
-run a traceroute to and post your results along with speedtest and tweak test results

10) incorrect MTU / RWIN settings

- the correct MTU for PPPoE is 1492 (unless otherwise indicated by your ISP)
- for help with RWIN check »/tweaks
- for more assistance post the results of your tweaktest along with information about the type of connection you have

A few more things to consider as interference in "Slow Speed / Low Sync"

11) interference from poorly shielded speakers
- place modem away from speakers or purchase new ones

12) interference from poorly shielded computer power supplies (PSUs)
- place modem away from PSU or purchase new one for PC

13) using cheap "dollar store" RJ-11 phone wire between phonejack and modem
- use standard "flat wire" RJ-11 wire included with modem, or, if missing, purchase high quality phone cable. Do not use phone extension cable if you can.

14) overclocked the FSB, causing problems with PCI network card
- if you are overclocking the front-side bus multiplier, return it to the default multiplier. Or try experimenting with another brand of network card.

15) setting PCI latency = 64 in BIOS causing problems with PCI network card
- go to BIOS and set PCI Latency back to default of 32. Or try experimenting with another brand of network card.

16) more than 5 devices connected to phone line

17) Excessive loop length/distance from the DSLAM

- disconnect enough devices so that you are at a maximum of 5 devices (including answering machines, modems, etc.)
This will also cause intermittent connectivity and no synch.

Why can't I get DSL even if I'm only one foot from my CO?

If you have a bridge tap, it will make it hard for you to get DSL access unless your ISP runs a new line over to your place. If you have a load coil installed, it surpresses the high-frequency used for DSL. It may make phone conversations sound clearer, but it'll make DSL sound a LOT WORSE.

1.3 Line Sharing FAQ

What is Line Sharing?

Line Sharing refers to a ruling last year by the FCC that paved the way for competition for data services over your existing phone line.
This means that you are able to choose data (DSL) service from other companies apart from your local Telco, but avoid the installation of a second phone line at your premise.
Line sharing is regarded as critical for the success of an open DSL market.

Filters and line-sharing

A distributed filter, or micro-filter, is a small electronic component that fits between your phone line and a regular voice device, such as a phone, a fax, or any device with a regular modem such as a cable box, alarm system or digital TV.

When DSL (ADSL) is provided over voice lines, all devices in the house except the DSL modem must be connected through filters. The filter protects the phone devices from high frequency noise. They are low-pass filters. The filter is also there to protect the DSL signal from being contaminated by high frequency noise added by analog phone devices, answering machines, etc.

During a Line Sharing install, one important question is how many devices require filtering, as this determines how many filters are supplied with the install kits.

Do I need cable service to get Cable Internet?

No, you don't. The cable installers will come out and install a hard line right into your home. Beware though, when you do this your monthly payment will normally be higher than if you do have cable TV service.

Sharing one-way cable with Linksys routers

For a LINKSYS Router:
  • In your browser, go to[] and login.

  • Go to the Status page, and write down the DNS numbers & the MAC Clone under the wan (Looks like:XX-XX-XX-XX-XX-XX)

  • Go to the Advanced tab and then Mac Clone, and type in the #, click Apply. Exit IE.

  • Go to Network Properties. You should have TCP/IP, and whatever else if you're networking. Click on TCP/IP.

  • Specify the IP as 192.168.1.[1-10]; a different IP for each machine.

  • Specify Sub Net

  • Go to Gateway -> type in

  • Go to DNS -> Enable
    -Host: Computer1
    -Domain: the name after your email [ie]

  • Now type in those DNS #'s you wrote down. If there are three, all three are good, but the first two are needed.

    If you need additional help, post in the LinkSys forum here on the site.

    For OTHER Routers:
    Do the same as above, on your router's home page.

Why is a line sharing install easier?

There is (normally) no requirement for any inside wiring.. the DSL service comes over your existing phone signals. Your local Telco does not have to visit your house, saving at least one install visit and one home-sit for you.
At present, Line sharing may still involve one visit from your CLEC to do the installation of the filters and the configuration of your DSL modem and verification of sync to the CO. In future, Line sharing is also expected to allow self installation for those who are willing to follow some technical directions.

Which CLECs support Line Sharing now?

Covad, Rhythms and NorthPoint all currently offer Line sharing. Exact availability varies from CLEC and from market to market.
In some cases (Rhythms, NorthPoint), the customer is currently able to specify they wish a Line sharing install. In other cases (Covad), Line sharing is the default if available and if the product chosen is ADSL.
SDSL and IDSL requests are technically unable to share a line with voice, so will still be done as another line install.

Does Line Sharing improve distance limits?

No. At least in the case of Covad, a distance estimate beyond 12000 feet, or a line that measures at beyond 15000 feet is rejected when ordering DSL.
If a line is not of suitable quality, Covad will currently refuse to consider using any other lines (for example secondary phone numbers), as in 85% of cases the 2nd lines also fail the quality tests.

What is a Splitter?

A splitter is the alternative setup for DSL and Voice in the same premise .. it sits at the NID, or entry point of the line to the premise, and splits off the data portion of the signal so that it can be run cleanly through the house.
Generally, splitters support full rate ADSL if available, whereas filters limit top speed to a megabit or so.

What is a Y-Adapter

Where a socket needs to provide both voice and DSL, a Y-Adapter can be used. Exactly as it sounds, this simply splits the socket into two, so that one can have a filter and a phone attached, and the other goes to the DSL modem.

What Covad products support line sharing?

TeleSurfer ADSl and TeleSurfer Pro ADSL only.

How is the install delay on linesharing installs?

The expectation is that the install window will drop from 30-45 days currently to about 10 business days. You only need to be home for one visit: the one from the CLEC install technician.

Why would I get a splitter rather than filters?

A Splitter would be instaled for end-users that have a home alarm system wired into the phone lines, or have a Telecommunication Device for the Deaf (TDD) installed. The filter install is the default.

How is a Line Sharing order placed?

Since the data service is added to your existing phone line, it is critical that you correctly identify
• the primary PHONE NUMBER at your premise
• the exact list of phone related devices currently connected.
• whether you have a home alarm system, TDD, or wall mounted phones
• Whether you have caller ID or any premium telco services activated
• The address of the premise as it appears on your telco phone bill
• The name of the person or company as it appears on your telco phone bill
If any of this information is missing or incorrect, the order can be delayed or even cancelled.

My phone line is not billed by my ILEC!

In the case where your voice line is not provided by your local telco.. for example, you are in verizon territory but have local phone service through RCN, or through Sprint.. although the ILEC controls the physical line, the first layer of voice support is of course the company you ordered local service through.
In these situations, Line Sharing may not be available to you, since currently the CLEC (for example, Covad) is required to have inked agreements for your area with not just the big Telco, but all the competitive voice providers as well!
As of the time of writing (Q1 2001), the FCC and some state regulatory authorities are pushing the "baby bells" to upgrade their systems so that customers that have elected to use other voice companies for local phone service are not precluded from getting DSL. It is expected that this real block to getting DSL will be removed completely by the end of the year.

What troubleshooting can I expect during an install?

During install, if sync cannot be obtained at the DSL jack, after filters are installed, the technician will try to obtain sync further backwards in the wiring, all the way to the NID if necessary. This will eliminate or identify house wiring problems that cause sync problems.
If sync cannot be obtained at the NID, the Technician will call in to run a test to see if sync "noise" reaches the DSLAM at your CO or not. No noise at the DSLAM means a problem at the CO, most likely, your line has not been cross-connected to the CLEC DSLAM properly.
If noise is heard at the DSLAM, but sync is not obtained, then the technician may report the install is technically not feasible, which means your order is cancelled. If the technician has CO access they may be able to further troubleshoot CO wiring issues, improving the speed at which the ILEC can resolve the problem.

If sync cannot be obtained at the jack, then the technician may install a NID splitter, and run a new wire for the data.. this removes the need for microfilters.

If sync is lost intermittently at the jack, then the technician may test at the NID to see if sync is stable there. If it is, a splitter may be installed to avoid the internal wiring problems of the house.

Sync problems at the NID may require further work at the CO to isolate the problem to the loop (the line), in which case, the install is cancelled with a technically not feasible.

Must the ILEC fix line problems?

Currently the ILEC is not obliged to condition voice lines in case they are of insufficient quality (load coils, bridge taps, moisture in the line, cross talk etc), to support CLEC ADSL.
This means that the loop (line) success rate of line sharing installs may actually be lower than dedicated line installs.
In the former case, you, the customer, are stuck with the quality of the copper you already have to the CO. It is unlikely the CLEC can convince the ILEC to improve that line.
In the latter case (non line-sharing installs), the line is required to be of data quality to start with, thus the CLEC can request the ILEC fix many problems in order to get you installed.

What to do after Technically Not Feasible

Your ISP should try to help you, but the reality is that there is little that can be done to complete your original order.
You may be able to choose an SDSL product that requires a new (clean) line to be installed, as a replacement for your ADSL line-sharing request. Normally the price for these products will not be as competitive.
It is possible that ILEC ADSL will still be available to you even if your CLEC and ISP was unable to get you line-sharing ADSL. The ILEC may be more motivated to fix line problems found during installation of their own DSL product.

Is Line Sharing a win?

Line Sharing has been legally possible since the beginning of 2000. But, the requirement that CLECs must arrange complex access, pricing and troubleshooting agreements with every single Telco in their footprint means that there are signifcant barriers to entry of this market.
Only the largest CLECs (Covad, NorthPoint and Rhythms) have made some progress with line sharing in some markets meaning that for most consumers, nearly a year after the FCC inked the rules, there is still no ADSL choice beyond the local Telco.

Even for areas that are line sharing enabled, the CLECs have not yet put together with their ISPs self-install kits.. so a CLEC line-sharing order may still involve more visits (1) than a telco self-install order (0).

Finally, line-sharing makes the CLEC DSL products look remarkably similar to the Telco products, but not only are they are priced higher, but involve the home visit. In addition, we can safely predict a higher percentage of install failures may be encountered vs the Telcos own ADSL product.

Our view is it will be difficult for ISPs to sell the hidden advantages of line-sharing CLEC DSL products (reliability and quality of service) in the face of these visible disadvantages.

Finally, the increasing ties between SBC and Covad and Verizon and NorthPoint means that two out of the big three DSL providers will really lack the incentive to push products that squarely compete with the ADSL equivalent offerings from the Telco.

My CO is not up for Covad Line Sharing yet!

As at the time of writing, Q4 2000, it is predicted that by December 1st, you will not be able to place an order for Covad ADSL services at all.
You must wait to be notified by the ISP that the CO is enabled for line sharing.. Covad are not installing ADSL as second line installs.

Will the POTS service still function during a power failure with ADSL?

A qualified "yes".

IF the phone line is good from your home to the Central Office, and IF there is power to the Central Office, you will have phone service, much like you have phone service during many power outages. If, however, a line is down, or if there is no power to the Central Office and/or the Remote Service Unit (most have generators and/or battery backup), then you may well have no telephone service. The loss of "utility provided" electricity does not necessarily mean you won't have telco service, but it's not guaranteed, either.

The ADSL service is much the same. If the ISP has power, and if the Central Office has power, and if the lines are good, and if your notebook is charged, or if your home network is on a major UPS or filtered generator, you might have both POTS and ADSL service.

Will DSL give me a noisy phone line?

Answer: No if installed properly With line sharing technology the voice and dsl share the same copper pair. The reason they can do this is because they are in two different frequency ranges that aren't close enough together to cause a noisy phone line. When a splitter is installed at your house or when you use micro filters, the signals are separated to the appropriate device i.e. phone or dsl modem.

If your Isp uses line sharing, Important note!.

Important note: Up to 40% Of ISP's as of Feb. 2003 used line sharing to get provide you with DSL service (Michael Powell fcc, feb 2003 testimony house energy and commerce commitee).

Line sharing is the process of the CLEC as mentioned in the FAQ providing DSL services through a single phone line. The line sharing rule insured that the CLEC has access to the dominant ILEC line (such as sbc,qwest,verizon,bellsouth) to provide DSL while allowing you to continue to use them on the same phone line. However as a result of a February 2003 decision regulations will be eliminated in 3 years. If the ILEC doesn't want to give access to the lines or charge the price that CLEC's are willing to pay then your internet access may suffer if the CLEC loses access to the line. One example is Covad, however ISP's such as
Speakeasy use Covad instead of the ILEC sometimes. The solution is to check with your ISP as to what telephone provider the use to access your lines on the local loop. Then ask questions to the company on their access to the local loop via a contract or agreement. Changing ISP's in about 2 years(article written july 2004) maybe unburdensome to some but if you have a business if could mean changing email addresses and restructuring(changing router settings and individual pc settings).
If you plan on keeping the same isp for years, be sure to get information. There are many CLEC's out there and independent isp's who may use the CLEC for access.

2. DSL 201

ADSL, SDSL, VDSL, IDSL, help! too many acronyms!

Right now, your choice is probably going to be either SDSL or ADSL. ADSL is generally available more cheaply than SDSL, and usually from your local Telco, although Covad sells a lot of ADSL lines. ADSL is designed for the home user. (RADSL is a slight variation on ADSL, which supposedly offers a longer reach).

If you are going to be operating servers I would suggest SDSL if you can get it, not only because the maximum upstream speed is generally faster than ADSL, but because your DSL provider is more likely to understand your needs, give you a fixed ip and be more responsive to technical problems.

VDSL is a DSL technology like ADSL, SHDSL etc. and is used on copper wires, although fiber is usually used to connect the VDSL DSLAM to the world. It runs to 56mbits and will support 4 TVs (loads of channels), phone integrated to the TV (caller ID on the TV screen) and 1meg up and down for PCs.

What's the difference between bridged, dynamic or static IP and which is better?

Bridged refers to a method of getting data from your computer's ethernet card, through other hardware possibly, and to your ISP. This has already been discussed, and doesn't deal with IP addressing.

The difference between dynamic and static IP addressing is that, with a static address, your computer gets an IP number (the Internet equivalent of a telephone number) that is all its own for as long as you are a customer of that provider. Dynamic addresses can change (more often than not they don't, but this isn't guaranteed either), usually through a technology called DHCP.

Another wrinkle in all this is that some ISPs provide IP addresses that don't change, yet they are still dynamically assigned via DHCP. People often confuse these "fixed dynamic" IP addresses with static IP addresses.

Dynamic addressing has the drawback that if you're trying to run any kind of server (web, mail, gaming, etc) your computer will be more difficult to find as the people connecting will need your current address to connect. There are services such as DynDNS and DHS (free) that facilitate giving your dynamic address a name that everyone can consistently use.

There's no difference in speed or, usually, service between static and dynamic addressing, as its simply a method of giving your computer a destination address on the Internet.

What's the difference between ADSL and SDSL

ADSL is a DSL line that is mostly for low use. It has download speeds many times faster than its upload speeds. This is usually for simple tasks such as downloading and viewing webpages.

SDSL has upload speeds almost the same as its download speeds. This makes it optimal for gaming and servers of any type. Because the upload speed is high it is more expensive than ADSL.

For most uses ADSL is the best choice.

What is the difference between ADSL and IDSL?

ADSL is a service that runs at a different speed up and down, up to 8 megabits/sec down and 1 megabit/sec up, and is limited to distances of around 18,000 ft towards the high end, and cannot run through various devices that can be placed on the phone line such as a DLC (fiber in the line). IDSL is a service that is based on ISDN technology, runs at a maximum speed of 144 kilobits/sec each way, but can go anywhere ISDN can, at a distance of up to 50,000 ft with the currently used versions, and can run through most DLC.

What is the difference in RADSL vs ADSL?

RADSL is rate adaptive DSL, this means speed dynamically varies according to line conditions. Given an equal choice, choose ADSL or SDSL over RADSL, however in many cases, RADSL maybe the only choice available at the price, or at any price.
RADSL typically can reach further than higher speed ADSL lines due to its nature of throttling down when line quality is variable.

Why is an IDSL connection more expensive than a 1.5M/384K connection?

IDSL can be thought of as modern ISDN. The technology for IDSL is different than DSL, and since it is not as mass-market, it is also more expensive. Your money is not paying for bandwidth, it is paying for equipment and installation that is not as frequently performed, and therefore costs more.

To some extent, also, IDSL prices maybe higher because they can be: IDSL is often the only choice if you are sufficiently far away from your CO.

Where can I find an ADSL tutorial?

The University of New Hampshire has an interesting tutorial on the technical aspects of DSL here:

Slower SDSL or faster ADSL for Gamers?

If gaming is absolutely most important use of the line for you go for the slower SDSL connection because it can give considerably lower pings than ADSL.

If a mix of gaming and download and general usage is more important, you may be happier with ADSL because you can still get low pings, and you can get the faster downloads.

How do I choose an ISP with local facilities so I have low pings?

You need to verify with the ISP sales person that they have a LOCAL POP for you, or ask other users in your area on that ISP whether they are happy with the routing. Gamers normally know the most about how an ISP performs in this area.

If they cannot answer this question clearly and immediately, do not choose them for your DSL service.

How do I figure out how much bandwidth I need?

You can never have enough! The same advice people give for PC processor speed can be given for bandwidth: buy as much as you can reasonably afford, since nobody ever has "too much" bandwidth.

One of the main deciders though, is price ... for some reason, SDSL lines are considerably more expensive than ADSL lines, so unless you have a specific need for upload capacity, concentrate on the best value for money in ADSL services, then pay more for more speed if you can afford it.

If you insist on some rules of thumb: a small office can be reasonably happy with even a 144k IDSL line, if they are just "using the net" as a reference tool ... more than two people are unlikely to be dragging down web pages at the same instant.
On the other hand, a single user who is addicted to mp3s or large game demos, or who swaps video streams, would fill a connection ten times that IDSL capacity.

How do I reconfigure my laptop between home to Office

Unlike Mac, which has TCP Configurations ability, Windows does not provide any way to switch between networking configurations, as one might want to do with transporting a laptop between home (DSL) and office (ethernet) environments. The easiest thing to do is to try a shareware IP net switch utility.
Try one of
•Globesoft Multi-Net Manager,

If you are still stuck, try this resource
Switching network settings on a laptop computer.

Does an installer need to come out to my house if I have a shared line order?

NO! You don't have to worry with anyone cutting wires (oops) or installing a new line, so your order will be faster than typical dedicated line orders.
Line sharing installs will still require you to carefully follow installation instructions (connecting your PC, putting micro-filters on your other phone sockets and so on), so you may still wish a DSL installer visit, if that option is available to you.

Why is a 1.5mbs DSL line $100 when 2mbs cable is only $40

Your DSL line is a guaranteed 1.5mbs. Where as cable is a 10mbs shared line between people located on your node with no guarantee of speed.

[Update] You may also be looking at the offerings for a business quality DSL line. At this time (Oct 2005) DSL prices have dropped to make DSL more competitive with Cable.

What does a load coil look like?

A lot of people cant get DSL because of a load coil on their line...well here is your trouble:

(taken from here)

Thanks to the members of the Broadband photo forum for these images

What is TTL or Time To Live?

Q: Could someone explain the whole "time to live" thing with pings?
TTL or Time to Live refers to how many routers your packet can go through before it expires. Usually a packet finds its home in less than 32 hops, but 64-128 is a good default.
Q: Then why is the TTL 64 when I ping my host computer but 49 when I ping some other site?
Every time a packet passes through a router the TTL number is one less than before. If this counter didn't exist the internet as we know it could be at 100% bandwidth bouncing these packets back and forth that would never find a home if the destination is unreachable. That would make the internet unusable.

Every computer has its own setting for its packets when it comes to TTL. All that matters is the setting is high enough to allow the packet to reach its destination.
Thanks to BlitzenZeus for these answers.

What is the RWIN setting?

The RWIN is the TCP Receive Window. TCP is a packet based transfer where data packets are moved in chunks rather than one at a time. The RWIN itself is a "buffer" that gathers the incoming data until it is full, then it moves the data to storage before refilling. Between fills, the computer sends acknowledgement packets "acks" that tell the sending computer that the data was correctly received. Increasing the RWIN means that more data is gathered on each transfer, followed by a blitz of acks, followed by more incoming data, and so on. Smaller RWIN sizes gather less data per fill, and thus send fewer acks, and then the cycle begins anew. The trick is in finding the proper RWIN for your line speed and latency.

The TCP Receive Window has a default value of only about 8K bytes in Windows 95/98/NT, and about 16K bytes in Windows Me/2000/XP, which is adequate for relatively slow dialup modems and for high-speed networks with relatively low latency (e.g., less than 20 milliseconds). Increasing the TCP Receive Window above the default settings (e.g., to 32-64K) can substantially improve throughput on high-speed Cable Modem or DSL connections where there is higher latency (e.g., 100-200 milliseconds), as is often the case on the Internet, particularly over long network paths. (Increasing the TCP Receive Window will usually not have an adverse effect on other connections.)

For example, let's consider the case of downloading a file at 150 kilobytes per second from a remote server over a typical 1.5Mbps broadband connection. A default TCP Receive Window of 8K bytes will be filled in only about 53 milliseconds, which is often shorter than the round-trip latency on the Internet. When the window is full, the sender has to stop sending until an acknowledgment of the data that was received comes back from the recipient. With a TCP Receive Window of 32K bytes, the sender can continue for as long as 217 milliseconds without an acknowledgment, which should permit uninterrupted data flow even when latency is 100-200 milliseconds or more. (With a TCP Receive Window of 64K bytes, the sender can continue for as long as 450 milliseconds.)

The moral of the story is this: Slower download speeds on lower latency need a smaller (say, 10K) RWIN. High speed connections on long latency networks may need a much larger RWIN (say, 32000). Here below are some suggested settings to try for broadband connections, based on latency and rated download speed.

Low latency (<40ms)
500 Kbps --- RWIN 5000
1000 Kbps -- RWIN 10000
1500 Kbps -- RWIN 15000
2000 Kbps -- RWIN 20000
2500 Kbps -- RWIN 25000

Medium latency (<90ms)
500 Kbps --- RWIN 10000
1000 Kbps -- RWIN 15000
1500 Kbps -- RWIN 20000
2000 Kbps -- RWIN 25000
2500 Kbps -- RWIN 30000

Long latency (<150ms)
500 Kbps --- RWIN 15000
1000 Kbps -- RWIN 20000
1500 Kbps -- RWIN 25000
2000 Kbps -- RWIN 30000
2500 Kbps -- RWIN 35000

Adjusting your RWIN will not affect your rated line speed, it only allows for transfers to be of maximum efficiency. Some users should note that even if they signed up for 1.5Mbps max service they may be capped at lowers speeds such as 768Kbps or 384Kbps, depending on individual line conditions. Your RWIN has no effect (well, a negligible effect, anyway) on your TTL, MTU or latency! A well tuned RWIN can, however, greatly improve transfer speeds by increasing data transfer efficiency.

What is the MTU?

The MTU is the "Maximum Transmission Unit" used by the TCP protocol. TCP stands for Transmission Control Prototcol. The MTU determines the size of packets used by TCP for each transmission of data. Too large of an MTU size may mean retransmissions if the packet encounters a router along its route that can't handle that large a packet. Too small of an MTU size means relatively more overhead and more acknowledgements that have to be sent and handled. The MTU is rated in "octets" or groups of 8 bits. The so-called "official" internet standard MTU is 576, but the standard rating for ethernet is an MTU of 1500. When trying to decide what MTU is appropriate for your line, you must consider the type of connection you are using. For the purpose of this FAQ, we are going to consider only common cable and DSL MTU settings. Most cable and some DSL ISPs allow a standard 1500 octet MTU. In general, a 1500 MTU is what you would like to have since it works harmoniously with ethernet, but not all ISPs support an MTU of 1500.

Logically, you would also like to get as much data on each transfer as they are willing to send, so you would want select an MTU of 1500 (if your ISP supports it). This would ensure the best possible transfers. If you are using router PPPoE, then your max MTU as allowed by your ISPs and the PPPoE protocol is 1492. Other versions of PPPoE have maximum MTUs of 1400-1492(1438 max for AOL Plus, but 1400 is a better setting for AOL.) You may need to check with your ISP to find out what the maximum MTU is for your network. Setting an MTU that is too small or too great can have extremely deleterious effects on your broadband preformance. Altering your MTU will not affect your latency or TTL. Adjusting the MTU to its ideal setting creates more efficient transfers and thus better overall performance. A well-tweaked system can have high speed, fewer errors and better transfer efficiency.

3. Contracts

What does FAP mean?

Fair Access Policy - a limit on the amount of bandwidth you can use within a certain amount of time.

Why does my ISP prefer me to sign a contract?

ISPs usually must commit to a certain quantity of lines from the big DSL networks. Contracts make this more likely to be achieved. Contracts are preferred because of the investment in infrastructure the DSL providers and ISPs have made. They don't expect to make much money from you initially, especially as a new user usually needs expensive installation time, and often gets discounts on the equipment. This is similar to the beginnings of the cellular phone market, where the equipment was tied to a cellular provider, and sold at a discount, in return for a minimum service term. As DSL becomes more common, these contract lengths will probably be reduced or eliminated. No contract service is certainly available, just ask for it. It may cost more or you may have to pay for installation though.
ISPs also keep an eye on the capital value of you as a customer. People on contracts are more valuable to them in the case of a future sale or ISP takeover, than people on month-by-month. The value of you as a 2 year DSL customer now, in a takeover deal, can be over $1000 !

What do I look for in a contract?

Terms and conditions need to be read carefully. Understand that most special offers require you to sign up for 1 or 2 years! So in particular, you should watch for any clauses that allow the provider or ISP to charge you for early termination, or for moving from one location to another. In addition, the contract may specify what is not allowed, and this list, apart from the usual things like "no spam" and so on, may include more widely applicable terms, for instance, they reserve the right to terminate your line and charge you disconnection costs if you do anything they believe is "destabilizing" to the system. Without a clear definition of what "destabilizing" is, they are basically free to terminate your line anytime they want, and you have no right to argue about it.
Not really a subject for terms & conditions, but, also check what optional service costs are, like additional IP addresses and DNS service etc.
Also be careful to check for any traffic restrictions both up and down, or limits on supported configurations, or running servers at home. On the plus side, you should hope to see guarantees from them on committed information rates. And what your rights are when minimum service levels are not met.
If you like what the sales people say, make sure you get it in writing, and ask if they apply for the duration of the contract, because terms and conditions have a habit of changing after you signed up.

So here is a final checklist:

    what are any system requirements the DSL provider/ISP expect?

    Is rental an option for the CPE (premise equipment)

    Does the ISP offer any phone number for dial-up access backups? what about roaming

    How long does it take for service to be activated?

    What promised speeds are there, what happens generally at peak periods?

    Is there any recourse if promised rates are not met?

    Are all charges included in the quoted monthly fee?

    Are there are any data-transfer limits on download or upload side?

    Does the installer care about the PC or Operating system you have

    Will additional interior or exterior wiring be necessary?

    Who pays for any installation expenses?

    Do accounts come with any home directory, ftp or web space?

    What's the limit on e-mail addresses provided?


    Does the ISP monitor the state of the line for you?

    Is there a 24hour number for network operations center?

    Is routed IP available, and at what extra cost?

    Is this a PPPoE setup, are their plans to switch to PPPoE?

    What will the routing be from you to local internet sites?

    Will you be allowed to host a Web site?

    Does the ISP support reverse DNS lookups?

    What's the limit on IP address provided?

    What's the cost of extra IP addresses?

    If you have a home network, can you share the connection over it?

    If shared access is allowed, is any hardware or software support provided for it?

Will I have to pay a lot if I move houses?

If you plan to move, you should certainly ask exactly what the costs are of early termination of your current contract, prior to 12 months, and after 12 months, and whether you can take your equipment with you (if it is rented) to the new location, assuming it is serviced by the same DSL provider, and whether there are any discounts over a new install price given for such a situation. Also how much notice you have to give them.

Can I switch ISPs anytime? is there a penalty?

ISP switches are usually easy. You arrange this with the ISP, checking first if there are any penalties, then you locate another ISP that uses the same DSL carrier, and get them to arrange the switch-over. If your new ISP uses a different DSL carrier, you have to treat this as a complete termination and restart.
Your old ISP usually has to process a release form of some kind, which can be difficult to get if they are uninterested in being helpful.

The phone company offers DSL so cheap! what's the catch?

Some telcos are offering ADSL at great price. They want to own this market. Of course, offering it, and being able to deliver it effectively, are two different things.
Recently, USWest has started offering Megabit Select DSL. This is designed so when you want to use it, it trys to connect if there is a free line, and your contract is designed to allow only a certain amount of connection time in any one period.
Other telcos offer very low CIRs (committed information rate) for their fast ADSL, as they are selling quantity and may not be matching that with back-end bandwidth either themselves or their partner ISPs.
Telcos also do not have a great track record in ISP services, and may even duck out of that completely, so be careful when comparing two products priced differently, that you are comparing like with like.

What is this USF tax?

The USF (Universal Service Fund) is a tax the FCC imposed on long distance carriers, to fund telecommunications expansion in rural areas, among other things.
USF usually appears on your PHONE bill as a small percentage (4%) of your long distance charges, or sometimes (AT&T) a flat rate, regardless of your charges.
Unfortunately, despite the FCC ruling that ISPs are not (yet) contributers to the USF Fee, some ISPs are charging it to the customer anyway, perhaps because they too are charged when they buy some telco services at retail prices (the FCC does not prohibit passing the tax along).
If you are charged a USF on your entire bill, object, as it is clearly profit for the ISP. The FCC itself has hinted that USF should not be passed onto consumers, and is not an internet access tax.

Who do I complain to?

To lodge a serious complaint about an ISP or a Telco (or CLEC), your two forms of attack are the BETTER BUSINESS BUREAU and the PUBLIC SERVICE COMMISSION (PSC) for your state. This may also be referred to as the Public Utilities Commission or the Public Utilities Control Authority. A search should find the one for your state or area.

Read about the BBB on their home page. ISPs that are not going out of business hate the BBB and try hard to resolve issues that get raised there.

The PSC is the only body your Telco is afraid of. Use them if normal dispute resolution is getting you nowhere. Again, your state PSC home page should provide current information on how to lodge a complaint.

What is a reseller? why should you avoid them?

In the DSL world, a reseller is a virtual ISP, it takes your order, and passes it to a real ISP. You may not be told which ISP is actually providing your line.
Resellers are not recommended because
• You are another step away from the people who support your line
• A reseller will normally find the cheapest ISP, which is probably not the ISP you would have picked
• A reseller cannot adequately support you, and yet you are not allowed to contact the real ISP either.
• A reseller may not be in business for the long term, and may be hard to contact if there are problems
• The ISP that controls your line may go broke, and disconnect you, even though you are paying on time.

Getting Complaints Resolved

Besides or in addition to contacting the BBB or Public Service Commission, try writing a letter to the President of the DSL Service Provider or Parent Company. I recently had problems with PacBell (and from the message boards, I'm not the only one), I wrote the CEO of SBC Communications and within a week, they had folks from throughout the organization calling me to resolve the problem.

Answer to question: Can I break a contract?

That question is best answered by calling the company you have the contract with. In most cases however contracts cannot be broken by you unless the company is not performing to the terms of the contract. Since the company usually makes provisions for instances that would negect a contract, it takes alot to get out of them. If the problem is with a Telco you can also contact your states Utilities Consumer Affairs department to investigate the Telco. For Washington State it is: WUTC Consumer Affairs, PO Box 47250, Olympia, WA 98504, 1-800-562-6150. Most cases though you have to give the company notice of what service is not being provided to the contract terms, and time for them to correct it. You may also want to seek legal council depending on the serverity of penalties you might incrue for breaking a contract.

4. Using DSL

I want to operate my own server with DSL, am I allowed?

Servers like web? Ftp? mp3 streaming? Sure, although read your contract first. Some DSL services will forbid servers. Others make it harder. Still others scan for servers and alert the administrators if they find them.. possibly they are monitored and you are asked to explain them if your contract forbids them.

The easy way to find out more is to ask in the forum for your ISP or provider, here on the site.

My IP hasn't changed. Do I have a static IP?

In most cases you probably don't, unless your ISP has stated your service comes with a static IP. Static services are usually more expensive than regular residential dynamic services.

In the example of DHCP, your ISP may have "leased" an IP to you but it will expire after the lease period is over and you will obtain another IP.

Some IP addresses change more often than others, depending upon your ISP, but this does not mean your IP is static.

How can I share my DSL/Cable connection over 2 or more computers?

Sygate is a wonderful proxy program which I use, and it allows you to share your internet connection over 2 or more computers. The url for this product is » and you can try it out for 30 days and if you like it you can buy it. The great part of this proxy is that it is fairly simple to install and allows client computer to view napster, whereas many Proxy's don't allow the use of napster on the client computer.

A more general answer is that there are at least 3 ways to implement internet connection sharing (ICS) among several computers.

The first, and best in terms of flexibility, security and speed, is to use a router. Routers cost from $80 on up, typically in the $150 range at this time. In this setup the router talks to your provider as if it were a computer and it uses NAT (Network Address Translation) to send the proper signals to the right computer on the network (LAN). this is flexible because only the computer(s) desiring connection to the internet need to be on to use it. It is more secure because of the use of NAT, and most routers provide a kind of mini-firewall function; the IPs that the computers are actually on is hidden behind the router; and it is faster than software ICS.

The next hardware solution involves using a hub rather than a router. In this case each computer must have its own IP assigned by your provider and that normally means an extra monthly fee paid per IP. That fee typically runs from $3 to $7 per additional IP. Each computer acts as if it were the only one connected to the internet, so each needs its own firewall and anti-virus software. Speeds to all computers on the network will be about the same as if only one were connected. The biggest disadvantages here, compared to the router solution, are the continuing expense and lack of added security with the purchase of the hub. Hubs run from about $50 on up, with a good one running around $100.

Finally we are back to the software ICS solution. Current Windows platforms (Windows 98 SE, Windows ME and Windows 2000) all have built-in ICS, so the software cost can be zero. There are several other software solutions available for an extra cost. The big disadvantages of this choice are in the areas of convenience and speed. First, the computer acting as the host or server must always be on for any of the others to use the internet. Second, the speed will be reduced to some degree because the host/server computer must process the information to figure out where it should go and then send it on to the proper destination, and it must handle all in and out traffic for all of the computers. The security issue is still there and all systems should have their own firewall and anti-virus software installed.

Ok I have fast DSL, what sites are cool?

Generally, sites with streaming video or audio are good for testing your DSL line and enjoying the bandwidth. The Rich Media category of gives you a selection of sites.

Why is video no better than it was with my modem?

Video streams, for instance the news ones on CNN, are available at rates modem users can cope with. Therefore, you will not notice a better picture when using DSL, or better audio, but you might notice the video no longer stops and starts, and it also starts to play faster. The video feeds on the web usually specify the speed at which they run, for instance, 28k or 56k. I have seen some at 128k, and 300k, but not many.

Should I turn off my DSL or something when I am not using it?

No. Why? It doesn't save you any money. If you concerned about security, though, and don't mind shutting your computer down, it may be prudent. One of the many windows security products called ZoneAlarm is also neat ... ZoneAlarm offers a button; click this when you leave your computer, and it freezes network traffic, unclick when you get back to continue.

Will I get charged more for using DSL often?

No. At the moment, the DSL subscription systems do not usually include usage auditing, or at least usage is not factored into any pricing. This may come though!

Do I still need windows dialup networking tools with DSL?

No, although... if you provider chooses PPPoE, then you will in fact be using the dialup username/password procedure to get a live connection, even if it then stays open until you power down your PC.

Why get DSL when I can dial the office and use its fast line?

If you dial your office, they may have a T1, but you still have a modem, so your internet use travels at that speed.. to say nothing of what your boss thinks about you using the company internet line to play around yourself.

Now I have DSL, I want connect to the office. How can I do that?

Your office would have to arrange a VPN (virtual private network) of some particular type. This allows you to tunnel through the internet and into your workplace, over an encrypted connection. You will need some kind of extra software or configuration on your home computer to use this, and the details vary depending on which VPN product your office picks. Without a VPN, though, you are unable to use DSL to get into work, other than use your companies public home page.

Is DSL available with voice-over-IP so I can use 1 phone line for voice & data?

True VoDSL (voice over DSL) is currently available from a very limited number of providers: for example, Sprint ION, now in beta-test in various areas of the US.
VoDSL seamlessly splits off voice to your phone or phones, taking small parts of the DSL connection for high priority voice packets as you make or receive calls.
With any regular DSL line, just as you did with modems, you may download some of the internet to phone type programs such as dialpad. These programs may suffer from various problems - delay, echo, quality loss etc.

Dont forget that voice & data can be "on the same line" today if you use ADSL provided by the local telco, and soon with CLECs due to a line sharing agreement, regular voice service and ADSL can run over the same physical copper pair. In this sense, yes, 1 phone line is for simultaneous voice and data. But there is no integration between them.

How many users can use a single business DSL line

Depends on the speed. Even a slow speed business DSL line can happily support 10-20 people. Why? because only rarely is more than one person actually USING the connection at a single time.

A T1 speed SDSL line (1500 mbit) could easily support an office of several hundred if their jobs did not involve using the internet all the time.

Getting a good small office firewall like the SonicWall would allow you to set access limits and log users (and abusers) of your office line, so that there is less risk of employees moonlighting at work.

Which modem should I get when ordering from Bellsouth

You should either go for the 3060 internal PCI or the External Alcatel Speedstream Ethernet.

Avoid the USB modems unless you really have a need to (say) connect it to a laptop with a USB port. USB modems take CPU power from the computer, and their drivers are still unreliable.

Can I be dialed up and on DSL at the same time?

Yes. The first problem to overcome is that when you dialup, your DEFAULT GATEWAY becomes your dialup ISP.. the DSL connection is still active though, you just cannot get to it!
Solution (windows):

What is your DSL default gateway IP address? take a note of that. X.X.X.X

What is the IP address of the OFFICE machine you wish to reach?. Y.Y.Y.Y

What is the address of your DIALUP default gateway? Z.Z.Z.Z

Create a .BAT file with the following commands in it:

The first command deletes the dialup default gateway entry.
The second command tells your PC the new default route is your DSL line.

The third command says the default route for your office server Y.Y.Y.Y is the dialup line.

If your dialup has reset your DNS server, you may wish to add another route command

route add A.A.A.A mask Z.Z.Z.Z metric 1

where A.A.A.A is your office DNS server, (assuming it can resolve internet addresses).

Would it slow down my speed if i ran a web server?

Not unless your website is very busy, or contains large files that people frequently wish to download.
There is no traffic, and no speed impact, by just having a web server.
Once setup, web servers provide bandwidth statistics, and you are quickly able to calculate how much percentage of your DSL line is being used by average daily or weekly web traffic.

Are there any alternatives to PPPoE?

Alternatives to PPPoE from your provider: Switch plans or providers.

Alternatives to the PPPoE client software provided by your DSL provider:

Enternet300 -- » sells Enternet300 which may be provided free by your provider, who pays NTS for it's use.

WINPoET -- » does not sell WINPoET to users, only to ISPs.

RASPPPOE -- » *freeware*

And your final alternative is a router that has a PPPoE client in firmware -- which is most of them.

Explain Windows 9x Virtual Memory settings

Setting your virtual memory to 1.5 - 2x your amount of actual RAM is a good idea. Set the minimum and maximum to the same size.

From what I've seen the biggest gain from setting your own settings is that your swapfile does not get fragmented so badly. When you have a dynamic swapfile and Windows decides to make it bigger, it just grabs free disk space wherever it can find it, and this can slow down performance greatly if pieces of a swapped-out program end up far apart on the hard drive.

So my recommendations would be:
1. Set to min/max both be twice your amount of RAM
2. Don't let Windows manage it for you, and
3. Defragment your hard drive!

You should only have to defrag once after you set the manual settings and reboot. This will put the swap file all in one place contiguously, and it won't move around after that.

In Windows 98 and later, defragging also helps make all applications load faster by putting them in the order they actually get loaded so there isn't so much seeking around going on every time you run something.

What is the 80% bandwidth / speed

A general rule of thumb for determining whether or not you have a good broadband connection is whether or not you are getting at least 80% of the maximum possible speed you could. There is a built in 'loss' due to overhead information that must be transmitted and a few other factors that immediately eat up about 13% of your bandwidth (speed). That means that the absolute best in a perfect setup would be 87% of your theoretical maximum. With other factors thrown in, the 80% rule of thumb was developed. Now, how to apply it.

As one example, lets assume you have a 1.5/256 DSL connection. This means that the best you can ever do is to get 1500kbps (kilobits per second) as a download speed and 256kpbs upload. But at least 13% of that is going away for the overhead. 80% of 1500 is 1200kbps, and 80% of 256 is 204.8kbps. So if you have a 1.5/256 line and are getting speds of 1200/204 or better, then you have a 'good' connection.

If you are getting less than these numbers, the DSLR Tweaks forum is a good place to go to start optimizing the portion of the system that can help with these numbers.

A few things to keep in mind: 1) You can only 'tweak' to improve your download speed and hopefully your upload speed will rise along with it; 2) It is hard to apply the 80% rule to an uncapped Cable connection where no upper limit for speed is stated; 3) no 'tweaks' are available to improve Ping (latency) times - that is a separate issue.

how to do dial access and dsl (or cable) at the same time without a script

issue: want to do dial access and dsl (or cable) at the same time.

problem: Windows allows dial access to steal the focus so it is an either/or situation. either you are dsl (or cable), or you are dial access but not both at the same time. there are scripts that allow you to do so, but i am lousy with scripts, and i have to dial in and out all day and hate to run scripts over and over.

my resolution: i run my dsl through a gateway machine via Wingate ... aka the poor man's firewall. For applications that i want dsl all the time (ws_ftp, ie6, media player etc.) I set up proxy settings and "use the proxy". for work (which I use dial access) i go without the proxy.

an example ... i use ns 4.7x for usenet and some email and use dial access to get to the specific news servers so ns is my dial access app. for browsing, searching, whatever i use ie6 and have it setup to connect via the proxy. i can go back and forth between the two ... one 56k and the other dsl.

How Does My Computer Get An IP Address From A DHCP Server?

DHCP involves a four step process beginning with the client (your computer/MAC address) requesting an IP lease. Next the DHCP server makes a lease offer. Then, the client makes the lease selection and broadcasts back that it requests to lease the address in the offer. Finally, the DHCP server leases the address and sends the client an acknowledgment.

4.1 NAT

What is NAT?

NAT stands for Network Address Translation.

To understand what this is, how it functions and why it is needed, we must first cover how the Internet handles communications between computers.

WARNING: Some of the following discussion is simplified and glosses over some of the nit-picking details on how the Internet actually works. For the purpose of this FAQ, the level of detail used is adequate and any statements that are not 100% accurate are intended to avoid needing to go into extraneous detail.

Every computer using the Internet needs an address of the form X.X.X.X (where each X is a number from 0 to 255). Due to the limited number of such addresses, there can be a need for Private Networks with large numbers of computers/devices to have addresses that do not conflict with the Internet Addresses. To fill this need there are certain addresses (10.X.X.X and 192.168.X.X) that have been designated for use on these Private Networks that are not part of the Internet. No computer on the Internet is allowed to have these addresses. When such a network wants to communicate with the Internet it does it though a NAT gateway (which can often also act as a Firewall) All that will be said here about Firewalls is that they are used to control what types of sessions are allowed to cross the gateway. A gateway is usually a computer or router that functions as part of a broadband modem connection, especially in a home user situation.

When a computer wants to talk to another computer on the Internet it starts a session with that other computer. For a computer to be contacted to create such a session, it must "listen" for the attempt to start a session. The listening is done via Port-Numbers (ie: Listen for an attempt to start a session to my "Port Number X"). There is a list of "Well Know Ports" that tell what port number to use to start different types of sessions. For example if you are web surfing, you connect to the web site through port 80. To send email, you'd request port 25.

The contacting computer also needs a port number so that it can receive the responses. This port number comes from a range that is allocated for stating sessions and is unique for the life of that session. In other words, if you are web surfing and have more than one session open, each session has it own unique port number (allowing the browser to know which window to display the incoming information in). The session is defined by its two endpoints. Thus if you have a web session it would be X.X.X.X:5788<->Y.Y.Y.Y:80. If you open another web window and go to that same site, the session might be X.X.X.X:5789<->Y.Y.Y.Y:80.

The forgoing is what happens when the computers are both on the Internet. What happens if one of the computers (let us for simplicity say the one who is doing the web surfing) is on one of the aforementioned private networks and has an address of 192.168.l.50? When it tries to go to the web site, it will try to start a session 192.168.l.50:5789<->Y.Y.Y.Y:80. The messages destined for Y.Y.Y.Y will be sent to a computer that is acting as a gateway (a computer that can talk to both the private network and the Internet and does NAT). On the private network this computer is know as while on the Internet it is known as Z.Z.Z.Z. When the message gets to it, it will alter the reference in the message that says "I am from 192.168.l.50" to say "I am from Z.Z.Z.Z". It will also assign its own port number from the stating sessions range (let us say 7777). Thus it starts its own session of Z.Z.Z.Z:7777<->Y.Y.Y.Y:80 with the web site. It also adds to a table the fact that it's port 7777 is really 192.168.l.50:5789. This is the reason for NOT keeping the real computer's port number. It must be able to tell who it is acting as and using the real computer's port number can cause problems if another computer (such as wants to start a session as 192.168.l.99:5789 (IOW: using the same Port Number as 192.168.l.50 is using). By assigning a port number of 7778 to 192.168.l.99's request the two attempts to use port number 5789 are kept separate.

To the Internet, the two sessions LOOK like they are the same computer (which in reality they are since they are being sent to/from the gateway computer). As each message comes in from the Internet the gateway computer uses the port number in the incoming message to determine who to send it to on the private network and it sends the message to the private network with the correct 192.168.1.X address and port number). Internet directed messages get the same treatment in the other direction (use the table to get the Internet side address and port and send it on its way).

It is all very elegant. The Internet sees the whole private network as being the gateway computer (and is not even aware of the private network) while the computers on the private network see the gateway as the Internet.

Can I share my DSL line with my other computers?


Exactly how you share your single DSL line depends on the operating system on your computer, and recently, whether or not your DSL provider is using PPPoE. With a regular DSL line, with a fixed or dynamic IP address, and microsoft windows, if you wish to share web browsing access but have some flexibility to add ICQ and play multiplayer internet games, then you can use one machine as a gateway, and run a NAT (network address translation) software product like Sygate, or similar on that machine. Current versions of windows 98 even come with ICS, which is a microsoft NAT implementation built-in.
Your private network IP addresses are allocated from the IP ranges internationally reserved for private use (10.x.x.x or 192.168.x.x) and your NAT equipped PC with two network interface cards, functions as the gateway to the internet.
NAT re-uses a single public IP address by allocating unused port numbers for other computers on your private network. NAT also is by default very secure, since it does not allow any incoming connection requests that were not part of a conversation you had initiated, but it can be problematic to setup some network intensive programs over NAT without reading manuals and consulting the net.

Finally, you could buy additional IP addresses from your DSL provider. Most standard DSL solutions will allocate up to 255 IP addresses over the one line.

Can I share my DSL connection on my MAC?


The simple option would be to get an IP address from your ISP for each Mac on your network - but the ISP may charge extra for each address.

Another solution is to run Network Address Translation (NAT) software to share a single DSL connection among multiple computers. Several NAT options exist for the Mac. One very good choice is IPNetRouter, which is cheap, and has a great support community.

Also recommended is the companion line monitoring tool, IPNetMonitor.

Using NAT software, you connect your DSL router to a single Mac (the "gateway") and also connect the gateway Mac to an Ethernet hub. You can then connect other computers (Macs and PCs) to the hub, and they all share the DSL connection.

You can also use Apple's AirPort in this setup so the non-Gateway Macs (and PCs) can be connected wirelessly!

Mac OS X also allows software based internet sharing...
Select System Preferences -> Sharing -> Internet Tab

Sharing with a Hub or ICS, and no router

Yes you can, with just a HUB if your ISP has issued you an IP address for each PC. The DSL modem can be connected to the uplink port of the HUB, if a uplink type port is unavailable on the HUB, a crossover cable is needed. Depending on the brand of router the ISP is using some adjustments might be needed in the router configuration. Most of the adjustments in router configuration will be in the areas of bridge groups and NAT entries.

Additionally, some operating systems provide Internet Connection Sharing (ICS). When you use that type system, one machine must be left on to provide the gateway to the internet for the others.

Sharing with a Router or Switch

If you wish to use a hardware device rather than a dedicated server to share your internet connection, then a router or switch is necessary. If you want to have computers connected together, but appear as only 1 single computer to the Internet (called Network Address Translation or NAT) you need a router. Typical and popular broadband routers include the Linksys BEFSR11 and BEFSR41; the Netgear RT311 or RT314; or the SMC Barricade (SMC7004BR). There are others, including D-Link that I am not personally familiar with.

A hub or switch is something you use to connect computers together on a single network. A router is a device that you use to connect different networks together. You are creating a small network at home. Your ISP and the Internet is a different network, thus the router is the correct device for the job. The router protects your network from nasty packets on the internet by blocking them (which is called being a firewall) and, perhaps more important to the rest of us and your ISP, it protects the Internet and the ISPs network from stuff that happens on your network. Of the above routers, the Linksys BEFSR41, the Netgear RT314, and the SMC Barricade all have a 4 port (10/100) switch already attached to the router, allowing you to plug in additional devices to share the DSL connection. With these systems you can get everything needed to create a small LAN in 1 device.

There are people who will tell you that you can share an Internet connection with a hub or a switch, and they are correct -- it will work. But you can open a can of beans with a hammer, too -- it's just not the right tool for the job. Without going into too much detail, people who share internet connections directly with a switch place a bunch of unwanted traffic on their local subnet that everyone else on the subnet has to filter, and often leave themselves exposed to security risks from the outside world.

Problems with NAT and some applications.

NAT does not accept unexpected incoming connections - it does not know to which machine the data is to be routed.

You must configure NAT for the incoming ports that the server of the program you are using is trying to send you data on.

Most network programs now come with notes for NAT setups, and there are a number of useful pages on the net detailing NAT setups that work with many popular titles.

VPN (virtual private networks) are not comfortable with NAT. Your VPN vendor should provide specialized configuration information. For the popular corporate CheckPoint firewall systems, we refer you to the excellent FAQs at

Why can't I DCC chat on IRC?

When you are behind a NAT firewall, there are a few things you have to do to ensure that you can use IRC. There are several ways of managing this. I'm a former Linksys router user, and I found that when using mIRC, this is the best way:
1. In your mIRC options, under "Local Info", change IP method from "Normal" to "Server". (This gets your actual remote IP, rather than your NAT'd IP, which is sent in a DCC chat request if you don't change it. What would happen then, is in effect, you'd be trying to tell the other person to establish a connection to, which is probably an invalid IP for them, since it's reserved for local IP's.)

2. Set the ports DCC will use in DCC options. (1050->1100 should suffice.)

3. Go into your router firmware, and forward the port range of 1050 -> 1100 to the machine's ip you want to allow DCC access to.

4. For all other computers, set DIFFERENT port ranges and forward those as well.

How do I get NAT to run with SecuRemote 4118 from Checkpoint?

The center of the universe as far as Checkpoint firewalls and SecurRemote is ... in particular, the SecuRemote FAQ which goes to great lengths to explain the problems and solutions for installations of SecuRemote.

I have Proxim Symphony or homefree. Can I use that with DSL?

Yes you can, they are just another way of having a home network: whether it is wireless or wires, makes no difference.. the DSL connection is still your shared connection to the Internet.

How does teamplay Starcraft/ and NAT work?

People have got starcraft "team play" behind NAT working ok using Linux ipchains (which is highly configurable). See, and search in that discussion for "starcraft", otherwise, the general problem of teamplay on a UDP based multiplayer game where the team is behind a single NAT box, can be a challenge for NAT software and equipment.

5. Troubleshooting

Stalls and freezes

If you are getting stalls when using your PC before your new ADSL line has been activated, your new internal card (if any) could be attempting to talk to the network (which is not yet configured for you), and while it does this, your PC may freeze. The solution is to remove the drivers for the card and/or the card itself, until the ADSL line is activated by the Telco, then re-install from scratch.

If your PC is freezing regularly, and you are on PPPoE, your computer may be looking around for a DHCP server that does not exist. Check the following: (Windows)

  • Open Control Panel

  • Open Network and Sharing Center

  • Look for "acces type: Internet", that is associated with a hardware ethernet card (ignore dialup, AOL and VPN type bindings).

  • Select it and press PROPERTIES


  • Is OBTAIN AN IP ADDRESS AUTOMATICALLY checked? if so, change that to USE THE FOLLOWING IP ADDRESS and enter, and, into IP address and subnet mask fields respectively.
    This assignment of a harmless local IP address to the TCP/IP settings bound (connected) to your network adapter, will stop the built-in DHCP services from waking up every 10 minutes to look for a DHCP server so that it can "fill in the blanks".
    Be aware that if you set the IP to manual and then sometime in the future want to use DHCP (eg, Cable HSI for example) you may have problems obtaining an IP address which may result in the following: "invalid ip address".

    In most cases, you will have to do a netsh int ip reset C:\reset.txt in XP, reinstall tcp/ip in Windows 9.x+2000, or at worst cases do a reinstall of the OS.

  • Select the GATEWAY tab. Enter into New Gateway field and click on Add. Click OK.

  • Close all windows and restart the PC.

Also see this thread: Internet freezes momentarily while surfing.

I think my DSL is too slow!

Measuring your DSL speed is not easy. There are a number of speed test applications on the web (our contribution is here), and your ISP may suggest you try a single FTP download, or multiple FTP downloads.

What to do?

First, no single test is enough to determine the speed
of your line
. The internet has weather, as does your ISP, and the server you are downloading from. Weather can delay delivery, as any postman will tell you!

Once you have concluded, perhaps by comparing others' results, that your speed is not what it should be, here is a check list of things to worry about if you have a DSL line. For cable users, we have an excellent cable FAQ that may help you identify coax noise that could be slowing you down. cable tech faq.

    •Line quality test. If you have not done so already, try one of the two different line quality tests we offer on our tools page. Smokeping is open to all users, the line quality test is open to registered users. Both will show up a noisy line - one that is suffering from packet loss that can interfere with the smooth transfer of data.

    •ISP Weather. Your ISP may be suffering a "brown-out" at the time you tested. Only once consistent slow results, or a pattern, can be established, can you rule out temporary brownouts by your ISP.

    •Internet weather. More rarely, the internet as a whole, at key choke points, can become slow. Perhaps there is a fiber cut, or some router failure. Internet storms such as these rarely last long if they are big. But smaller, more local storms, may be more persistent.

    •ISP Routing. Larger ISPs have many options to route you onto the net, and at times they may be sub-optimal for you or your area. Normally this goes hand in hand with much higher than expected latency than you should expect.

    •Backhaul. Backhaul is the path of your data between you, and your first visible hop. To get to your first hop, your data may have to travel from CO to CO and even be carried across country to get to your ISP. All of this is invisible to you, but poor backhaul routing does result in high latency to your first hop, or worse.

    •DSL Interference. DSL operates across a wide frequency spectrum, and particular ADSL and G.lite, can vary speed downwards in response to noise on the line. There are often no user visible statistics on whether this is happening, and the only symptom is poor performance. Checking around the house for possible sources can sometimes reap rewards of immediate speed gain. Things such as poor house wiring, long home phone cable runs (rather than locating the DSL modem as close to the entry point of the line as possible), or in the case of ADSL, micro-filters of insufficient quality, or being installed backwards, older fax machines, or poor quality phone extension handsets. Even cordless phones and floro lights should be regarded with suspicion. By a process of elimination though, you can determine which if any of these possible problems is the cause of your persistent poor speed.
    One of our users adds: "Using an older NAT box (e.g. a linksys older than 2 years) can dramatically shrink throughput. In my case, direct connect averages around 9Mb while through the linksys I peak around 3Mb"

    •Home alarm systems, installed "in-series" to your phone line, can ruin an ADSL signal. placing them on another run with a filter should be a top priority.

    •Slow computer, USB modems.. CPU can be a factor in speed tests, particular java driven ones. Anything less than a pentium 100mhz CPU, and anything less than windows 98 cannot be trusted with more user-friendly speed tests. Even a basic computer, using command prompt FTP, should be able to outrun even fast DSL lines though. USB modems, particularly ones entirely software (driver) designed, consume CPU, and should also be considered as possible sources of slowdown.

    •Poor or dubious quality ethernet card. Even though the ethernet card is the most simple and proven part of the whole DSL setup, some no-brand type ether cards, especially when paired with doubtful or older ether drivers, can cause an interesting array of performance or other weird problems.. things such as web pages being viewable, but uploading failing, for example, has more than once been traced to a dodgy ethernet card.

    •Card conflicts. Especially with internet DSL modems, interrupt/slot related difficulties with windows and drivers can cause problems that are solved by re-arrangement of cards, or by removal of cards that are not needed. Stripping a PC down to the minimum when testing may quickly identify this as the source of any frustrating problems.

    • Home alarm systems, installed "in-series" to your phone line, can ruin an ADSL signal. Placing them on another run with a filter should be a top priority. This comment is actually the way it's designed to work. It's called 'seizure' - the process of ensuring 100% access to the phone line in the case of an alarm condition. The ideal scenario is to use a POTS splitter so that the phone and internet service is SPLIT before it gets to the demarcation block. This ensures that the alarm is connected to the PHONE side of the line without affecting the MODEM side (connected to the ADSL modem) of the line. This will allow an alarm to still have 'seizure' and also 'share' an ADSL line with an alarm system on the phones, WITHOUT FILTERs. Filters are generally poor quality and fail on occasion, but a pots splitter has much less likeliness of failure or accidental removal. Moving an alarm to an 'extension' defeats the 'seizure' of the telco line invalidating any assurances of reliable transmission. (This bullet point suggested by Jeruvy See Profile)

How do I optimize my MTU and RWIN settings?

The most important thing you can do to your PC to maximize broadband performance is to optimize your MTU and RWIN values. Before you make any changes run a baseline speed test to a reliable test site and record your results...then get tweaking!

MTU (Maximum Transfer Unit)
MTU is the maximum packet size (in bytes) that can be transported reliably across any particular network; IP Ethernet in this case. The maximum size of an IP Ethernet packet is 1500, but overhead like IP, TCP, and PPPoE must also be taken into account. The wrong MTU will actually prevent you from accessing some web sites or FTP sites. It may even cause you to not authenticate properly on mail servers or secure web sites. There are too many variables to be able to estimate what your optimum MTU should be, but there is an test that can determine your correct MTU.

Important Notes:
•If you have a network with multiple PCs every computer should be set up with the same MTU. Additionally, some PCs may use several Network Adapters or a VPN client adapter on one PC so you must verify you are changing the Network Adapter associated with your broadband service or VPN client.
•Due to additional overhead, some VPNs may require an MTU that is much smaller than the results of the ping test. The best way to eliminate MTU as a possible source of the problem is to lower the MTU to 1200 and test the VPN connection. If it functions correctly at 1200 increase the MTU until the VPN stops working properly and use the largest size MTU that did work. Additionally, some VPNs create separate network adapters so be sure to select the correct adapter when changing MTU size.
• The built in PPPoE client for Windows XP uses an MTU that can not easily be changed or set manually. The MTU is set to 1480. For more information please reference this XP MTU article. This only applies if you are running the built in XP PPPoE client!

Although the Broadband Reports Tweak Test offers very good general information, it may give erroneous or misleading MTU recommendations and its information should not to used. Since it simply looks at whether you use PPPoA or PPPoE, it can not give accurate, individualized MTU analysis. To guarantee the proper MTU customers should use the following procedure:
    Go to the MTU Ping Test and record your results.
    Change your MTU using DrTCP (see example below) or any similar registry editing application. Remember, you must change the MTU on the correct network adapter (if you have more than one) and you must reboot your machine in order for the settings to take place.

RWIN (Receive Window)
The TCP Receive Window can be thought of as the main data gate keeper to your computer. It sets the limits on the amount of data that can be received before it must send an acknowledgement and broadcasts that to the sender. If the number is too low you will tie up bandwidth with frequent and unnecessary acknowledgements. Too high of an RWIN will create a slowdown if any packets need to be retransmitted.

There are mathematical calculations that can be used to obtain your optimum RWIN, but they are complicated and rely on variables that can easily change. I suggest using real-life testing with some guidelines from the Tweak Test:
    Run the Tweaks Test using the correct FastAccess Tweak Settings and record the RWIN recommendations. FYI: The recommendations from the test are very accurate and usually the highest recommended value is perfect for many users.
    Record the "MSS Requested" number (possibly 1452 or 1460) shown in the left column of the results. Note: All RWIN values should be an even multiple of your MSS.
    Change your RWIN to the highest recommended setting (roughly 37,000) using DrTCP (see example below) or similar registry editing application. Remember to change the RWIN on the correct network adapter (if you have more than one) and reboot your machine in order for the settings to take place.
    Retest your download speeds and record any changes.
    Retest again using the next higher or lower RWIN value until you find your optimum speeds. Note: When trying different RWIN values make sure you use even multiples of your MSS.
    For example:

    1452 MSS
    x 26 Even Multiple
    37752 RWIN

    The next lower RWIN value would be:

    1452 MSS
    x 24 Even Multiple
    34848 RWIN

Changing the MTU and RWIN values
You can download and use DrTCP or any similar registry editing application to change your MTU. An example of changing the MTU using DrTCP is shown below. (Figure 4)

Pictures by Andy Houtz

Note: If you have more than one network adapter on a PC you must change the MTU on the correct network adapter associated with your broadband connection. You must reboot your computer in order for the new MTU settings to take place. Additionally, if you have a network with more than one PC, all computers and the router must have the same MTU setting. Please reference the links below to learn how to change the MTU on some popular routers:
MTU change on a Linksys Router

I cannot access the net at all.

All of a sudden, your computer is not online any more. What basic steps can you take to diagnose what is wrong?

A variety of problems can be the cause of "net down".

The first thing to check is power, lights and connections. If there are lights to check, are they all green? If they flash with activity, are they flashing when you attempt to use your browser? The modem may be trying to tell you something. Refer to your manual on lights or status information.

If you're running Microsoft Windows, a reboot is often the first thing to try unless you have evidence that the problem lies elsewhere.

General tests are, first, try to ping a well known server, like Netscape. Open an MSDOS prompt, type ping and press return.

NOTE:(Make sure the server you pick to ping responds to ping! Many servers now do not, and you should not confuse that with a network problem).

If you cannot resolve the name to an IP address (ping will hang for a while or may fail with cannot resolve hostname type errors), then ping a known good IP address. The IP address of your local ISP is a logical start. It is always useful to have some key IP addresses jotted down for simple diagnostics like this, unless you have a good memory for 4 part numbers. If you can ping an IP address inside your ISP, congratulations, it is not your DSL line.

If it is your DSL line, you may be able to call the ISP and get them to try to ping you, which should start them on solving your case, otherwise your ISP maybe able to inform you of a network problem they are having.

Got my DSL Modem but no Sync!

Wait for your install date. Be patient and it may come on early.

Check the filters on the devices. EVERYTHING but the DSL Modem on your DSL phone line MUST have filters or it may keep you from getting sync/not be stable/slow. Don't forget items such as the phone line into your cable/satellite TV decoder, etc.

I keep losing sync. How can i stop this?

There are a few things could cause this. Your DSL modem may be malfunctioning. If this is the case you should call your ISP and tell them to replace your modem, or, if the modem is yours, either have it serviced or replace it.

In order to determine whether the problem is inside your home or outside, take your modem to the NID (Network Inteface Device) and connect directly. This eliminates any inside wiring.

If you are able to sync up fine outside of your house at your Telephone box (more commonly known as the NID, Network Interface Device) Then your inside wiring will need to be inspected. You will have to notify your telephone company and tell them to fix the problem. Note this will cost you money because it's outside of your ISP/DSL service.

Your telephone line could be losing quality. Line noise, electronics on the line, or a short on the line can break up a sync signal. You will have to tell your ISP that you keep losing sync and want to have your line checked for problems. They should open a trouble ticket with your ILEC/CLEC and they will inspect the lines. In most cases they can find the problem this way.

My DSL disconnects when I answer the phone

This is a symptom of bad internal wiring, or problems with filters, splitter or sockets.

Another possibility is an MTU on the line. An MTU, is a Maintenance Test Unit. In days long gone, it was used to remotely check for problems on your phoneline. It seems these lovely units that consist of an Op-Amp and a bunch or resisters, capacitors, etc ... cause major problems with DSL. These are generally located in your phone closet or basement (where the phoneline comes from the street into your house/apartment).

You can have your phone company do a line check and they should be able to determine if you have one on your line and approximately where it is located.

Some other possibilities suggested by our members:

1. If a customer's DSL goes out when they answer an incoming telephone call, it's not always in the house wiring. Have your local phone company check the CO for what we call a half tap. If they find one that should solve your problem.

2. If the water company's automatic reading unit in your basement is connected to your telephone line, it may be causing issues. Unplug the phone line attached to it and you can see if this is the case. They may contact you advising they can't read your water meter. You can advise them it is causing issues with your DSL and they will hopefully address the problem.

Web-sites seem slow on initial connect

The usual answer to this is DNS resolution, or some problem with name resolution.

When you give the name of a website, your PC must communicate to a DNS server to resolve it to an actual IP address. If your ISP is having DNS server difficulties, this resolution process may take time. Subsequent resolutions may be quicker because the ISP DNS server has now cached the name.

If your DNS server exhibits very slow response, and consistently so, then contact your ISP to ask them to investigate.

Another source of slow DNS queries is how your PC may be resolving the location (IP address) of the web address you enter. From an command line window, you can use the NSLOOKUP command to test name resolution speed. Pick a website that you have never visited (perhaps from a newspaper advert or something), then type 'nslookup'. The delay before the IP address of that site is returned should be no more than a few seconds, perhaps for some small and slow websites, the delay could be 5 seconds or so. If the delay is consistently much longer for new sites than these estimates, your PC may be trying to locate the name of the site via several methods before your ISP DNS server is queried.

(Windows) The cause for this is possibly the presence of a number of networking protocols and clients in your networking setup, which cause the PC to attempt name resolution first locally (using netbios), then via your ISP.

The local attempt will fail, but not until after a timeout period. If you are in doubt as to which protocols may be safely removed, ask a question in our forums.

MSIE Work Offline / Try Again

Some software installs, for example Enternet, can make MSIE lose knowledge that you are connected full time to the Internet.
  • Solution 1 .. Try Repair:
    Go to control panel, add/remove programs, find explorer 5.5, highlight that and click REPAIR. After the reboot, it should be fixed.

  • Solution 2 .. Quit any PPPoE service (Enternet Access Manager/WINPoet) etc first.
    Look in the registry
    Using regedit, find the folder:
    And check that these two *String* keys are set to auto:
    Create them if necessary!

One of our visitors added this bit of information which might be of help to others:

I recently had this problem when using a Windows 2000 machine with IE6 and a DSL connection. I had recently added VPN support which shows up in the Settings -> Network and Dial-up Connections area of the Start Menu. The VPN connection settings were under Incoming Computer Connections. I had tried all of the LoadLCE/Load ... =Auto options and I had even repaired a registry key that Windows 2000/IE6 corrupts from a DWord to a Binary setting ( see ). None of these "fixes" corrected my problem until I deleted the Incoming Computer Connection under the Network and Dial-up Connections menu. Once this VPN connection option was deleted, the Work Offline/Try Again box has not re-appeared.

Another added this:

You can also try selecting the "Never dial a connection" radio button instead of deleting the VPN/Dialup connection.

My ADSL line cannot send AND receive at advertised rates

ADSL lines that are much faster download than upload do not do well when simultaneous uploads AND downloads are required. To operate the download channel at full speed, a large portion of the upload channel is required. If the upload channel is busy with something else, TOTAL throughput can drop severely as the competition for resources slows down both activities. Users have also reported that streaming video both in and out at the same time results in very poor throughput - much lower than one would expect looking at the speeds available. There is not yet any recommendation or information on what can be done to get around this problem, other than changing to a DSL service with more symmetric capacity.

Why can I not ping my IP address?

First you must distinguish between Public IP address and Private IP address. Your public IP address is that which the world believes you are on. Your PC private IP address may be something else entirely.

You may find your public IP address by using the BroadbandReports IP tool: /ip.

Your private IP address is that reported by your PC. For example, in Windows,
Start->Run->Winipcfg (or "ipconfig /all in a command line window)
will bring up a utility that describes the IP address the PC has. Be careful, your PC may have several IP addresses!

If you cannot ping your public IP address, it may be because the machine this represents simply does not respond to ping.If you cannot ping your private IP address, you may have installed a firewall that refuses to acknowledge ping packets.

If neither of these cases apply, you may not have correctly identified your public or private IP address.

Why Does My Computer Stop Responding Using USB Modem?

Your Windows 98 Second Edition Computer May Stop Responding or Experience Slow Download Times with a USB (Universal Serial Bus) Modem. This problem is resolved in Windows Millennium Edition (ME).

» ··· ;q240947

You have to contact Microsoft Tech Support to get them to email you a download link to their FTP server for a "hot" fix mentioned in KB article Q240947.

Why do I have long delays after rebooting with Win2K and WinXP?

If you are using PPPoE and you experience a long delay after rebooting, your network adapter may be configured to use DCHP.

Try assigning an internal IP address to the Local Area Connection that corresponds to your network adapter.
Control Panel -> Network Connections -> Right click on your Local Area Connection and select properties -> Click on TCP/IP and select properties.

Now insert as the IP address and as Subnet Mask. Leave default gateway blank.

Now go back to Control Panel and select Administrative Tools -> Services -> DCHP and select disable DCHP.

I can browse, but can't download any files.

Being able to browse but not download is usually caused by NIC problems. Move your NIC to a different PCI slot. If that doesn't work, take out all unnecessary PCI cards like sound cards and 56k modems, and then try each slot. If it works, then you can add the other devices back until you find the problem. You can move the device causing a conflict to a different slot and that may fix the download problems.

I'm getting Error 650... what should I do?

Try what is called "power-cycling" ...

    •Shut down your computer.
    •Unplug the the modem from the USB slot, and unplug the phone line from the modem.
    •Wait about 2-5 minutes.
    •Plug everything back up, and restart your computer. •Reconnect, and everything should run smoothly again.

Why can't I game with my new Router?

More than likely you have to go to the "forwarding" part of your router setup and forward the corresponding ports.

The following three links contain some detailed information about which ports to forward and more. Each link has different, but very helpful information to explain and help guide you through the process.,1202066;root=equip,16;mode=flat

I am unable to connect to some sites recently.

When you connect to some servers, they have to be converted into an IP address in order to connect. A file called HOSTS stores these IP addresses. When the address changes it becomes invalid and you are unable to connect to that website.

To fix this:
1. Close all browsers. Go to Start, Find and select Files or Folders.

2. Find a file called "hosts" (without the quotes) that has no extension and rename it to hosts.bak.

3. No reboot is necessary. The changes are immediate. If this does not fix the problem, then likely it is trouble with the owners.

How do I know if my DSL problems come from my house or my telco?

If you have access to your outside test jack (where the main line from your telco connects to your home line, usually via a standard sized telephone jack), find a long phone cord and run it from your DSL modem to the outside test jack directly. This bypasses all of your internal circuitry.

If you were unable to connect before and are still unable to connect, your ISP probably has a problem (perhaps a bridged tap or numerous other line quality destroyers). Call your DSL service provider or phone company and ask them to check.

If you were unable to connect before due and are able to connect after doing this, the problem is likely inside your house. Your telco probably offers professional installation of a DSL line splitter, which would eliminate internal problems. (I will post information later about self-installing a separate DSL line on the same phone number).

Why do downloads start FAST, then slow down?

Actually, they're not really slowing down. After you click on the download button, the download begins while you're typing in the file name. If you take a while to do that a considerable amount of data will be saved before the download speeds start registering. That's why it seems to be zipping along at first. But, after the buffer has caught up, it will then start showing your true download speed. Speed too, will fluctuate as the servers that you're downloading from get busy, and you'll get speeds going up a little, then down a little.

Don't forget, it's important to make sure your computer's optimized for speed. Be sure to check out DSLReports Tweak Tools at /tools for tools to help you tweak your speeds, and be sure to check out the Tweaks forum for more useful information!
submitted by Santa Fe

What can I do to get better performance out of my DSL connection?

This is free advice so please take it if you need it.

Often we as customers complain about our service and wonder why no one seems to be doing enough. Have you done enough? We expect our DSL provider to bend over backwards to bring us a better connection when often we have made little or no such effort on or own end.

Do you have a POTS splitter?

Please keep in mind that the device you plug into your phone jacks all over your house are not POTS "Plain Old Telephone Service" splitters but filters and if you are doing this all of your non DSL lines under your house are counting in your total line length and are robbing you of bandwidth. A POTS splitter goes inside of or next to your SNI/NID which is usually a gray or black box located outside where your phone line comes into your house. On one side of the POTS splitter is DSL and the other side is POTS or voice this keeps the DSL signal from running in all of your other lines under your house which will add to your line length. POTS splitters run from around forty dollars and up and depending on which one you buy and where it may be a module that fits in your SNI/NID or a separate box all together. I recommend getting the module type and personally use the LPF-200 by antec products. You can find some nice examples of how this is done here and for older SNIs here. Be sure to take out that half-ringer since it can add to the length of your line.

Do you have a dedicated or "home run" line?

Dedicated or "home run" means that the line for your DSL runs from the SNI/NID to the wall jack or interface for your DSL modem and nowhere else and it is best to have no other devices installed on this line. It is also best to use CAT5 "category 5" cable to run your dedicated or "home run" line. You can use any of the four pair to do this and it is often suggested that you use pair number two or the orange and white pair. You can also go the extra mile by running CAT5 from your wall jack or interface to your modem of course you will have to do some trimming "cut some of the other wires back" to allow it to fit into the module plug.

Always remember these important rules while routing ANY CAT5 cable:


Never stretch your CAT5 cable.


Always keep your CAT5 cable at least six inches away from ANY other cables this is VERY important for electrical cables as this will cause more noise on the line. If you are a bad judge of distance a dollar bill is usually six inches.


Never un-twist the pair any more than one half of an inch, one quarter of an inch is even better if you can get it connected. The same goes for stripping it including the outside jacket.


If you have to cross other cables do so at a ninety degree angle.


Never crush or kink your CAT5 cable. This includes stapling your CAT5 cable. Use hangers for such purposes which you can get from radio shack or staple wire ties which you can get almost anywhere.


Make sure you don't run your CAT5 into a spike or surge protection device as there are sometimes problems with these like you didn't know your new puppy likes to pee in it. =o) It also should not be needed as SBC should have such protection in your SNI/NID already.

Are you sharing your dsl with others in the house?

Invest in a DSL gateway or router as ICS, Sygate and other software alternatives just don't do as good of a job and cause you to have to leave a computer on so the other computers can use the connection. If you only have one IP a gateway will do just fine. Make sure that what ever you purchase will support PPPoE "point-to-point protocol over ethernet (RFC 2516)". Most that are made for DSL do but it is always a good ideal to make sure since many of the europe DSL providers use PPTP "point-to-point tunneling protocol (RFC 1171)" or PPPoA "point-to-point protocol over ATM (RFC 2364)". DSL gateways can be purchased for as little as thirty dollars depending on where you shop and how much security you are looking for most of them offer NAT "network address translator (RFC 1631)" protection at the very least and are well worth the investment. Also most of them have a built in DHCP "dynamic host configuration protocol (RFC 2131)" server that makes it easy to use multiple platforms without all of the setup nightmares.

Are your settings correct?

Your MTU "maximum transmission unit" and RCVWINDOW "receive window" are the most important but you should not ignore the rest. If you are not getting one hundred percent transfer efficiency on the DSL-Reports tweak test it is probably your settings and they offer some helpful advice there. I usually obtain best results with an MTU of 1500 and an RWIN of 65535 but your results may vary depending on your line conditions. The DSL-Reports tweak tester is here

Do you have noise on your line?

If you have noise on your line it may be RF interference you can find good information on tracking it down here.

Remember if you refuse to go the extra mile then you can't expect others to do it either and you will find if you have most of the techs will be able to get to the root of your problem much quicker.

Thanks to everyone whose fine post I have used in reference here and DSL-Reports for such a fine resource. I couldn't have done this with out you.

My latency (ping times) are high, even though my transfer rate is good

If your latency is consistently high, you need to question your provider as to your routing. Many ISPs are not national, but are able to sell DSL nationally. In certain cases, they must route traffic all over the place even if you are trying to use local game servers or sites.
In other cases, the ISP has real (and hopefully temporary) routing problems, or a critical failure and they are on backup.
Normally network specialists plan for optimal routing, but during fast growth, your ISP may have got into a situation where customers pay penalty in ping time while the ISP figures out how to resolve the problem.

The first step in diagnosis of high latency is to figure out the ping time to your default gateway. You may do this by using the Line Quality tool at this site, or by using Visual Route from Datametrics (

If your default gateway ping is good, the next step is to get a trace to a server that you believe should be nearby.
Ideally, nearby servers are available with a few number of hops and low total latency.

What can you do if faced with persistent high latency?

Unfortunately, nothing. ISPs are not obliged to operate with any minimum latency guarantees, so vote with your feet. Discussing the problem with as senior a technical support person as you can find may reveal they have expansion plans that will ease the problem in your area.

I added a DSL internal modem, now my PC crashes

When this is not an outright hardware failure, it is usually a device resource allocation problem. (this advice applies to windows PCs only). Open the control panel and get the System icon open. Look in the device list, and check if there are any devices windows has marked with a red cross or any other type of error symbol. Just because there are not, does NOT mean that there are no conflicts!! This is most important to learn! many devices come with poorly written drivers, which do not accurately reflect the hardware. This can mean that windows "overlaps" the resource use with another device resource map without "realizing" it. Resources are scarce (otherwise they would not be called resources) so usually if windows can make this mistake it will!
The end result can be a range of mysterious symptoms: video card corruption, mouse pointer freezes, speaker clicks, keyboard freezes, disks seek and re-seek, and activation of the cdrom causes disk activity. The introduction of DSL to a system often requires the introduction of a new card, either ethernet or a DSL modem card.. and this is a good chance for uncovering device problems. The simplest solution is to remove all the devices from the PC that you can (other modems, sound cards etc), then reboot windows and confirm the problems have gone away. Then add back or enable (in the case of motherboard devices such as USB ports), until the problem comes back. If you can narrow it down to two conflicting cards or devices, refer to websites for updated drivers to see if that fixes them.

I lose line Sync regularly

Frequent loss of line sync (the normally green light on your DSL modem goes out, blinks, turns yellow or red, and the Internet is suddenly unreachable) can be caused by:
  • Line noise
  • A faulty modem
  • A line card problem at the CO DSLAM
  • Frequent CO DSLAM upgrades that are not communicated to you.
If the problem is regular - for example, at roughly the same time almost every day and it lasts for some time, you should investigate whether or not local line interference is the root cause. This could be: street lights going on, local transmitting towers of any kind, lights or electrical devices in or around the home that are possibly routed near your inside wiring. Unfortunately, having successfully guessed this cause, it is often very hard to correct ... even another copper line might have the same problem.

If you suspect modem malfunction, check for heat. Replace the modem if you can. If it is an internal modem, change slots and try running with minimum other internal cards. (Remove SCSI cards, Soundblaster cards and so on.) This is to verify that the root cause is not a plain old Windows hardware conflict.

If all else fails, it may be a marginal card in the CO DSLAM that is causing your line problems. Suggest (although this might be ignored) that the DSLAM card be re-seated, or that you be swapped to another card.

At least one user has reported that not enabling DMA on his hard drive was the cause of his sync problems.

How come I can't register a user name and password on SWBell over the internet?

This MIGHT be due to the fact that you entered the information wrong on the application. Check this first. But if you repeatedly get a message saying something like "We are sorry, but our server cannot register you right now, we may be experiencing technical difficutlies, try again later" this could be due to a mis-communication between ASI and SWBell. The first thing i would do is call up ASI and have them register you over the phone. This is fairly simple, and they will give you a temporary password. If they encounter trouble with this, such as they can't find that you are registered to recieve dsl, have the person on the phone contact SWbell and check you account information. If your account information was not processed correctly, you will be unable to register, which could lead to some major headaches. If this still does not work, post your problem in the forum area under "swbell" and you may get a response that helps you out.

I've tweaked, tested, and I still have problems, how do I deal with my ISP?

Answer 1: First, do you want or need to continue
dealing with your current ISP?
Some people can simply and easily move to
another ISP and immediately get better service, but often there are fewer and
sometimes worse options for most of us. If you have a contract, you might not be
able to do this without paying a penalty. Then again, the stress of dealing with
long-term complicated problems can make moving on worth every penny you might
end up paying to get away.

Answer 2: If you want to stick with your current ISP,
make sure you tried everything in the book to fix your problem; tweaks, testing, isolating your computer and DSL modem, disconnecting everything in the house, anything at all that might have the slightest effect on your connection. Also take into account external forces on your DSL, like
that new AM radio station that just went up next to your house. ;)

Broadband - especially DSL - is very complex, and the issues surrounding it are not always understood well by DSL providers. Consequently your ISP's limited and costly support resources are often over-burdened, which can make it very hard for them to respond to you when you really need the help.

Many DSL problems can be difficult to correct because there are often at least 3 different companies that have their hands in your DSL connection: Your ISP, Telco, and network provider. Since these companies may not let you communicate with anyone else but the ISP when you have a problem, resolving a problem with your telco or network provider may require a lot of persistence, patience, and hold times with your ISP.

Since in the end you may need to call your ISP for help, follow these instructions. Sometimes you'll get through to exactly the right person,
and sometimes you will speak to Satan himself. You should know how to deal with them both:

1. Keep a record of every call on a fresh sheet of paper. Write down the time and date, the name of each person you talk to during that call, get their direct number if you can "in case we get disconnected", and write a brief description of the events during the call. You may have to talk to several different technicians during one call, so don't be
surprised if you get bumped to a higher level of tech support - be thankful, and write down their info.

This may seem like a lot of work but in the end it will be worth it especially if your problem requires a complex solution, and also if it involves people who prove to be a
hindrance to getting your problem resolved. I guarantee you will not even remember the name of the tech after 5 minutes, and keeping track of what you've already tried will help you narrow down future problems as well as the current one.

2. Be polite, be persistent, and be patient with the people you talk to.
Technical support call center jobs are often very stressful, and techs are usually overworked and under quotas to get as many calls completed in as short a time as possible. Getting angry with them doesn't do you or them any good, and your problem will probably not be resolved immediately anyway if you tried everything else before the call.

3. If you follow Step 2 religiously but the person you are talking to is abrasive or is refusing to help resolve your problem, you should stop dealing with them and demand to speak to their
manager immediately - be polite, but firm. You WILL be put on hold at this point. If
the hold time goes on too long (15-30 minutes) then hang up and call Customer Service (not Technical
Support). Calmly explain the problems you had with the previous tech, and request to speak to a manager.

4. If you speak to a Manager, remember that they
are even more over-worked than the phone techs are, but they usually know
their employees: they can and probably will assign you to a better tech to
help get your problem resolved. If they are good at their job, they also want
to know if and where their employees need improvement - just be truthful when
you relate your experiences with a bad tech.

Repeat Step 4 as necessary until you get to someone who
cares enough to take charge of your problem and work it through with you.
There is nothing stopping you from demanding to speak to a higher authority if
all else fails, but as with everything else in life, the higher you reach the
more difficult it is to get there.

5. If you've tried everything and aren't
getting the help you need
, you can try contacting the ISP's CEO, and then
service agencies that regulate the industry. This can actually have quick
results, but don't expect anything instantaneous:

  • Try writing a letter to your ISP's CEO or other
    corporate executives
    . Many people actually have gotten positive
    results this way

  • Your Public Utilities Commission may help you.
    Below is the California web site address, but others may easily be found
    using a search engine such as

  • Contact the FCC Consumer Complaints: 1-888-225-5322

6. Failing all else, cancel your current ISP and go
with another provider.
If you have tried your best, and still can't get
what you need, then either there really is no current solution to your problem
or you need to move on to another ISP or broadband provider.

If your ISP can't provide you the service you contracted
for, they are effectively in breach of the contract you both agreed to and
they should not penalize you when you cancel. Though this has potential to
turn into a battle over billing, your documentation of calls and letters will
help you much more in this event than if you didn't keep track of anything at

Content-Disposition: form-data; name="previewed"


What can I do to ensure clean lines for my dsl connection?

Call your local telco and have them test your phone lines. Even have them come out to your location. It's their job, don't let them tell you otherwise.

Problems continuing to use my old (dialup) email

Although you may still have an old dialup ISP account with active email address, you may have problems using it from your new DSL line.
Some ISPs do not let people send email (a process not normally password authenticated), from outside their network. Others require that you fetch first then you may send.
The solution is to forward your old email account to your new DSL ISP email address, and only send email as your new account. When everyone has updated their address books for you, you may deactivate the old email account entirely.

Why can't i set my MTU to 1492 with WinPoet?

Search your registry for TunnelMode, change it to 0. Re-boot, you can now set your mtu above 1454

Why does my modem take so long to sync with the CO?

Your connection seems to work well, but it takes way too long for your modem to sync with your CO (over 10 minutes, up to hours), such as after power up.

Reasons for slow sync with the CO:

1. Telephone surge suppressor in the circuit between the modem and the phone jack, such as those found on a UPS or power strip.

2. No micro filter installed between phones and the telco line. (Applies to splitterless installations.)

3. Poor line quality.

4. Problem with modem in CO.

To troubleshoot slow sync, follow these steps:

1. Disconnect all phones and other equipment from your phone jacks.

2. Make sure that the phone line connection to the modem is direct. Do not wire through any surge suppressors.

3. Power up the modem. It should sync with the CO within 5 or 10 minutes.

4. If it still won't sync, call your ISP to report the problem. Your phone line has it's own modem at the CO end. There could be a problem with it. Or there could be a problem with your line.

Once your sync time is OK, plug in each of the phones or other equipment one at a time and check modem sync by power cycling your modem. With splitterless setups, make sure there is a micro filter between each phone and the phone jack.

My home alarm isn't turned on-will it still affect my DSL signal?

Yes, it will. It will act like any other un-filtered device plugged into your telephone line. An exceptionally strong DSL signal will overcome this, but the best bet is to pull (or have pulled) a new wire from your network interface to the DSL jack. And this new wire needs to be unfiltered!

When I pick my phone up, I get a static feedback when the modem synced

If you are running ADSL (voice over data lines only) and hearing a screeching feedback pulse (sounds like when you pick a phone up while dialed-up), your line needs filters.
You should place an ADSL Microfilter on every phone you have at the jack, but not the jack the DSL line is plugged into. Most in-line microfilters can be found at your local computer retail store for under $15. If you have a wall-mounted phone (ie: older rotary phones) you must buy a different type of filter than runs for around $30.

In-line filter:

Wall mount filter:

Can't access some Web/FTP/Secure sites & troubles with email/VPNs/file transfers

If you are able to access almost all web sites but have any or all of the following symptoms your MTU (Maximum Transfer Unit) may be incorrect.
Can not access certain web sites or see particular frames within a website.
Can not access web sites or sections of web sites that require a username and password (i.e. banking, stock quote, online ordering, etc).
Can not access or download from certain FTP sites.
Can not access certain servers or information while using a VPN client.
Can not access web based email sites or send/receive emails.
Can not access POP based email or send/receive emails.
Can not send/receive file transfers.

To find the correct MTU for your configuration you must run a simple DOS Ping test. Please reference the following steps:

The command for this ping test is ping -f -l xxxx.
•There is a single space between each command.
•"-l" is a lower case letter L, not the number one.
•The last four numbers are the test packet size.

Open a DOS prompt screen by clicking on Start>Programs>MSDOS-PROMPT. You can also use the Run Command by clicking on Start>Run then type in "command" for Windows 95/98/ME or "cmd" for Windows 2000/XP.
At the DOS Prompt type in ping -f -l 1472 and hit Enter. Notice that the packet needs to be fragmented. (Figure 1)

Drop the test packet size down (10 or 12 bytes) and test again. Notice that the packet still needs to be fragmented. (Figure 2)

Drop the test packet size down more and test again until your reach a packet size that does not fragment. (Figure 3)

Once you have a test packet that is not fragmented increase your packet size in small increments and retest until you find the largest possible packet that doesn't fragment.

Take the maximum packet size from the ping test and add 28. You add 28 bytes because 20 bytes are reserved for the IP header and 8 bytes must be allocated for the ICMP Echo Request header.

An example:
1440 Max packet size from Ping Test
+ 28 IP and ICMP headers
1468 Your optimum MTU Setting

You can download and use DrTCP or any similar registry editing application to change your MTU. Remember, if you have more than one network adapter on a PC you must change the MTU on the correct network adapter associated with your broadband connection. Additionally, if you have a network with more than one PC, all computers must have the same MTU setting. Note: You must reboot your machine in order for the new MTU settings to take place. An example of changing the MTU using DrTCP is shown below. (Figure 4)

Andy Houtz

DSL Error Code Identifications

DSL Error Code Identifications

Error Messages
600 An operation is pending.
601 The port handle is invalid.
602 The port is already open.
603 Caller's buffer is too small.
604 Wrong information specified.
605 Cannot set port information.
606 The port is not connected.
607 The event is invalid.
608 The device does not exist.
609 The device type does not exist.
610 The buffer is invalid.
611 The route is not available.
612 The route is not allocated.
613 Invalid compression specified.
614 Out of buffers.
615 The port was not found.
616 An asynchronous request is pending.
617 The port or device is already disconnecting.
618 The port is not open.
619 The port is disconnected.
620 There are no endpoints.
621 Cannot open the phone book file.
622 Cannot load the phone book file.
623 Cannot find the phone book entry.
624 Cannot write the phone book file.
625 Invalid information found in the phone book.
626 Cannot load a string.
627 Cannot find key.
628 The port was disconnected.
629 The port was disconnected by the remote machine.
630 The port was disconnected due to hardware failure.
631 The port was disconnected by the user.
632 The structure size is incorrect.
633 The port is already in use or is not configured for Remote Access dialout.
634 Cannot register your computer on the remote network.
635 Unknown error.
636 The wrong device is attached to the port.
637 The string could not be converted.
638 The request has timed out.
639 No asynchronous net available.
640 A NetBIOS error has occurred.
641 The server cannot allocate NetBIOS resources needed to support the client.
642 One of your NetBIOS names is already registered on the remote network.
643 A network adapter at the server failed.
644 You will not receive network message popups.
645 Internal authentication error.
646 The account is not permitted to log on at this time of day.
647 The account is disabled.
648 The password has expired.
649 The account does not have Remote Access permission.
650 The Remote Access server is not responding.
651 Your modem (or other connecting device) has reported an error.
652 Unrecognized response from the device.
653 A macro required by the device was not found in the device .INF file section.
654 A command or response in the device .INF file section refers to an undefined macro
655 The macro was not found in the device .INF file section.
656 The macro in the device .INF file section contains an undefined macro
657 The device .INF file could not be opened.
658 The device name in the device .INF or media .INI file is too long.
659 The media .INI file refers to an unknown device name.
660 The device .INF file contains no responses for the command.
661 The device .INF file is missing a command.
662 Attempted to set a macro not listed in device .INF file section.
663 The media .INI file refers to an unknown device type.
664 Cannot allocate memory.
665 The port is not configured for Remote Access.
666 Your modem (or other connecting device) is not functioning.
667 Cannot read the media .INI file.
668 The connection dropped.
669 The usage parameter in the media .INI file is invalid.
670 Cannot read the section name from the media .INI file.
671 Cannot read the device type from the media .INI file.
672 Cannot read the device name from the media .INI file.
673 Cannot read the usage from the media .INI file.
674 Cannot read the maximum connection BPS rate from the media .INI file.
675 Cannot read the maximum carrier BPS rate from the media .INI file.
676 The line is busy.
677 A person answered instead of a modem.
678 There is no answer.
679 Cannot detect carrier.
680 There is no dial tone.
681 General error reported by device.
691 Access denied because username and/or password is invalid on the domain.
692 Hardware failure in port or attached device.
698 A response keyname in the device .INF file is not in the expected format.
699 The device response caused buffer overflow.
700 The expanded command in the device .INF file is too long.
701 The device moved to a BPS rate not supported by the COM driver.
702 Device response received when none expected.
707 X.25 diagnostic indication.
708 The account has expired.
709 Error changing password on domain.
710 Serial overrun errors were detected while communicating with your modem.
711 RasMan initialization failure. Check the event log.
712 Biplex port is initializing. Wait a few seconds and redial.
713 No active ISDN lines are available.
714 Not enough ISDN channels are available to make the call.
715 Too many errors occurred because of poor phone line quality.
716 The Remote Access IP configuration is unusable.
717 No IP addresses are available in the static pool of Remote Access IP addresses.
718 PPP timeout.
719 PPP terminated by remote machine.
720 No PPP control protocols configured.
721 Remote PPP peer is not responding.
722 The PPP packet is invalid.
723 The phone number, including prefix and suffix, is too long.
724 The IPX protocol cannot dial-out on the port because the computer is an IPX router.
725 The IPX protocol cannot dial-in on the port because the IPX router is not installed..
726 The IPX protocol cannot be used for dial-out on more than one port at a time.
727 Cannot access TCPCFG.DLL.
728 Cannot find an IP adapter bound to Remote Access.
729 SLIP cannot be used unless the IP protocol is installed.
730 Computer registration is not complete.
731 The protocol is not configured.
732 The PPP negotiation is not converging.
733 The PPP control protocol for this network protocol is not available on the server.
734 The PPP link control protocol terminated..
735 The requested address was rejected by the server..
736 The remote computer terminated the control protocol.
737 Loopback detected..
738 The server did not assign an address.
739 The remote server cannot use the Windows NT encrypted password.
740 The TAPI devices configured for Remote Access failed to initialize or were not installed correctly.
741 The local computer does not support encryption.
742 The remote server does not support encryption.
743 The remote server requires encryption.
744 Cannot use the IPX net number assigned by the remote server. Check the event log.
752 A syntax error was encountered while processing a script.
769 : The specific destination is not reachable. (According to Microsoft this behavior may occur if the network card in your computer is not turned on [enabled].)

How do I change my DNS server address(es)?

How do I change the DNS server address(es) in Windows 95, 98, or ME?
    •Click the Start button > Settings > Control Panel.
    •Double click on the Network icon.
    •Under the Configuration tab, there will be a list of items. Select the TCP/IP item that corresponds to your Ethernet adapter, then click Properties.
    •Click on the DNS Configuration tab, and remove all entries under DNS Server Search Order.
    •Under DNS Server Search Order, enter the DNS Server Address(es) you wish to use, clicking on the Add button after each one.
    •Keep clicking OK until all the dialog boxes are cleared.
    •You must reboot for this change to take effect.

How do I change the DNS server address(es) in Windows 2000?
    •Click the Start button > Settings > Network and Dial-up Connections.
    •Right click on Local Area Connection then choose Properties from the pop-up menu.
    •Click Internet Protocol (TCP/IP), then click the Properties button.
    •Click Use the following DNS server addresses and enter the DNS server address(es) you wish to use.
    •Keep clicking OK until all the dialog boxes are cleared.
You do not need to reboot for this change to take effect.

How do I change the DNS server address(es) in Windows XP?
    •Click the Start Button > Control Panel > Network Connections.
    •Right click on Local Area Connection and select Properties on the pop-up menu.
    •Click Internet Protocol (TCP/IP), then click the Properties button.
    •Click Use the following DNS server addresses and enter the DNS server address(es) you wish to use.
    •Keep clicking OK until all the dialog boxes are cleared.
You do not need to reboot for this change to take effect.

5.1 ISP Specific FAQs

AT&T Broadband



An Earthlink start page.

Optimum Online




Streamyx (Malaysia)

Basic Ontario/Quebec DSL ISP Services Info

(note: this applies mainly to DSL customers in Ontario and Quebec)

- NO ISPs Can only provide 256k (going up to 512k soon), 3Meg and 5Meg residential services (6Meg biz).

- NO - All ISPs dealing directly with Bell Nexxia have their own network infrastructure (ie: transit, routers, etc...)

- YES - All ISPs using Bell DSLAMs must go through Bell's copper and authentication cloud in order to provide DSL

- YES - All ISPs must pay for dry copper services (pricing is based on band rates A to G)

- NO - Bell is only obligated to a Service Level Objective (SLO) to the ISPs (not an SLA)

- 48+hrs Bell has a 48hr SLO waiting period before ISP staff can escalate. From there a 12ish hour period can be expected before further escalations, and so on and so forth

- NO - ISPs can not control the connections speeds at lesser costs (ie: if bell gives ISP 3Meg, ISP can't shape to 1Meg and charge 1/3 less... ISP pays 3Meg rate and the same, if an ISP requests a profile change lowering the speed of a client lower to stabilize a connection. Original rates per original speed apply.)

- YES - ISPs require accurate Circuit information on 3rd party telephone providers in order to provide DSL service over the Bell copper.

- NO - Clients 'can not' call Bell Nexxia as the ISP is the client of Bell Nexxia, not the client (therefore information provided to a client will not be accurate/consistent... ISP/Nexxia database isn't the same as Bell Canada/Sympatico nor is the phone number to discuss problems).

- YES - Sympatico/Bell can solicit 3rd party ISP clients and is only obligated to a 90 day waiting period (Bell has an internal policy of communicating with all the households in Ontario and Quebec 4 times per year! - Might even be Canada wide).

-DOUBT IT Bell gets the lions share of a DSL account! Currently an ISP can expect to pay Bell on average between $21 and $24 per account per month for 3Meg service. This excludes bandwidth, hardware, network, HR, software, etc., so, many accounts are required to make ends meet on $30/month accounts. Unless Bell drops the rates this will likely be as low as it gets.

- 5+ DAYS The ISP places the order into the Bell Nexxia portal and a minimum 5 business days can be expected to wait. ISPs must wait at least 5 business days before opening any tech support related tickets on new orders.

- NO Only Bell authorized personnel are allowed to do so, therefore ISPs can not accelerate the install process.

- BELL/CUSTOMER! If a client has problems in a certain city but is A1 everywhere else (often seen in the forums), then at 99% of the time the problem is on the Bell or customer end. There are very few circumstances where this is not the case.

- YES ISP feeds for providing DSL services come in over VLAN, provided by Bell. ISP can only monitor feeds within its realm so anything prior to it is monitored by Bell only. As a result, if a Central Office, or even an entire City is down it is likely the ISP will be notified by the client before Bell.

- BLACKLISTING Nearly all major ISPs block certain ports (in particular port25) in order to lower the risk of having their main IPs black listed. A MAJOR problem for ISP is being blacklisted as it can sometimes take days before being removed

- NO ISP simply provide a connection service and for those who use email a temporary holding ground for emails. The only things ISPs track are IPs to identify internet access history (ie: we can tell when a specific individual was online).

6. Security

If I am on the net 24hrs a day, will I get hacked?

Short answer: probably not. Longer answer.. probably not because you are one of millions of computers and there are not enough hackers to go around. Anyway, any spare ones are not interested in your digital family photo album or excel expense worksheets... but they could get to your files if you don't care to learn about security.

You should check the The Security FAQ of this site for more information on security, and how to secure your home computer.

NAT offers good security, because by its nature it does not allow incoming connections, it is for sharing an IP address amongst several computers for outgoing purposes only.

Apart from NAT, basic security is to have a router with firewall features, that only allows in what you decide to allow in. Your DSL connection options usually include the choice of a router. Although not strictly speaking a full firewall, a router is the first line of defense against intruders. With the modern router, setup correctly and refusing to route any requests by outside IP addresses for inside resources, things are a little tough for the hacker. However, you may want to open things up a little more, for example to allow yourself to telnet into your own computer from other places, run an FTP service, or your own web server. In this case, you need to look carefully at (a) the security setup for anything that is "public", (b) encrypting any files you really care about, and (c) avoiding transmission of any passwords in plaintext form.

If you are doing anything serious with your DSL connected equipment, it is also a good idea to look at getting or writing some kind of small monitoring system that will play cop inside your own network.. like a ignition cutout on a car, these can be simple, yet very unobtrusive.

Using Linux how can I make my computer safe?

The first thing is to delete the default usernames and passwords.

Next you can and should change your root username to something other than "root". It's also a good idea not to always log in under and use the root identity.

If you work in an office you should always engage a screen lock or go to the log-in screen so your co-workers can't edit your files while you're away.

If you're at home you might choose not to give root passwords to your children.

You should also look at your logs frequently to make sure hackers aren't attacking your system and forgetting to clear their entries in the log.

You could install a hardware firewall or just a router so you won't have a public IP address.

Finally you could install a NAT box.

For more information on this and other *nix matters, see the All Things Unix forum.

Is my line DSL line private, or can my hacker neighbor listen in?

Unlike cable modems, your DSL is totally private, up to your ISP. It is possible that your ISP can monitor your use of the web, but no more likely than if you use a dialup modem. Note: this does not mean you cannot be hacked by someone else on the internet, it just means that you have a separate line from you to your ISP, so no local neighbors can listen to your data.

Where can I read more on Security, is a large section that deals with security issues and products for Cable/DSL connected visitors.

Do I Need a Firewall? Which is best?

"Good fences make good neighbors." With your new broadband (DSL or cable) connection, your computer is potentially visible to others on the internet every moment it has power applied to it.

The general concensus is that cable users are more vulnerable than DSL subscribers. But no one without a firewall is without risk.

A good firewall makes your computer invisible, or at least less visible, to others on the internet. There are other users that will try to probe your machine looking for ways to see what is on your computer's hard drive. Some may only be curious, but others may be trying to be very malicious - even to the point of erasing files on your system. They could potentially gain access to your passwords and other private information you may have stored in files on the computer.

You may ask 'which is the best firewall'. There are special setups that actually involve hardware and these hardware firewalls are considered the best choice. The down side of the hardware solution is cost. Many users therefore choose to install a software firewall. These have the advantages of low cost and easy setup. Which solution is best for you is a question you have to answer for yourself.

The most common windows firewall right now is ZoneAlarm, although there are many others. Check Security pages for more details.

My firewall keeps alerting me about connections. What should I Do?

You must determine what the alerts are trying to tell you and make your decision based on that. The answers are different for alerts on outbound traffic than for alerts on inbound communications. Each alert is almost a unique situation by itself. When you have specific questions about specific alerts quite often you will find an answer on the Security forum here at DSLReports. When in doubt, deny the connection, if possible, until you can find out just what it is all about. Better safe than sorry!

I have Norton Personall firewall or any other software firewall, am I safe?

You can use Probe Shield in the Tools section to determine if you are protected or if you have any holes in your security system.

Properly set up, most personal software firewalls provide a good level of protection. Unfortunately, in December, 2000 the Gibson Research Center released a test program called LeakTest that showed vulnerabilities in most major software firewall programs. Norton Personal Firewall was one of those. The only major software firewall to not fail the LeakTest testing was ZoneAlarm. It should be noted that Symantec immediately began making changes to their Norton line of firewalls to patch the holes found by LeakTest. As of this writing, those changes had not been implemented or released. (When this situation changes, if someone will Instant Message a moderator, this comment will be edited to remove this notice).

Is ZoneAlarm a worthwhile firewall or spyware?

ZoneAlarm is a very worthwhile software firewall program. It is most definitely not spyware. ZoneAlarm has won high praise from both the several million people and companies that use it and from several industry publications. In December, 2000 the Gibson Research Center released a simple test program called LeakTest that showed vulnerabilities in several other major software firewall products, but which ZoneAlarm was not vulnerable to. ZoneAlarm is simple to install, use, maintain and for personal or non-profit organization use it is free.

What is a Trojan?

The word Trojan comes from the classic Trojan Horse in Homer's Iliad. In this story the Greek left behind a large wooden horse outside the city of Troy and sailed off. The citizens brought the wooden horse into town. The horse contained Greek warriors, who then jumped out, killed a bunch of people, and opened the city gates, letting in the rest of the Greek army who had been hiding.

A Trojan generally is not by definition a virus and unlike common belief they do not spread to other programs and other computers like a virus either. However they are one of the leading causes of computer breakings. They can also contain a virus within them.

Trojans are generally programs that pose as a legitimate program on your computer and add a subversive functionality to it. That's when it's said a program is Trojaned. For example a Trojaned login program can be written so it accepts certain passwords for any user's account to give the intruder access to your computer. A commonly used program called Toolkits is actually a suite of several Trojans that can be put on a Unix machine by an intruder. It contains a password sniffer, a backdoor program to let the hacker back in to the machine at any time, replacement binaries for common programs and finally a log cleaner to cover its trace.

Trojans can contain a virus, a password grabber or they can be a RAT (Remote Access Trojan) that is designed to allow remote control over your system. Some Trojans contain built in scanners that automatically scan the Network from your computer, looking for another copies of themselves. The most commonly used Trojan is The Sub 7 Trojan. What makes it common and dangerous is the fact that unlike other Trojans that are written once and forgotten, Sub seven's author provides constant improvements and new versions for his Trojan. This Trojan can be really destructive or just annoying.

Remote access Trojans such as Sub 7 consist of two parts. One part that resides on the victim's computer and the Control module that resides on the Intruder's machine. Using the control interface the intruder can take control of your computer, flip your background picture, Speak out of your speakers, reboot your computer or do serious damage to your machine and do pretty much whatever he or she chooses.

How can I become infected with a Trojan?

In most cases people are infected by Trojans as a result of opening an email attachment, transferring files over the ICQ and similar services, or by opening binary messages on Newsgroups . They can also be transferred using ActiveX or Java programming but this is not a common method. By having a current Anti Virus program that detects Trojans and a good firewall such as Zone Alarm that prevents outgoing calls you can be relatively safe both from being infected and from being accessed by the Intruder if you are already infected.

How can I find out if I am already infected by a Trojan?

Hard question to answer. There are several kinds of Trojans and each do a different thing. Always look for strange behaviours by your computer. It's a good idea to be pro active and every once in a while look at all the programs that are running in the background and look for strange or unfamiliar program names. It is also helpful to always look for listening ports on your machine. You can do this by typing Netstat -an in a command prompt (DOS) session. Look for ports that are marked " listening " and compare those port numbers with several Suspected Trojan port lists available on the Internet or seek help from other DSLR members in identifying the purpose of those ports.

I am infected with a Trojan. How do I get rid of it?

There are several kinds of Trojans and each may have a different effect on your machine. Trojans are mostly recognized by most up do date virus scanners, however once the Trojan is executed, it will make several changes to your registry and configuration which are not easily detected by virus scanners and can't be cleaned automatically. By identifying the class of the Trojan you are infected with and visiting the web site of your favourite Virus Scanner, you can find step by step instruction as how to clean your registry entries and other configuration changes made to your machine. however some Trojans can't be cleaned with anything less than a clean format. So remember being pro active and running a good virus scanner and firewall would always be an easier task than cleaning a virus or Trojan.

How can I find out if I am already infected by a Trojan?

One, get yourself an AntiVirus package.

If you don't have the money to get yourself one, you can go to and use their free online virus scanner.

If it doesn't find one and you still think that you have one on your system, download The Cleaner and scan your system with it.

What TCP/UDP ports should be left open on a firewall?

Where possible, no ports should be left open.
Open ports on an as-needed basis, perhaps for games, IRC, ICQ, streaming video, web server etc. If you have no idea why you should open a port, and have no problem to solved, then no ports need opening.

Am I being watched by my ISP?

Maybe, some ISPs don't even have privacy agreements. These broadband ISPs (mostly cable modem vendors) have been known to sell detailed information about their users, including name, address, and lists of URLs visited.

Even if your ISP does have a privacy agreement, they may still sell detailed information as long as it doesn't contain identifying information such as your name and phone number.

What type of security does a DSL line provide?

None. It is up to the enduser to supply that security.

how do i make my pc pingable

If security or other tests report that you are unpingable, the reason is most likely a setting in either your firewall or, if you have one, your router. You will need to determine where the signal is being intentionally dropped and make the changes there. The best way to get help in this process is:
If you have a firewall, visit the DSLR Security forum.
If you have a router, visit one of the equipment forums dealing with your brand of router.

What is a dummy DMZ?

Basically a dummy DMZ is a fake non-existent LAN IP placed in a router's demilitarized zone. Some people have used this technique to send all unwanted traffic from the WAN (internet) side of a router into "nothing". Most people use this to give stealth results when security scans are run. It can also be used to make you stealth while also being pingable.

Is there a difference between a IDS and a firewall?

Yes there is a very large difference.

An IDS (Intrusion Detection System) may only detect and warn you of a violation of your privacy. Although most block major attacks, some probes or other attacks may just be noted and allowed through. An example of an IDS is Black Ice.

A good firewall will block almost all attacks unless specified otherwise or designed otherwise. The only problem is, the firewall might not warn you of the attacks and may just block them. An example of a firewall is ZoneAlarm.

It may be a good idea to have both an IDS and a Firewall, because the IDS will warn you and then the firewall will block the attack. Some Firewall/IDS's are combined into one internet security program, for example Norton Internet Security. This is a very well designed combination of both a firewall and IDS.

7. DSL 301

How do I determine my IP ADDRESS?

You can do this here on the site - just go to this page, where you can click on the button to get your IP address.

A more standard method is by using ipconfig in windows, or ifconfig in *nix.

With Windows, open a command prompt window (Start -> Run -> type cmd) and type ipconfig. You will see your present IP in the results.

The program winipcfg that was familiar in the Windows 9X series doesn't exist in Win2K/WinXP.

You can download a handy little application called wntipcfg to replace it. More info here.

Direct link to download:

To simplify things, when you finish installing, you can go to the folder where it installed and rename the file from wntipcfg to winipcfg and put that file in the c:\windows folder. Then to use it, use -> Start -> Run - type in winipcfg and the old winipcfg will pop up and will work! Easy for those used to winipcfg.

Thanks to djdanska for updated info on this entry.

Anything wrong with picking a distant ISP?

Picking a distant ISP that has no local facilities will not decrease the speed you get from your DSL line, but will increase the latency (the time taken to traverse the link to a given internet site).

Latency typically matters for gamers, for programmers using telnet sessions, and possibly for applications like voice over IP (internet phone) applications. It is possible that an east coast user that has ordered DSL from a west coast ISP may find ping times to an internet site in their own city could be up to 100ms more than a neighbor who picked a local ISP or one with local facilities. 1/10th of a second is not much, but is certainly a drawback for advanced interactive gaming.

What is interleaving? Is it better on or off?

Interleaving is an extra level of error correction.

It makes sure that all ATM packets that come from the DSLAM to you and from you to the DSLAM are not corrupted, and if any are, it forces a re-send.

Having Interleaving off may introduce packet loss depending upon how clean your line is. If it is a rather clean line, packet loss may be as low as 3%, but if it is a dirty line, packet loss may be as high as 50%.

Having Interleaving off does have its advantages though. It lowers your ping times for instance, and also makes playing in multiplayer games more enjoyable since multiplayer games don't require that all packets reach the destination.

How do you set interleaving?

Interleaving is set by the LEC on the DSLAM for your service, so the only people who can change the interleaving settings are the physical provider of your service.

The exception to this is the Cisco range of ADSL routers, where interleaving can be increased or reduced, if you have the enable password for the router.

Increasing latency by setting higher interleaving rates means your connection is less vulnerable to noise. Decreasing latency by decreasing interleaving may cause connection drops.

Recently, Covad is allowing ISPs to request Interleaving be disabled for their ADSL circuits, reducing ping time considerably. If you are not sure whether Interleaving is off for your ADSL line, contact your ISP and ask.

What is a Redback Server?


Redback is not only the name of the server, it is also the name of the company that makes the server. Their website is here.

In other words, Redback is only the name of the router. These are DSL Routers. There are several companies that make DSL Routers, Redback is only one. Others include Juniper, Cisco, and more.

The major significance of Redback is that it receives the ATM Cells right from the ATM Cloud and is able to strip away the ATM Cell and retain the RVPI/RVCI information so it can route the packets back to the specific customer that requested them. Redback is essentially a gateway into the Mindspring Network.

During authentication, Redback checks with Radius to make sure that a customer has access to our network, and to assign that customer a Mindspring IP address. Redback associates that IP address with the customer's RVPI/RVCI information and this is how it is able to retrace the information about where on the other side of the ATM Cloud it should send the response to a request.

After authentication, Redback knows that a customer has access to use us as a gateway into the internet cloud, so it passes internet requests on to a Cisco router and then out into the Internet Cloud. From that point on, Redback acts as a liason between the ATM Cloud and the Internet Cloud, making sure that packets get routed to the right customer, or that internet requests get sent on to their respective location in the WWW.

How can I get a DNS name with Dynamic IP?

One solution is a neat service called Dynamic DNS.

It allows someone with a dynamic IP to have the ability to auto update your DNS account with a client that you can customize with your own update settings.

When you have everything installed and running properly, the service will auto update the DNS server every time your IP changes. What makes this good is that the TTL (time to live) is set to 60 seconds, so that after your IP changes, within 60 seconds your DNS name would be updated. What the client does is send the new IP to the DNS server and monitors for new IP changes.

Compare bridged vs Routed DSL

As the name implies, a bridge connects your local network, to the ISP.. the ISP network may comprise many other DSL subscribers. A bridge has little built-in intelligence, it passes all data it sees on one side of the bridge, to the other side, no matter whether that is the correct destination for the data or not.
Bridged networks are simple to setup when small, but with more and more subscribers, they can start to waste bandwidth with "noise": packets of data that are not meant for you.
Noise on a bridged network should not be confused with the traffic on a shared ethernet, on a bridge, only certain categories of data (broadcasts and ARPs) are passed to network nodes by the bridges, nevertheless, as the size of the bridged network increases, broadcast traffic can rise to be a significant fraction of the link bandwidth. Network configuration problems can also give rise to "storms" where links are flooded with packets making communication difficult.
Routed DSL places a router at your end, and the router "knows" about your network, and also knows about the router at the other end (at the ISP), meaning that it passes traffic that is yours, and destined for the internet, over your link.
Routed DSL, if available, is a more expensive option than bridged DSL, and is normally only provided in a business DSL package. Business DSL packages have higher quality of service guarantees, and these can be better met with routed DSL. Routed DSL is also slightly more secure, as it is harder for intruders who are on a nearby address to impersonate machines or snoop traffic.

What is the difference between T1 and 1.5mbit SDSL?

A T1 line and an SDSL line uses the same underlying technology - HDSL. The differences between them are not in performance, they are in ease of provisioning and speed of repair.

In the US, lines for T1 data are normally treated as higher importance by telcos, than DSL lines, so time to repair and provisioning can be considerably faster. A T1 fault may be repaired within hours, or a day, whereas a DSL line fault could be a 5 day turn around time.

The other important difference is that T1 lines are more easily repeated to cover longer distances, something that has not yet happened for SDSL lines.

T1 lines are significantly more expensive than DSL lines, a monthly T1 lease, with internet bandwidth, can amount to $1000 or more, compare that with SDSL prices of a few hundred dollars for the same speed.

T1 lines are often provisioned with a service level agreement (SLA) that may include guarantees on the speed, and reliability of the service, maximum time to repair, compensation in the event of an outage, and so on. A 1.5mbit SDSL line will generally come with an SLA that is less favorable to the customer.

What are the pluses and the minuses for usb and nic connections for adsl modems?

USB plus: no need for ethernet card.
USB minus: USB software drivers may not be as stable as an ethernet/external modem setup. All USB devices need significant CPU power to control, especially when in use. No possibility of insertion of "USB firewall" in between the USB modem and the computer. Harder to try out other operating systems. Newer releases of windows may require a driver upgrade that is not available for a period of time.

Getting into the SpeedStream 5260

To get at your Efficient Networks SpeedStream 5260:

1st) Verify that the TCP/IP protocol is installed and your IP is set to 10.0.0.x and subnet mask is set to or (both work)

Q:How do I Verify my TCP/IP Settings?

A:right click on Network Neighborhood (assuming your using Windows 98), then properties. The Network window opens. Scroll down to find TCP/IP - 'your network card' (be aware there may be more that one if you have a dial-up connection. that would look like TCP/IP - Dial-Up Adapter). Click on that listing. click on Properties. The TCP/IP Properties window opens. Select the IP Address tab. Here you can see your IP Address & Subnet Mask.

Q:How do I install TCP/IP, because its not listed for my network card (NIC)?

A:In the Network window that you have open, select the Add... button, select Protocol, then Add... Now, in this exact sequence, select Microsoft from the right side and TCP/IP from the left (you may need to scroll down). Now click on OK. At this point it wil ask you for the Windows 98 CD and eventually want to restart you computer.

Q:OK, TCP/IP is installed, how do I put in the right settings?

A:refer to 'Q:How do I Verify my TCP/IP Settings?' to get to the right place. Once you click on the IP Address teb, select SPecify an IP address:, then in IP Address: type and in Subnet Mask: type (note: a couple of different settings work here, as I mentioned above)

2nd) Telnet to your SpeedStream 5260 on

Q: How do I Telnet? [Moment of truth!]

A: (again in Windows 98) click on Start, then Run... Type 'Telnet' without the quotes. A Telnet window will open. It also may try to connect to your ISP (I'm using RASPPPoE and the Dialup Connection widow opens... Just hit the Cancel button). You should see 'Command-)' in the Telnet window. FYI, the connect process only should take a couple of seconds. If it takes longer, it probably won't connect. If that is the case, verify that you don't have any other devices on your network using as the IP address. Also, verify you TCP/IP setup is correct. I have seen mention that the install tech's may disable a telnet session in. I don't ~believe~ that is possable, but I do know that the IP address or subnet mask can be changed. If that is the case, good luck, because I have no answer to that.

3rd) Run commands in the telnet session.
A:its pretty basic. Use the '?' to get help, either general or specific. For instance, at the 'Command-)' prompt, type '?' (with out the quotes, of course) and hit Enter. you should see:


Command Description


show Shows system information, status, IP configuration

set Sets configuration parameters

delete Deletes NAPT server entries, routes, or PVCs

default Sets various parameters to factory defaults

clear Clears statistics

reboot Reboots the router

firmware Downloads new firmware to the router

getconfig Set router configuration from a file

putconfig Save router configuration to a file

quit (exit, logout, logoff) exits command session

logout (exit, logout, logoff) exits command session

logoff (exit, logout, logoff) exits command session

exit (exit, logout, logoff) exits command session

atmping Tests the ATM link by transmitting an OAM loopback cell

ping Sends datagram round-trip to specified IP host

traceroute Traces the route (hops) from the router to an IP

This is a list of all the top level commands. You are able to type some of the commands without any options. For instance, type 'show' to see the General Bridge Information. Or type 'show ?' to see its options

Some commands do need the options, though. Now type 'set ?' and you'll see:


Command Description


bridge Enables or disables the bridge function

bridgefilter Enables or disables bridge filtering

bridgemac Enters MAC address into the bridge filter table

dsl Sets DSL interface state to reset, connected, or disconnect

ethcfg Sets the Ethernet communication mode

ethip Sets Ethernet IP address, and network mask

hostname Sets the system hostname

ipgateway Sets the IP gateway (default route)

password Sets a new password for the router

spantree Enables or disables spanning tree

vc Configures virtual circuits

This is a list of all the second level options. To see what a specifc command does type 'set ethip ?' and you'll see:


usage: set ethcfg (full | half)


Allows configuration of the data transmission direction of

the Ethernet interface. The interface can be set to 'half'

(one-way transmission at a time) or 'full' duplex (transmission in both directions at once). The default setting is 'half'.

I believe you can use this notation to get help on every command avaliable in the router, although I haven't tested every command

BTW, the 'set ethcfg full' command shown above is the only thing that I have changed on my SpeedStream 5260. This ~should~ help if you have a full duplex NIC. DO NOT use if you NIC is half duplex or you are unsure.

Warning: Changing some of these settings my make it impossiable to connect to the internet. I cannot take any responsibility for any changes you might make. Be sure to save or write down every change so you can change it later if it doesn't work. USE AT YOUR OWN RISK.

Lastly and optionally, remove the TCP/IP... binding from you NIC in the Network window (find you NIC, click properties, then click Bindings, then uncheck TCP/IP) as I have found that if TCP/IP os bound to my NIC, whilw I am on the internet, there will be a 30Sec. pause every 5min. or so. This will remove the TCP/IP protocol from you computer (unless its bound to another NIC) and wil prompt you to restart. At this point you will not be able to
telnet to the SpeedStream 5260, unless you add TCP/IP back.

Now that you know how to get in, post any SpeedStream 5260 speed or security tweeks that you come up with, as the only one I've know of is setting it to Full dulplex.

Can I share my PPPoE ADSL connection without buying multiple IPs?

You can set up a system with with the DSL modem in it and a NIC for your LAN and install a proxy program such as AnalogX Proxy to share the connection.

If you have an external Ethernet modem, you can put two NIC (Network Interface Cards) so that there is one NIC for your ADSL line and one NIC for your LAN, and install a proxy program such as AnalogX Proxy.

Or you can buy a router such as a NetGear 311 or LinkSys (this option will only work if you have an external Ethernet modem).

8. Home wiring


If you have a home alarm system, do not put your alarm box in series with your incoming ADSL line!

Home security systems with dial-out alert capability are often installed IN-LINE.. in other words, your telco line comes in, goes into your alarm box, comes out and continues to your junction box. The alarm system, whether active, standby or unpowered, is not providing you with a clean connection.

Although you can get DSL Sync with this method, the Alarm system can attenuate (reduce) some of the high frequencies required for high speed, leaving you with poor performance or worse. Isolate your alarm system behind microfilters, or on the voice circuit behind a splitter, as you would any other phone in your house.

A SWBell user (David Taylor) passed us these two diagrams.
Original setup, Modified setup, that solved his persistent speed problems.

What is the best wire to use for phone / network / digital cable?

Using Category 5 (cat5 or cat5e) cabling for networking and phone will be your best bet. For cable you always want to use RG6 type cable, NOT RG59!

If you have a chance to wire your own house and feel comfortable drilling holes, pull two cat5 cables and one RG6 cable to everywhere a computer or T.V. will go. The best cable for a cable modem is Quad shield cable. It's expensive but it's the best.

Can I still use DSL and dialup on the same computer? Does it require a splitter?

As long as you have both a DSL modem and your regular modem installed on your computer, and the DSL signal connected to your DSL modem, and just your voice signal connected to your modem, using DSL and dialup on the same computer is not a problem. (although if you are dialed into the internet, then that will be the primary connection until you disconnect).

What is inside wiring?

For CLEC provided DSL (ie, DSL through Covad, or Northpoint), It is the process of taking the line from the drop, where the telco left it, to a socket on your wall. This may involve running new lines at your premise, but this process is no more painful than adding another phone extension. For ADSL, inside wiring is handled by the Telco as part of the whole install deal. Where the Telco and the CLEC must cooperate with wiring, there can sometimes be extensive delays and difficulties, none very technical, usually a lack of coordination.
For older apartment buildings, there may be much bigger problems, if there are no spare pairs available for non-Telco DSL, new wires may have to be run in the building, adding to the expense, time delays and trouble.

Where can I get a RJ45 (8 wire) DSL Line conditoner for my home security system?

You don't. You get a DSL-POTS splitter ( is the only place I know that retails one) to place between the Telephone Network Interface Device and your existing telephone wiring. You then run a separate inside wire and jack from the splitter to your DSL modem.

how can my dsl line be good up to the house yet bad on the inside?

The wiring that is on the streets or underground is of very high quality wire, therefore, the ADSL signal is almost always at full strength.

Unfortunately, if you have bad wiring in the inside of your house (multiple splices (if you are going to splice, learn the "Western Union Splice"), wiring draping near fluorescent lights, near sources of high amounts of electromagnetic radiation (such as electric wires), or just bad quality of wiring), you will lose some of the strength of the ADSL signal, thus decreasing your overall bandwidth.

If you have any of the above things happening, reroute your wire, install new wire without splices (remember, telephone equipment uses very low amounts of voltage, and everytime you splice, there is a chance to lose some of that low voltage), or replace your wiring.
Answer #2:
There are many factors that can affect DSL performance in your house. First thing to check though is that you have installed the DSL Line filters properly on every phone, fax, modem, or any other telephone device that shares the same line as your DSL
A big factor is quality of the wiring. Older wiring was generally a 4 wires (Red, Green, Black and Yellow) in an insulator. This is ok for a single short run but Twisted Pair (UTP) is better. UTP of a rating of Cat-3 or Cat-5 should be used because the wire is twisted to cancel out noise and interference picked up from the air. Also you should use the line cord that comes with your DSL Device to plug directing in to your phone jack. Using telephone extention cords cause alot or problems. Test this by moving your equipment closer to the telephone jack.
Secondly, most commonly houses were wires in a manner where all the jacks in the house are in series, running from the phone box outside to the first jack in to the house and then to the next jack and so on. So this adds a lot of splices and places for noise to be introduced onto the telephone line. Try running a dedicated home run back to the main connect point for your house with UTP. You may have to temporarily unhook the wiring to the house to test these. If that clears up your problems, you may have to rewire all your jacks in your house.

A Third factor is having too many and/or low quality phones plugged into the same line. Try unplugging all the phones, fax, answering machines, etc in your house that are on the same line. Be sure to check for things that like TV Entertainment units (DirectTV, Sega Dreamcast) or utility meter reading devices that may be connected as well as alarm systems. The are known to cause trouble and are not something that people think about but still could use the same line.

What can I do to ensure clean house lines for my dsl connection?

The wiring inside your home or businness is your responsibility. Normally, your ISP will run wiring from the demarcation point( box where the phone wires are located within your building) to your pc. Make sure these wires are not close to fluorescent lights or devices that emit magnetic fields or high voltage.

What are the possible effects, if any, from using a 900 Mhz phone and DSL?

I attended a Cisco ADSL class that recommended not connecting cordless phones of any type close to the ADSL device. That may have been specific to the Cisco product (the instructor didn't specify), however, here is how he explained it.

The microfilters that most service providers issue are designed to filter out higher frequencies, thereby blocking the ADSL frequencies and not the voice frequencies. According to the instructor, quite a few of the cordless devices have the same sort of filters built into them to cut down on the interference that they place on the line. Good quality phones actually do a pretty good job. But some of the filters from cheap manufactures may actually have the reverse effect on your ADSL.

He demonstrated this by connected a cheap cordless phone directly to the back of a Cisco 677, and it immediately dropped train. After removing the cordless phone it trained right back up.

I would highly recommend that you connect your cordless phones in another area of the house to decrease the chance that it may cause problems.

In fact, any device that connects to the phone line (alarm systems, satellite dishes, game console systems, faxes and modems) have the potential to cause interference. If you suspect that there may be a problem, remove the device and see if your connection improves.

What can I do if I suspect something inside my house is causing DSL problems?

Typically a home has other equipment connected to the phone lines in the house. Phones, other computers modems, security systems and answering devices to name a few. Isolating these devices from the DSL line to your DSL modem, Router or other DSL service device is the only way to eliminate suspected attached equipment problems. Sometimes other equipment on the same line can "load" the line causing attenuation or even noise. This lowers signal strength and consequentially can interrupt DSL service. Typically Home Security systems are one of the most illusive problems to find. If you have one, start by disconnecting your Security System from the DSL line first. You might need to keep it off line for a few days while you evaluate your DSL response. If this does not cure your problem try removing each other piece of equipment from the DSL phone line, one at a time and noticing if removing it fixes your problems. Dont forget the DSL line filters and any extension wiring from the phone jacks as a potential problem also. Remember to plug the equipment back in before you unplug the next piece of equipment to check. This will help you locate load problems. If you find that removing one item makes your problem dissapear, this item may be the problem. Plug that item back in and see if your problem returns. If so, leave this piece of equipment connected and disconnect all other equipment on the line except your DSL modem or router. If your problem is still there, you have located the source of the trouble. This piece of equipment may operate fine by itself, but it is causing interference with your DSL line. You will need to remove it from your DSL service line. If your problem is not there, then you may be dealing with a line load problem. One option is to have your Telco come out and wire a new line inside your house and use a DSL splitter at the junction box outside your house. This will give you an isolated and dedicated line from the junction box outside to the input of the DSL line to your DSL equipment. Usually with new installs, you can have this done as "Reasonable" inside wiring by asking for it and is worth having done.

How can I get the best out of my inside wiring?

To get the best out of your inside wiring, make sure that there are no devices that might cause interference to the line. Remember, they are unsheilded copper wires. High voltage devices and speakers not sheilded will cause interference. (Speakers that came with your pc are sheilded so dont worry). Make sure connections to DSL jack are solid but do not overtighten. Overall, I wouldnt trust the install done by telco or clec. I had major packet loss, rewired my line from phone box to dsl jack, and everything is great now!!

How can I prepare my inside wiring for DSL installation?

The best thing you can do to prepare for DSL is to find out where your demarc is on the outside of your house/building, then determine where your modem is going to be inside. Then you will want to explore all possible paths between those two points that would be the shortest and easiest to run a wire. Try to route away from any kind of power wires or power using equipment inside. Disregard all the existing telephone wire, because you will want to run a new wire for the DSL line for optimum performance. The DSL installer will put a box called a CPE at the demarc which will act as a splitter to route the POTS line and the DSL line separately. If you have that extra wire, preferably Category 5 wire, the installer will be more likely to install a jack on the computer end for you. If you want to go ahead and install the jack yourself, you can get an RJ11 type jack at your local Radio Shack. If you use CAT 5 wire there will be 8 wires inside the insulation. These wires are color coded as a Blue wire with white dots and a White wire with blue dots for the first pair, which is all that you'll need. The rest of the wires are Orange/white, Green/white, and Brown/white. On regular house wire the colors are Red/Green and Yellow/Black. As I stated before all you need to hook up is the Blue/White pair of wires. On the demarc end of your wire all you need to do is coil up some extra wire so the DSL installer can hook up his/her end. On your end, if you hook up your own jack, you will need to connect the wire with the most BLUE to the RED screw in the jack and the wire with the most WHITE to the GREEN screw. In telephone language, the RED or BLUE wire is called the 'RING' wire and the GREEN or WHITE wire is called the 'TIP' wire. Be sure to mention tip and ring to the installer, he/she will be impressed.(haha) The most important part is to have that dedicated wire for your DSL connection so there will be no doubt that wiring is not a problem. Then you'll know if something goes wrong, it won't be your fault. Good Luck!

Are there alternatives to drilling holes in my walls to connect a 2nd computer?

Yes. There are wireless Access Points and Network Interface Cards that allow you to communicate at speeds of 11mbps. Signals run in the 2.4ghz range which will most likely not interfere with your DSL equipment like older 900mhz devices have been known to do.

How can I network my home without putting holes in walls (inexpensive method)?

A person can inexpensivly run cabling throughout their home without having to run the CAT 5 through the walls by purchasing a pvc channel (see your local home improvement store in the electrical section) for approximatly $3 per 7 foot section. This conduit comes in many different colors to help hide itself, it can also be painted to match the decor.

To install you can either screw (or nail) it in place, or you can use the adhesive tabs included with the conduit. The conduit is small enough to hide easily, yet, big enough to run 3 CAT 5 lines through.

This is a great alternative for someone living in an apartment, or for somebody who does not want to spend the money for a wireless kit (that will only give you at best 11 meg performance). The speed of your network is up to you and your equipment.

For the truly economy minded you can simply staple the CAT 5 cable along the baseboards. Be certain to use non-metalic, round-topped staples so that you do not crimp the CAT 5 or add inducted resistance (using metal staples) to it. You can run a CAT 5 cable up to 100 Meters without problem.

Can I run ADSL as a second phone line by installing one filter at the 66 bock?

Provided that you have voice service on your ADSL line, you can put a filter at the 66 block (or 110 block, or NID, whichever is your DMARC) instead of one at every station (phone) but you need to route unfiltered signal to the DSL modem. The only issue with this is that you need to pull a clean pair from before the filter to the DSL modem if you do not have a good quality unused internal pair.

As an example, at my house I have ADSL Service (really Paradyne MVL, but close enough for our purposes). The pair comes into a NID on the side of my house and from there goes to a 66 block in a closet. I have all my home station wiring pulled to the 66 block, which has a filter inline before it. From the NID, I have one other pair, which of course is unfiltered, all the way to the DSL modem.

Conventionally this separation is done via a "splitter" which gives better results but is more expensive and hard to find through conventional means. A splitter is normally installed at the NID and is a 3 port device. It splits the combined POTS+ADSL signal to POTS and DSL outputs. POTS output will be low pass filtered so high frequency DSL signal will not interefere voice and the DSL output will be high pass filtered (so voice signal will not interefe the DSL modem).

Swapping Inner and Outer Pairs on an RJ-11 Wall Plate

Some equipment requires a signal on the "outer pairs" instead of the "inner pairs" of an RJ-11 jack. You can use a line swapper or you can rewire your wall plate as shown. Note: If you rewire the wall plate as shown you will not be able to use any standard POTS devices that require the "inner pairs".

Schematic by Andy Houtz

Andy Houtz

How can I check if my inside telephone wiring is faulty?

First we must understand all the potential trouble points in the telephone system, and what problems can occur:
ItemWhat can go wrongWhere is it locatedWho fixes itLikelyhood this could be the problem
DSLAMBad firmware, faulty hardware, poor connections, needs to be resetCentral OfficeISPPossible
Line cardFaulty hardware, poor connectionsCentral OfficePhone CompanyNot likely
Wiring from the DSLAM to your homeCracked wiring, wet wiring, too close to electricalwiresBetween the central office and your homePhone CompanyLikely
Demarcation block (demarc)Full of moisture, corroded connections, loose wiringOn the side of your home or in the basementPhone Company*Not likely
Inside wiringCracked wiring, wet wiring, too close to electricalwiresBetween the demarc and the phone jack(s)Property OwnerLikely
Wall jackPoor connections due to abuse, dirt, or painting over the jackIn your homeProperty OwnerPossible
Phone cordcracked or damaged wiring, cord too long, broken end connectorsBetween the wall jack and your modemCompute OwnerLikely
DSL ModemFaulty hardwareOn your deskComputer Owner**Possible
Ethernet cablecracked or damaged wiring, broken end connectorsBetween the modem and your network cardComputer OwnerPossible
Network Card (NIC)Faulty hardwareIn your computerComputer OwnerPossible
Upgrading the phone lines inside your house may certainly help. But as you can see above, there are other things that could be at fault. So, before you put out a pile of money to have that work done, try connecting your modem directly to the demarcation point to verify if your inside wiring is to blame.

What is the demarcation point? The demarcation point (or demarc for short) is a small box on your phone line that defines the end of Bell's responsibility and the start of your responsibility for repair and maintenance of telephone wiring. The demarc is usually located on the outside of your house, although on some old houses it may be located inside. If you cannot find your demarc at all, contact your telephone company and either have them find it or install one. The maintenance of the demarc is generally the responsibility of the phone company.

There are several different styles of demarcs. They come in different shapes, sizes, colors, and the internal connectors can be different, but the function is the same. Usually there will be markings on the outside to identify it as a demarc - the phone company logo, or simply words relating to telephone or the abbreviation NID = network interface device - a fancy name for a demarc.

So once you've located the demarc, go ahead and open it. It may just pop open with a small screwdriver or even your bare hands. There also may be a screw that needs to be turned or removed to gain access to the inside of the box. If the demarc is inside, there may not be a box around it at all; you can identify it by looking for a block with some screw terminals with red and green wires connected to it.

NOTE: Telephone wiring is low voltage and unless you are standing in water holding both red and green lines when the phone rings, the risk of shock is very low. You should still take every precaution when working with any electrical wires, and if you are not comfortable working with phone lines, please consult either your phone company or a qualified professional.

There are two types of demarcs generally in use.

The first type is the older one, about the size of a deck of playing cards. This demarc contains only screw terminals inside. If this is the demarc you have, you will need to obtain a baseboard phone jack and a short piece of wire to temporarily connect your modem to. You can get a baseboard jack at Home Depot or Radio Shack. When you open the baseboard jack, you will see some red and green wires. You will also see some red and green wires inside the demarc. Connect red to red, and green to green. Connect a telephone to see if you get a dialtone (don't forget the DSL filter!) Disconnect the red and green wires that go into your home. You will have to reconnect these later when you're done.

The second type of demarc is much larger, about the size of a box of crackers. This one is much nicer than the screw terminals because it has standard phone jacks inside to allow you to quickly disconnect your home wiring from the telephone company wiring, and connect a telephone device directly to the demarc. If this is the demarc you have, you will not need to do any wiring. Just disconnect the phone jack, and plug your modem right in there with no DSL filter. Obviously you will not have telephone service once that jack is disconnected, but this won't take long.

Once you have your modem connected directly to the demarc, you will need to connect it to your computer. The best way to do this is to either move the computer in the house so it is as close to the demarc as possible. If you have a laptop, you can just take it outside. Or purchase a long ethernet cable and run it through your house temporarily. Do not use a telephone extension cord for this exercise; use as short of a phone cord as possible. You may even want to try a couple of short phone cords in case one of them is faulty.

Now, run some speedtests. A good speedtest is to download a large file from your provider's homepage, or Microsoft since those pages tend to deliver top speeds. You can also run some speed tests from this site. If your speed tests improve, then you know your inside wiring is to blame and is in need of replacement or repair.

9. Tricky Applications

What is another way to repair IE if it doesn't appear in the Add/Remove programs

If Internet Explorer does not appear in the Add/Remove Programs box in the Control Panel (because you have no backup IE) there is another easy way to access the repair tool. Go to Start, Programs, Accessories and, on the drop down menu, click on System Tools and, finally, on System Information. On the System Information window, click on Tools and in the drop down box click on Internet Explorer Repair Tool.

For Windows XP users (thanks to djdanska)
Here are two ways to reinstall Windows IE for Win XP:
1. The only way to repair Internet Explorer is to have sfc check the system files by clicking on the Start Menu, then Run, and type in:
sfc /scannow
and then click on OK.

2. Another way (which has worked for me):
# Start the Registry Editor
# Go to HKEY_LOCAL_MACHINE \ SOFTWARE \ Microsoft \ Active Setup \ Installed Components \ {89820200-ECBD-11cf-8B85-00AA005B4383}
# right-click the IsInstalled value, and then click Modify
# Change the value data, from 1 to 0
# Close the registry editor
# Download and install Internet Explorer 6.

The above will let you reinstall the Internet Explorer 6 browser component. To reinstall Outlook Express 6, change the IsInstalled value from the following registry key: HKEY_LOCAL_MACHINE \ SOFTWARE \ Microsoft \ Active Setup \ Installed Components \ {44BBA840-CC51-11CF-AAFA-00AA00B6015C}

How can I shut down/restart my computer remotely?

To shutdown or restart your machine remotely- Create a file called "RemoteShutdown.js" consisting of the following single line:


Save it on your desktop or anywhere else convenient. When you want to shut down your machine remotely, click the file and select your desired option (shut down or restart). I keep a shortcut on my quick launch menu on the taskbar.

For an in-depth description of how to perform this task with Windows 2000, see this MS Knowledge Base article:;en-us;Q317371

Using Dialpad for a phone,they can hear me but I can't hear them.

Check the dialpad FAQ on configuration of dialpad with private networks. They answer the question quite clearly, indicating the ports you must open on your NAT or firewall device, and offer step by step instructions for many popular firewall/NAT solutions.

I am having trouble with Windows 98ICS and directplay games

There has been some discussion that Windows 98ICS cannot host certain programs on client machines, they must only be run on the ICS host. [more to be added].

Some users (not all) are unable to use my FTP server

FTP defaults to active mode. Active mode FTP is not compatible with regular NAT setups, in that case, passive mode FTP must be used. FTP as presented in a browser defaults to passive, but an FTP client will allow selection of active vs passive. If selecting passive mode makes the FTP hangs or failures disappear, the problem is almost certainly NAT related.

I cannot use certain IRC functions, like DCC send.

Again, this is the result of using NAT. NAT must be configured carefully to allow all functions of IRC to work properly, or for ICQ inbound messages to work. Check one of the NAT sites in Sites page for more information.

My game/directplay does not work over NAT!

If your game uses microsoft DIRECTPLAY (directX), and if you have a Netopia, Linksys, or other NAT device, then you need to configure it for directplay because by default it will now work.
Directplay is microsoft directX protocol for multiplayer games, and it isnt NAT friendly!
Nevertheless, this link might help:
» ··· 78op.htm
It describes the port ranges you need to MAP to your interal PC for incoming connections. Refer to your NAT device documentation for how to map incoming port ranges to a single internal IP address.
If you have a NETOPIA, ensure you are uptodate on firmware, since that allows specification of mapping of NAT port range from outside, to a machine on the inside.

Edit to add: some of the above is outdated info. Here is current info:

DirectPlay 8 and above are NAT friendly with UPnP devices. Prior to DirectX8, you had to manually forward ports.

Here's a link: »

Using Windows ICS causes slowdown

Check in your registry for the key

HKEY_LOCAL_MACHINE/system/current control set/services/icshare/settings/general/internetmtu

If this key is set to 512 or a low number, change to match your external MTU, for example 1492 for non PPPoE connections!
Please also check Tweaks information pages, and DrTCP (available from those pages).

How can I use DSL with NetMeeting or Intel Video Phone?

NetMeeting and Intel Video Phone (and other Video user to user applications) use a protocol that is not NAT friendly.
If your connection is over a modem, you've probably not had any problem using video software. If you are getting a DSL line, and going to use NAT to share the connection amongst other PCs in your house, or are provided equipment setup for NAT, then you will find that your video software will not work, or will only partially work.
There are currently a few work-arounds to this:
•Request a bridged connection, where your IP address on the PC is a public one.
•Use Sygate as NAT software. This would be installed on your "gateway" PC, with a public IP address, and Sygate would be responsible for implementing the sharing solution. (again, avoid any hardware NAT solution).
•Place the PC you want to use NetMeeting from in the DMZ port of your NAT box, if it has one.
•Investigate if your NAT box (or DSL modem or router) firmware has a new release now offers support for Net Meeting or other video software.. upgrade to that.
•Use Linux and ipchains as your gateway machine, and the appropriate plugin module to support Net Meeting over NAT.
There are no other solutions currently.

What are Host Headers

Host Headers allow a web server to host more that one website domain over a single IP address. This is made possible by new generation browsers which add an additional header to the HTTP request which specifies the domain being requested, in addition to the IP address. The Web Server can then interperate this header and direct the HTTP request to the correct website.

How do I set up host headers in IIS 4.0

1. Add your DNS entry to your DNS server and point it to your server IP address. Do this for each domain you are using, pointing each one to the same IP address.

2. In the IIS console, right click on the website you want to add host headers too, then choose Properties from the drop-down lost. Click on the website tab, then choose advanced. Enter the domain name, port and IP address you want to use for this website.

How can I improve the performance of my web server?

Improving the perfromance of a web server is a continuos process of refinemnt.

In a nutshell a web site is only as fast as the first bottleneck you encounter will let it be. A bottleneck can be as simple as a setting in the registry or in whatever web server software you are using, or it can be disk IO, lack of RAM, general speed of the processor/RAM?system bus combination or, as most people find from an end-user point of view the bandwidth of a connection.

The trick is to find the first bottleneck. Resolve the issue and then find the next and so on until it performs well enough for your liking. You can always make it run better, but perfomance gains are usually smaller once you've reached a certainlevel. (e.g. a supercomputer on a 100Mbit+ connection that is tuned ever so well :)

If you have the funds employing a Managed Service Provider (MSP) like iSharp wil enable you to performance test your site and isolate these bottlenecks as well as suggest possible solutions for you to consider. I am an employee of this company so of course I am biased, but we have competetors that you can investigate as well, or you can invest a lot of money and time and buy a tool like Silk, Load Runner etc and do it yourself. At any rate you need a benchmarking tool of some sort that can produce load on the site to be able to consistently expose your site's bottlenecks.

How do I repair IE when it doesn't appear in the add/remove box?

If the Internet Explorer Repair Tool Verification does not work, or if Internet Explorer is not listed in the Add/Remove Programs tool in Control Panel, you may be able to reinstall or repair from this link:


I can connect with Enternet 300 in Windows 2000, but my browser won't work.

This is a bug in the TCP/IP programming in Enternet 300 version 1.34-1.41c. If you have Enternet 300 v1.34, you can double-click on Enternet 300, go to Connections-Settings-Advanced, and change Private API to DHCP. This will fix most problems for 1.34 If you have Enternet 300 v1.4-1.41c, you will have to upgrade to Enternet 300 v1.5 or higher, install RasPPPOE, or downgrade to Enternet 300 v1.34 and change Private API to DHCP.

Here is a excerpt from the Enternet 300 v1.5a Release Notes(file is in pdf.format):


Workaround for Microsoft TCP/IP address setting problem with W2K. The workaround fixes a problem occurring with some Windows 2000 systems whose browsers are unable to browse correctly upon connection. Note that thre is also a problem with the Windows 2000 in general which requires service pack 1 for resolution. In all cases, we recommend that you install service pack 1 before installing Enternet 300 v1.5a for Windows.

Enternet FAQ #9 at the Efficient Networks website about connecting and not browsing with W2K.

How do I remove NetBIOS from TCP/IP or DUN connections?

The Network Basic Input/Output System (NetBIOS) is a session layer communications service used by client and server applications in IBM token ring and PC LAN networks.
NetBIOS provides applications with a programming interface for sharing services and information across a variety of lower-layer network protocols, including IP.

By closing or disabling NetBIOS when you don't use it, you can have increased security and possibly increased transfer speed. This fix only applies to users that have a connection established through dial-up or broadband. Make sure you are NOT already using the NetBIOS (Network Basic Input/Output System) protocol or a network/LAN/WAN/peer-to-peer/etc hookup, or this will seriously impair your connection.

1. Go to Start, Settings then open up the Control Panel.

2. Double-click to open the Network applet. Find all the entries that have "TCP/IP -> besides the name(ex. "TCP/IP -> Dial-Up Adapter").

3. Highlight and click on "Properties" and go to the tab called 'Bindings'. Un-bind or de-select everything in the list, and select 'NO' if it asks you if you want to bind anything. Repeat for any other TCP/IP adapters.

4. When done, reboot your computer. NetBIOS port should be closed on the internet. You can make sure it is closed by going to the "NetBIOS" tab, and the NetBIOS option should be un-ticked in your TCP/IP adapter properties.

DCC Send settings in mIRC IRC client

We address that problem in our mIRC IRC client set up section.

Open mIRC and go to File->Options->Connect->Local Info.

There, change the Lookup Method to Server. Press OK, close mIRC and restart it.

This is also valid for any other IRC client, such as PIRCH. The Local Info setting cannot be "Local Host" when using a DSL connection.

How do I use Linksys routers with web servers?

Linksys routers are Probably the best routers to handle this type of application.
    • Enter in IE. (or what you have set it to)
    • Click advanced -> forwarding.
    • Enter the port range, 79-81 for web servers.
    • Enter the IP for the web server.
    • Save settings.
    • Enjoy your web server!

HOW TO: Use the Remote Shutdown Tool in Windows 2000

Microsoft Knowledge Base Article - 317371

HOW TO: Use the Remote Shutdown Tool to Shut Down and Restart a Computer in Windows 2000

The information in this article applies to:
Microsoft Windows 2000 Server
Microsoft Windows 2000 Advanced Server
Microsoft Windows 2000 Professional

This article was previously published under Q317371

Description of the Shutdown.exe Tool
This article describes how to use the Remote Shutdown tool (Shutdown.exe) to shut down and restart a local or remote Windows 2000-based or Microsoft Windows NT 4.0-based computer.

Shutdown.exe is available in the Microsoft Windows 2000 Resource Kit. It is a command-line tool that you can use to shut down or restart a local or remote computer that is running Windows 2000 or Windows NT 4.0. If you want to schedule a computer to shut down and restart at a specific time, use Shutdown.exe in combination with the at command or Task Scheduler.

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Description of the Shutdown.exe Tool
Shutdown.exe uses the following syntax:
shutdown \\computername /l /a /r /t:xx "msg" /y /c

You can use the following switches with Shutdown.exe:
\\computername: Use this switch to specify the remote computer to shut down. If you omit this parameter, the local computer name is used.
/l (Note that this is a lowercase "L" character): Use this switch to shut down the local computer
/a: Use this switch to quit a shutdown operation. You can do this only during the time-out period. If you use this switch, all other parameters are ignored.
/r: Use this switch to restart the computer instead of fully shutting it down.
/t:xx: Use this switch to specify the time (in seconds) after which the computer is shut down. The default is 20 seconds.
"msg": Use this switch to specify a message during the shutdown process. The maximum number of characters that the message can contain is 127.
/y: Use this switch to force a "yes" answer to all queries from the computer.
/c: Use this switch quit all running programs. If you use this switch, Windows forces all programs that are running to quit. The option to save any data that may have changed is ignored. This can result in data loss in any programs for which data is not previously saved.
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To shut down the local computer in two minutes and display a "The computer is shutting down" message, use the following line in a batch file or type it at a command prompt, and then press ENTER:
shutdown /l /t:120 "The computer is shutting down" /y /c

To cancel the shutdown process, type the following line at the command prompt, and then press ENTER:
shutdown /l /a /y

To shut down and restart a remote computer named "Support," use the following line in a batch file or type it at a command prompt, and then press ENTER:
shutdown \\support /r

To schedule the local computer to shutdown and restart at 10:00 P.M., type the following line at a command prompt, and then press ENTER:
at 22:00 shutdown /l /r /y /c

To schedule the local computer to shutdown and restart at 6:00 P.M. every weekday, type the following line at a command prompt, and then press ENTER:
at 18:00 /every:M,T,W,Th,F shutdown /l /r /y /c

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The specified computer may not shut down when you use the Shutdown.exe tool to shut it down. This behavior can occur if the Unlock Computer dialog box appears on the desktop, or if the computer is locked. For additional information about how to resolve this issue, click the article numbers below to view the articles in the Microsoft Knowledge Base:
307635 Remote Shutdown Results in Logoff When Unlock Computer Dialog Box Is Displayed

288180 The ExitWindowsEx() Function May Not Log Off the User or Shut Down the Computer If the Computer is Locked

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For more information about Shutdown.exe, type shutdown /? at the command prompt, and then press ENTER.

For additional information about how to use the AT command to schedule tasks in Windows 2000, click the article number below to view the article in the Microsoft Knowledge Base:
313565 HOW TO: Use the AT Command to Schedule Tasks

For additional information about how to use Task Scheduler to schedule a task in Windows 2000, click the article number below to view the article in the Microsoft Knowledge Base:
300160 HOW TO: Schedule a Server Process in Windows 2000

For more information about the Windows 2000 Resource Kit, visit the following Microsoft Web site:
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Can I use two DSL modems on the same line?

No. It is not possible for two modems to sync at once on the same line. If you want to connect more than one computer to your DSL connection, you must create a home network.