dslreports logo
site
 
    All Forums Hot Topics Gallery
spc

spacer




how-to block ads


Search Topic:
uniqs
18668
share rss forum feed

cramer
Premium
join:2007-04-10
Raleigh, NC
kudos:8
reply to BiggA

Re: Analog Voice Gateways

It's supposed to be -- modern systems should follow the 802.3xx standards. If you're doing a voice/data vlan setup, and data isn't on a non-tagged vlan, then it doesn't work out so well.

I'm tired of debating best practices, and disaster recovery theories.
The cost of stringing two loops vs. just one, is very cheap insurrance against a great many problems and possible futures. When you're walking into an existing structure, you make do with what's there. If you have a blank canvas, you'd be a fool to paint yourself into such a corner just to save a few dollars upfront.


cramer
Premium
join:2007-04-10
Raleigh, NC
kudos:8
reply to tubbynet

in a small office, yes. however, i've done a lot of work the past two years in medical acute care facilities...

You're rebuilding your house four times a year and you want to complain about the cost of the plumbing??? Here, they're creating a massive problem that should never be. I guess their cube walls don't have modular data cabling to match the modular power distribution.

(take a page from Vegas... a raised floor allows for redesigned layouts at substantially reduced costs. For Vegas, it complicates security a wee bit, but that's a small price for not having to jackhammer and re-pour floors to move cable runs.)

[edit: I recall a company making modular cube flooring to carry data and power. Makes this sort of situation a non-problem.]

no. poe switches will be more expensive because they provide additional features that regular switches don't.

Manufacturers charge much more for integrated PoE switches because they know people will pay it. (simple economics.) Yes, there's more in there, but certainly not *thousands* more. If I can buy new midspan modules for hundreds, why is the same technology built into the switch suddenly worth 10x as much? 50% off is still 50% screwed over.


battleop

join:2005-09-28
00000
reply to BiggA

Yes.



battleop

join:2005-09-28
00000
reply to cramer

On the new build outs I always tell my customers to drop to cables per user. Even if they don't terminate the second at least get the cable there for future use.

In a retro deployment 99.999% of the time the customer isn't going to pay for the second drop unless it's absolutely needed. To be honest I don't blame them.



battleop

join:2005-09-28
00000
reply to BiggA

I've got an upcoming deployment were I am going to use 5 IAD-2431-24FXS and a dozen IP phones. Even though I have the owner running 2 Cat5e to each room there is absolutely no need for IP phones in each room.

There are some situations where IP phones are not just needed. I suspect that he also has a similar situation.



Edrick
I aspire to tell the story of a lifetime
Premium
join:2004-09-11
Woburn, MA
reply to jmich

Everyone sees different things, all the VoIP setups I've seen have segmented the phones from the data, when it comes to having the availability to do so. Obviously some cases there's existing cable and that's not possible.



TomS_
Git-r-done
Premium,MVM
join:2002-07-19
London, UK
kudos:5
reply to jmich

Why burn twice as many switch ports when you dont have to?

Switch ports may be cheaper than router ports, but they still have a cost, and youre only trying to save yourself from a situation that *might* be a problem which if it does occur can be rectified easily enough.

:-P


BiggA

join:2005-11-23
EARTH

Good point. You may as well use the phone hardware you're paying for.



blohner

join:2002-06-26
Cortlandt Manor, NY
Reviews:
·ooma
·Google Voice
·Optimum Online
reply to jmich

I see no reason to separate voice from data in a lot of instances: It simply doubles the risk of network failure: In most cube settings how can someone do a job with a phone if the network is down? I certainly couldn't... (Give me a network only and I am 80% productive. Give me a phone only and I am 0% productive)....
--
I am addicted to speed --- Boost + speed that is ---



Edrick
I aspire to tell the story of a lifetime
Premium
join:2004-09-11
Woburn, MA

said by blohner:

I see no reason to separate voice from data in a lot of instances: It simply doubles the risk of network failure: In most cube settings how can someone do a job with a phone if the network is down? I certainly couldn't... (Give me a network only and I am 80% productive. Give me a phone only and I am 0% productive)....

How does it double the risk of failure? If your phone network goes down you at least still have data, if your data network goes down you at least still have phone.
--
Edrick Smith
Independent Film & Broadcast Producer
»edricksmith.com

Hahausuck
Premium
join:2003-12-14
kudos:2
reply to BiggA

said by BiggA:

Isn't the PoE switch auto-sensing so that they could safely plug the line going to the phone into the back of the PC if the phone went south?

Yes, by 802.3af standards the PSE will detect if the device connected to it is able to be powered via a resistance value.

Power is not shot down the pairs until this is verified, so you can have PD and Non-PD on the switch.

Being in the correct VLAN is a different subject all together, so you'd still have a problem.
--
"Saying something in another language that you don't think the other person understands is just saying that you're a pussy and are too afraid to say it in English." --Harddrive

BiggA

join:2005-11-23
EARTH

Or you could just keep them on the same network... Just like home users using VOIP do.



Edrick
I aspire to tell the story of a lifetime
Premium
join:2004-09-11
Woburn, MA

said by BiggA:

Or you could just keep them on the same network... Just like home users using VOIP do.

Personally I don't care about them being on the same network, I just prefer them to be on a separate port. Now I work with clients in the Media Production end of things. So they're always using gigabit and specialty setups, worried about segmenting their network, etc...
--
Edrick Smith
Independent Film & Broadcast Producer
»edricksmith.com

cramer
Premium
join:2007-04-10
Raleigh, NC
kudos:8
reply to BiggA

Tell it to the Vonage crowd. Despite the thing being upstream of their router where it can "apply QoS", people still have call quality issues if the line is moderately used. VoIP within a company LAN, you'd think that wouldn't be a problem, but it can, and does, happen.

In the end, there are as any reasons to keep voice and data as isolated from each other as possible, as there are not to. The best way to learn is having them sneak up and bite you on the a**.

(I see it myself with VoIP over IPSec. Back when TWC was 384k up, you best not do anything while using the phone. Now at 1M up, you just have to be careful not to push it while on the phone. Unless you like a stuttering phone.)


BiggA

join:2005-11-23
EARTH

On a 100mbit line, it's unlikely to happen. I don't seem to have issues with my AT&T Microcell when I'm hitting the 'net hard, probably because I have the Microcell god-esque QoS priority in the router.

I do have general upload jamming issues though, so I've cut my torrents, backup, and Google Music down to 1mbps each, but if two or three of them kick on at the same time, or with Dropbox, then everything kind of grinds to a halt on the web browsing side of things.


sk1939
Premium
join:2010-10-23
Mclean, VA
kudos:10
Reviews:
·T-Mobile US
·Verizon FiOS

1 edit

It's not a question of bandwidth to the internet for many of these campuses, it has to do with QoS and congestion on the internal network. Additionally, the number of lines many of these enterprises have would take a heavy toll in bandwidth (they number in the hundreds, if not thousands). Remember that the average VoIP call takes about 130kbps of bandwidth (counting overhead), or about 80 lines with 10mbps of bandwidth.

I'll give my two cents having designed a network for a higher education campus.

Due to security issues, and the existence of an original PBX, only some lines were replaced with VoIP, notably offices and labs. Classrooms and Emergency phones remained on the PBX due to technology limitations and cost. Each of the VoIP phones needed a new line to be run for every phone since the existing wiring was based off of Cat 3. The network was designed so that voice traffic was independent of the data network to help with latency, security, and network congestion issues. Likewise, the IP cameras on campus are also on an entirely separate network for security reasons. This particular organization uses PoE for the switches at quite an expense, and runs an Avanya PBX system for VoIP, and a Siemens PBX for POTS.

The POTS infrastructure was not transitioned using FXS devices for the simple reason that the existing PBX was in place, and for emergency situations should the core routers fail, the campus would still be able to reach out through conventional means.

The problem with VoIP is that it requires you to have a stable, consistent, and good quality internet connection with little loss. Should your internet connection fail at any time, then you have serious issues about not being able to contact the outside world. "Use your cell phones" is not an acceptable answer to these enterprises.


BiggA

join:2005-11-23
EARTH

Why are the bitrates cranked up so high? Cell phones are something like 10kbps.

"Use your cell phones" should be an OK answer, as they will always work. Of course, you could always have a backup internet connection in case one fails...


sk1939
Premium
join:2010-10-23
Mclean, VA
kudos:10
Reviews:
·T-Mobile US
·Verizon FiOS

1 recommendation

Standard VoIP bitrates (like G.711) are at least 40kbps, and many are 50 or 64 plus packet overhead. These are land lines that have to be clear to the other end. There's a reason Verizon ran those "can you hear me now?" ads, since 10kbps is terrible quality considering AM radio is 24kbps.

It will never be acceptable to Fortune 1000 companies, especially when people/clients go to call them. Additionally, if you add that much cell traffic, the towers can be overloaded, not to mention the cost of minutes. It just has to work, because that's what you are paid to do. Yes, you always have a backup but even backups fail.


BiggA

join:2005-11-23
EARTH

Regular phone systems can bite the dust too, it's not like any of this stuff is super reliable. At least VOIP you could have multiple bandwidth providers as redundancy, as opposed to one phone company where if something blows up.

It's hard to find hard data, but AFAIK, the highest bitrate WCDMA can handle is 23kbps, and WCDMA on the iPhone is higher than landline quality. Admittedly, there's probably a lot of processing going on in the iPhone, but it is able to pull it off.

Not sure if I've ever used a VOIP system, but a good cell phone connection (like AT&T 3G on the iPhone 4S) definitely sounds better than a copper landline. Again, might be processing and massaging, since Apple spends a LOT of time and money on every detail of the thing.


sk1939
Premium
join:2010-10-23
Mclean, VA
kudos:10
Reviews:
·T-Mobile US
·Verizon FiOS

POTS is still more reliable than cell phone service that's for sure. The problem with redundancy I already stated before. I've also previously stated the reason companies keep POTS, mostly due to security and cost.

Higher than land line quality perhaps, but not better than VoIP. Additionally quality is not important in classrooms and for emergencies.

That's subjective and depends on the quality of the line, the distance, the age of the line, the phone handset, and variety of other factors.


BiggA

join:2005-11-23
EARTH

OK, maybe VOIP can beat a cell phone, I know Skype has some of the best quality that you'll get on any sort of "phone". Land lines aren't that great, however, as they are analog and have basically no processing power at the end of the line. The best calls that I have are AT&T to AT&T on the cell phone side...


BiggA

join:2005-11-23
EARTH
reply to sk1939

Also, why would you have phones in the classrooms? There is no reason to have them, since people are moving in and out of them all the time. My university has the same thing, and it's just a waste of money. As are dorm phone lines, since no one uses them. They should just rip the whole system out.


sk1939
Premium
join:2010-10-23
Mclean, VA
kudos:10
Reviews:
·T-Mobile US
·Verizon FiOS

The phones are there for emergencies, and for the instructor to call for services such as Plant Ops, Security, A/V, etc.

Dorm phones are a legacy from the time before cell phones. Why would you rip out a perfectly functional system that's in place?


BiggA

join:2005-11-23
EARTH

I've literally seen professors need to make phone calls, they don't even notice they are there. They just pick up their cell phones anyways. If they put that money towards getting better in-building cell coverage, we would all benefit.

Well, maybe not rip out, but just unplug and let it go dead. There's no reason to keep paying every month to support a system that no one uses.



Edrick
I aspire to tell the story of a lifetime
Premium
join:2004-09-11
Woburn, MA

I'm guessing you're still in college? I myself only just recently graduated two years ago. However plenty of times in real world situations campuses, companies, government etc... require things to be secured, segmented, installed and maintained even if you don't view them as needed. From the world experience I've had so far what sk1939 has said is completely accurate.

Also an example public schools are required to have some type of hardwire communication in the classroom for the teachers to call to the office. I've seen the hardwired phones used many many times in the two universities I've attended to contact plant staff, call for an emergency or other on campus calls. Why have the teacher be required to save 20 phone numbers into their cell phone when they can just use the phone system in the school and call a local extension.
--
Edrick Smith
Independent Film & Broadcast Producer
»edricksmith.com


kc8jwt

join:2005-10-27
Syracuse, OH

Edrick is right. I work in a public school and we have a copper plant for phone and our network plants.

Our phone system is a traditional PBX with a VoIP card to call other districts in our consortium. In each classroom we are required to maintain a phone jack, two network drops, and a CATV jack. If we don't maintain them, we can not get money from a state grant designed to maintain them.

The problem we have with it is that AT&T put the jacks in illogical locations such as the back of the room when the teacher's desk is at the front of the room.


BiggA

join:2005-11-23
EARTH
reply to Edrick

I'm talking higher ed. K-12 makes sense, as the teachers need to be able to communicate with each other, support staff, and the office.

In higher ed, no one would know the numbers anyways unless they are printed somewhere (just as easy to dial on cell), or they Google them and dial them, which would be on their own smartphone anyways.



Edrick
I aspire to tell the story of a lifetime
Premium
join:2004-09-11
Woburn, MA

1 recommendation

said by BiggA:

I'm talking higher ed. K-12 makes sense, as the teachers need to be able to communicate with each other, support staff, and the office.

In higher ed, no one would know the numbers anyways unless they are printed somewhere (just as easy to dial on cell), or they Google them and dial them, which would be on their own smartphone anyways.

It's still far easier to have hardwire, I know plenty of spaces on both campuses where we didn't have cell service or the teacher didn't have a phone, perhaps the computer network was down and they cant get on the intranet. They can pickup and hit 0 be connected to the switchboard.

Alls I'm saying is hardwire is far from dead and will be around for quite sometime.
--
Edrick Smith
Independent Film & Broadcast Producer
»edricksmith.com

BiggA

join:2005-11-23
EARTH

No one uses them. No one wants them. If there's not good cell service, then that's a legitimate issue that needs to be dealt with, either through repeaters or partnering with AT&T and Verizon to come in and install sites to cover deep inside buildings.



Edrick
I aspire to tell the story of a lifetime
Premium
join:2004-09-11
Woburn, MA

1 recommendation

said by BiggA:

No one uses them. No one wants them. If there's not good cell service, then that's a legitimate issue that needs to be dealt with, either through repeaters or partnering with AT&T and Verizon to come in and install sites to cover deep inside buildings.

Well with an attitude like that I don't know how well you'll do in the industry. Cause lots of people use them and lots of people still want them. This installation posted by the OP is a prime example, if no one used them or wanted them why would the university spend all the money?

Cell service is not a valid replacement, wether it be local, state or government requirements or just the institutions requirement. A cell network goes down, especially during emergencies.

What practical experiences do you have where you can make a statement that no one uses it no one wants it other than your personal experience at your campus?

Just like Antenna you might say who the hell would use antenna for TV, lots of people still do.
--
Edrick Smith
Independent Film & Broadcast Producer
»edricksmith.com