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Forum1. General Questions
2. Forum Links
3. Troubleshooting4. Fiber Optic Service Providers4.1 Level 3
4.3 SwitchPoint
5. T-1 Connections
6. T-3 Connections7. Optical CarriersForum got feedback?by redxii got feedback?by redxii 1. General Questions
 If you look closely at a single optical fiber, you will see that it has the following parts: Hundreds or thousands of these optical fibers are arranged in bundles in optical cables. The bundles are protected by the cable's outer covering, called a jacket. Optical fibers come in two types: Single-mode fibers - Used to transmit one signal per fiber (used in telephones and cable TV) Multi-mode fibers - Used to transmit many signals per fiber (used in computer networks, local area networks) Some optical fibers can be made from plastic. These fibers have a large core (0.04 inches or 1 mm diameter) and transmit visible red light (wavelength = 650 nm) from LEDs. "How Fiber Optics Work", HowStuffWorks (»www.howstuffworks.com), by Craig C. Freudenrich, Ph.D. HowStuffWorks, Inc., 2002.
got feedback?fiber lengths can be used as voltage or temperature sensor.
Pl Visit the link:
http://www.fiberopticinstrument.com/papers/pdf/Fiber%20optic%20intrinsic%20voltage%20sensor.pdf 2010-03-24 00:26:39 (santanu by redxii Because of these advantages, you see fiber optics in many industries, most notably telecommunications and computer networks. Source/Reference
got feedback?why do I feel sick passing under the newly installed fiber optics cable in my neighborhood? 2009-11-03 22:28:47 * fibers are minimum EMI/EMC corrupted.
* Different FOS and in fiber communication devices are possible with mm/sm fiber.
For more Details about in fiber amplifier follow the link:
http://www.fiberopticinstrument.com/papers/pdf/RTEE-10-A23.pdf 2010-03-23 22:35:05 by redxii Thanks to: Lanik got feedback?I don't know if this is old information, or if it's based on having work done by a commercial contractor or what, but it seems extremely out of date considering you can buy a 100 meter roll of dual multimode fiber with preattached LC connectors for under $100 on eBay, and we just picked up two brand new media converters with the LC modules for $115 apiece. Considering that copper is going up in price and simply doesn't work well on runs that even approach the theoretical 100 meter maximum (particularly buried underground runs, and more particularly after there has been a nearby lightning strike), I would say that it may be cheaper in the long run to just run fiber than Cat 5e underground, unless one lives in a place where lightning never strikes. In any case, unless I'm missing something here, the "low six figures for 100 feet" is ludicrous beyond belief!
Perhaps there is a need for a separate FAQ for home/SOHO fiber. Just as 10Base-T and 100BaseT wired networks are considerably different from DSL (even though both use copper wires), using fiber to connect a couple of nearby buildings is far different from a 50 mile commercial fiber circuit. And believe me, there is not nearly enough information out there for do-it-yourselfers that are trying to do their first fiber run - I'd love to find even ONE good page on the subject. 2009-08-19 05:14:26 by redxii "Fiber to the Curb" (FTTC) refers to the installation and use of optical fiber cable directly to the curbs near homes or any business environment as a replacement for "plain old telephone service" (POTS) Fiber to the curb implies that coaxial cable or another medium might carry the signals the very short distance between the curb and the user inside the home or business. "Fiber to the Home" (FTTH) is a network technology that deploys fiber optic cable directly to the home or business to deliver voice, video and data services. By leveraging the extremely high bandwidth capacity of fiber, FTTH can deliver more bandwidth capacity than competing copper-based technologies such as twisted pair, HFC and xDSL. Fiber to the home is deployed in two primary architectures - point-to-point and passive optical network (PON). While both have their place in solving the last-mile bottleneck, a point-to-point architecture is generally deployed to businesses in metro and urban areas, while a PON is a more cost-effective solution for small- to medium-sized businesses and residences. A PON architecture allows a single fiber from the central office (CO) or headend to be split up to 32 ways, delivering high-bandwidth converged services to multiple residences or businesses, using a single optical transceiver in the CO. In a point-to-point configuration, an optical transceiver for each subscriber is required in the CO, thus substantially increasing the total cost of deployment. "Fiber to the neighborhood" (FTTN) refers to installing it generally to all curbs or buildings in a neighborhood. Hybrid Fiber Coax (HFC) is an example of a distribution concept in which optical fiber is used as the backbone medium in a given environment and coaxial cable is used between the backbone and individual users (such as those in a small corporation or a college environment). Source/Reference (2)
got feedback?by redxii DFITL is in short adsl over FITL (fiber in to loop/fiber to the curb). The way it works is it sends the dsl signal over fiber to the ONU thur the DISCS system and connects to the ATM in the CO. The card in the ONU acts like the DSLAM since the signal runs over copper from the ONU to the house. by fiber_man IFITL is an implementation of FTTC by Marconi Communications which delivers integrated voice, Digital TV, and high-speed data (PCDATA). PCDATA which is simply 10Mbps Ethernet delivered to your doorstep. You can't buy "PCDATA" itself because there are no tarrifs for that class of service. Instead Bellsouth sells a throttled version (1.5Mbps down/ 256Kbps up) of PCDATA as "Fast Access". Some call this "DSL over Fiber", but this is a misnomer as there is no DSL signalling involved at all...it's Ethernet, period. FITL = IFITL without the video and data services (e.g. no PCDATA). If you are in the unfortunate circumstance of being located in a sub-division serviced by FITL, you are ironically, at a major disadvantage. Remember, DSL requires copper cabling, a DSL modem in your home AND a DSL modem on the other end of the copper (a DSLAM). Since FITL pushes fiber to the curb, the only copper that exists is between your home and the pedestal....and their ain't no DSLAMS in the pedestals.
got feedback?by redxii An HFC network works consists of a headend office, distribution center, fiber nodes, and network interface units. The headend office receives information such as television signals, Internet packets, and streaming media, then delivers them through a SONET ring to distibution centers. The distribution centers then send the signals to neighborhood fiber nodes, which convert the optical signals to electrical signals and redistributes them on coaxial cables to residents' homes where network interface units send the appropriate signals to the appropriate devices (i.e. television, computer, telelphone). An HFC network provides the necessary bandwidth for home broadband applications, using the spectrum from 5 MHz to 450 MHz for conventional downstream analog information, and the spectrum from 450 MHz to 750 MHz for digital broadcast services such as voice and video telephony, video-on-demand, and interactive television. Source/Reference
got feedback?by redxii SONET OC levels: OC1 - 52mb/s OC3 - 155mb/s OC12 - 622mb/s OC48 - 2.5gb/s OC192 - 9.6gb/s OC768 - 40gb/s You can divide OC circuits into what are called STS channels, or tributaries. Generally each OC level has a corresponding STS level, and higher bandwidth optical equipment can carry more than one STS channel, such as a combination of any of the following: VT-1.5 = T-1 (1.44mb/s) VT-2 = 2mb/s OC-1 = STS-1 (usually used for DS3/T3) OC-3 = STS-3c or STS3 (3 STS1 channels) OC-12 = STS-12c or STS12 OC-48 = STS-48c or STS48 OC-192 = STS-192c or STS192 OC-768 = STS-768c or STS768 (have not encountered these systems yet) SDH equivalents: STS-3c = STM-1 STS-12c = STM-4 STS-48c = STM-16 STS-192c = STM-64 The "c" in STS3c or OC3c stands for concatenated, meaning that the entire 155mb/s is dedicated to one channel (one payload), unlike an STS3, which would be 3 STS1 channels (3 payloads). For instance, on an OC12 ring, you could have 9 STS1 channels and 1 STS3c channel, or 3 STS3c channels and 3 STS1 channels. Once the channels are demultiplexed, they are split into tributaries, the lower-bandwidth interfaces used for connecting to other networking equipment. Each OC level can be a ring interface to a UPSR (Unidirectional Path Switched Ring) or BLSR (Bi-directional Line Switched Ring). On these rings, generally one line goes east, and another west. If one side fails, individual STS channels (UPSR) or the entire line (BLSR) can be switched to the other path or span, depending on the technology.
got feedback?thnx for such a detailed info.... 2009-04-21 12:48:12 by cob_ 2. Forum Links
got feedback?by redxii got feedback?by redxii got feedback?The new URL is http://www.martindalecenter.com/ 2010-08-04 15:47:04 (aefstoggaflm by redxii got feedback?by redxii Don't be alarmed. Your ISP might have a "private domain", so you get a 100% loss with a high first hop ping. To test your first hop, do a trace route to your favorite website in MS-DOS prompt. Example: tracert yahoo.com Tracing route to yahoo.com [216.115.109.6] over a maximum of 30 hops: 1 10 ms 10 ms 10 ms xx.xxx.xx.xxx
got feedback?by redxii 4.1 Level 3
Source: Level 3 got feedback?by redxii
Level 3 runs single mode fiber optic cable to the customers premise. The fiber cable can have any type of hardware on both ends. For example: 100BT Ethernet / Gigabit Ethernet: If a customer needs Gigabit Ethernet, Level 3 will have a Cisco router with a Gigabit port on their end.  The customer will have a Gigabit switch with a GBIC (Gigabit Interface Converter) connected to the fiber optic cable.  Optical Carrier Level connections and SDH: If POS type connection is requested, expensive hardware must be used by both ends. Level 3 will use Fujitsu Multiplexers:  The customer will need an OC level router, such as the Juniper Networks M20:  Serial Connections - DS3/T3: The telco needs to run a dedicated DS3 circuit. The customer needs to have a DS3 Inverse access multiplexer and a router supporting HSSI (High Speed Serial Interface). One of the HSSI compatible routers is a Cisco 3600 Series: 
got feedback?by redxii Source: Level 3 got feedback?by redxii  got feedback?by redxii got feedback?by Oxygen 4.3 SwitchPoint
SwitchPoint Network's Digital Switched Data Network™ (DSDN™) is a proven, commercially available third-generation (3G) broadband technology that enables the deployment of 100 Mega bits per second (Mbps) last-mile networks. DSDN leverages the advantages of proven indoor Ethernet Local Area Network (LAN) technology for use in large scale, outdoor residential and small business networks. Superior in performance to second-generation last-mile technologies such as cable modem and DSL, and lower in cost than other 3G technology alternatives such as fiber-to-the-home (FTTH), DSDN combines standard fiber and Category 6 (Cat6) cable with SwitchPoint's switches, network protocols and software to provide affordable broadband Internet access with upload and download speeds of 100 Mbps. Source/Reference
got feedback?by redxii Source/Reference
got feedback?by redxii
working on 10 Gbps. Most proposed fiber deployments currently provide only 10 Mbps to the end user. •Scalability - Both FTTH and DSDN can scale and have robust architectures that are full duplex and switched. Ethernet is an extremely robust system for data transfer, whether through FTTH or DSDN. •Redundancy - DSDN intelligently re-routes network traffic around any accidental cable cuts or path disruptions resulting in uninterrupted service to the consumer. Most FTTH systems are home-run strands from either the NOC or a major hub to the home. It takes either intelligent components in the field (DSDN), or redundant home run fiber from a second location (very expensive) to achieve redundancy. •Ease of Implementation and Maintenance - DSDN is easier to implement and maintain and does not require additional customer premise equipment. FTTH implementations are more difficult and require special handling for each fiber drop to the home and the installation and maintenance of active optical switching equipment at the customer's premise. Cable cuts on a DSDN network are easy and inexpensive to locate and repair. A cut to fiber requires expensive equipment to locate the cut and extensive labor and equipment to repair.
got feedback?by redxii Source/Reference got feedback?by redxii
broadband access of at least 100 Mbps. This is at least 2,000 times faster than a 56 Kbps dial-up modem, 14 times faster than the maximum speed of DSL, and ten times faster than today's maximum speed of a cable modem. •Low Cost - Deployment costs for DSDN are comparable to less robust second-generation alternatives and significantly less expensive than comparable FTTH solutions. DSDN technology delivers the performance of FTTH without the high cost of installing fiber optic cable to the subscriber's premises. While FTTH deployments can cost in excess of $3,000 per home, DSDN can be deployed for under $1,000 per home passed. •Proven - The SwitchPoint DSDN solution has been in commercial operation more than two years and has provided broadband services to thousands of customers. SwitchPoint deployed DSDN to more than 10,000 homes and 2,000+ customers in two test markets in Utah and is now marketing DSDN to network builders and operators. •Upgradeable - DSDN is engineered for upgrades to 1 Gbps with a simple DSDN switch replacement; no new cable or construction is required. DSDN can cost effectively scale to deliver multi-gigabit bandwidth performance that matches FTTH, at a fraction of the cost. •Scalable - DSDN networks will scale to support any number of homes covering a market of any size and are compatible with Metropolitan Area Networks (MAN) for their backbone traffic. •Flexible - The SwitchPoint DSDN solution is extremely flexible and can be deployed as a stand-alone 100 Mbps data network or as an overlay to new or existing HFC cable networks or power grids. •Deterministic - Each user in the DSDN network is connected to an individual 100 Mbps port on the closest DSDN switch and do not share their ports with other users on the network. The fully switched nature of DSDN architecture maximizes available bandwidth and guarantees performance for users. Flat, non-switched architectures such as cable modem networks share bandwidth with all users on the network, causing effective throughput to diminish at peak loads. •Symmetrical - DSDN provides symmetrical, full-duplex bandwidth, which means that users simultaneously can send and receive up to 100 Mbps of data. In contrast, upload speeds of cable modem and DSL are significantly lower than their maximum download speeds preventing effective deployment of premium services that require symmetrical bandwidth such as videoconferencing, VPN and interactive gaming. •Standards-Based - DSDN is fully compatible with standard Ethernet and IP protocols; works with standard networking equipment and does not require specialized customer premise equipment, such as a modem. •Reliable - Neighboring DSDN nodes can be connected to each other through redundant Cat6 links. Even if a cable is cut, DSDN's multi-path routing capabilities easily work around the affected area to deliver continuous service. •Secure - The DSDN network is an all-switched network. Security is enhanced in an all-switched network because all users on the network do not receive all packets. In flat network architectures such as cable modem, fixed wireless and some FTTH broadband platforms, this level of security is not possible.
got feedback?by redxii 5. T-1 Connections
T-1 lines are a popular leased line option for businesses connecting to the Internet and for Internet Service Providers (ISPs) connecting to the Internet backbone. The Internet backbone itself consists of faster T-3 connections. T-1 lines are sometimes referred to as DS1 lines. Note: T-1 comes in either copper or fiber optics. Source/Reference
got feedback?by redxii got feedback?by redxii 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.
got feedback?by redxii 6. T-3 ConnectionsT-3 lines are used mainly by Internet Service Providers (ISPs) connecting to the Internet backbone and for the backbone itself. T-3 lines are sometimes referred to as DS3 lines. DS3's are most often delivered via a fiber optic connection mostly an OC-3. They are split from a multiplexer (Fujitsu FLM are popular in the US). Many DS3's can be split from a single Mux. Source/Reference
got feedback?by redxii got feedback?by redxii 7. Optical Carriers
Each channel is 51.85 Mbps. An OC-3, for example, has 3 channels adding up to 155.52 Mbps. Currently, Cisco CRS-1 System features OC-768 line cards. These cards are priced at $2,000,000 USD each.
got feedback?by redxii DWDM works by combining and transmitting multiple signals simultaneously at different wavelengths on the same fiber. In effect, one fiber is transformed into multiple virtual fibers. So, if you were to multiplex eight OC -48 signals into one fiber, you would increase the carrying capacity of that fiber from 2.5 Gb/s to 20 Gb/s. Currently, because of DWDM, single fibers have been able to transmit data at speeds up to 400Gb/s. And, as vendors add more channels to each fiber, terabit capacity is on its way. A key advantage to DWDM is that it's protocol and bit-rate independent. DWDM-based networks can transmit data in IP, ATM, SONET /SDH, and Ethernet, and handle bit-rates between 100 Mb/s and 2.5 Gb/s. Therefore, DWDM-based networks can carry different types of traffic at different speeds over an optical channel. Source/Reference
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