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DSL and Telco questions

Posted on 2004-10-04
Medium Priority
Last Modified: 2013-12-29
Hey all, I have some questions, if you could give me an explanation of each of these terms and also give me a short list of popular equipment that would be used with each, I would appreciate it.  I would look it up myself, but I want someone's layman terms to describe it, so no links please.  Thanks!

dmarc (sp?)
paragain or paragame (sp)
CO (central Office)

Thanks all!

Question by:ACSNS
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Accepted Solution

zerofield earned 1000 total points
ID: 12222305
dmarc (sp?)
paragain or paragame (sp)
CO (central Office)

demarc is where the telco's lines interface with those of another entity or another telco.  you'll also hear networkers and telco people refer to it as the location where their obligation essentially ends.  the oldschool synonym for this would be NTI.

dslam - you can think of this as a hub for DSL lines (it's really a multiplexer, but if you dont understand mux'ing and demux'ing lets skip that).  telco's must have numerous DSLAMs in order to service numerous DSL customers.  you will have a DSLAM per area/neighborhood generally.

im not sure what you mean with "pairagane" ive said it out loud a few times.. maybe if i heard the correct pronunciation it'd make sense.??..

CO is just that.. the telco's main offices.  generally you'll hear networkers use CO in reference to the termination points of lines.  if a guy installing your T1 says "they have to turn it up at the CO" it means that the line is good from your area, through the demarc, up to the CO.  this one's pretty self explanatory.

get back with me on the P-word, see if you can find the spelling for it..

Expert Comment

ID: 12222457
Hello AP-

1.  Also called a point of demarcation (abbreviated POD), the physical point at which the public network of a telecommunications company (i.e., a phone or cable company) ends and the private network of a customer begins.  This is normally in a basement or telcom room and can vary in size. - You do not need any equipment here this is where all of the wiring comes together.

2.  Short for Digital Subscriber Line Access Multiplexer, a mechanism at a phone company's central location that links many customer DSL connections to a single high-speed ATM line.  ATM is short for Asynchronous Transfer Mode, a network technology based on transferring data in cells or packets of a fixed size. The cell used with ATM is relatively small compared to units used with older technologies. The small, constant cell size allows ATM equipment to transmit video, audio, and computer data over the same network, and assure that no single type of data hogs the line. - I don't believe that you need any equipment here either.  With DSL it comes through the existing telco wires and the ISP supplies the line filters.

3.  Not sure what this is...never heard of it.  Sorry.

4.  Short for central office. In telephony, a CO is a telecommunications office centralized in a specific locality to handle the telephone service for that locality. The CO switches calls between local service and long-distance service. - This is a building that is owned by the telecommunications office and you wouldn't have any equipment here either.  

Hope this helps.


Expert Comment

ID: 12222503
the only location you need equipment of your own is the "customer premises".  you dont need to worry about any of the above locations yourself.
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Expert Comment

ID: 12222558
More info to expand on Zerofield above:

DMARC - Is the end point of any type of line ran to the customer location.  The wiring that is terminated inside you wiring closet is a good example.

DSLAM - DSLAM takes the signals from multiple DSL lines and combines them for transport across the larger ATM lines.  DSLAMS usually are located at the CO (main office), but can also be located at strategic location where they need to extend there DSL reach.

pair-gain/paragain (??) method of using concentrators and multiplexors to get more available subscriber lines out of a single carrier line - - basically a big splitter =)

Hope this helps!

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Expert Comment

ID: 12222575
Pairgain is a brand name of some networking equipment, mostly used by the telcos.
Mostly defunct today, bought out by ADC Kentrox...with some remnants

The name came from the technology:

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Expert Comment

ID: 12222802
paragain or paragame (sp)

pair gain is a multiplexing method of using a single pair for multiple subscribers. Unless it is the latest digital version it is bad news for dsl.
Also called DAML.

Expert Comment

ID: 12224972
may be you ment "Paradyne" here what is it...

Based in Largo, Florida, Paradyne is a leading developer of carrier-class, high-speed network access solutions for broadband voice, data and video. A recognized market leader in digital subscriber line (DSL), service level management (SLM), and Broadband Voice and Media Gateway solutions, Paradyne markets its award-winning GranDSLAM and BitStorm DSL systems, ReachDSL and EtherLoop products, Jetstream Media Gateway systems and iMarc Service Level Management systems to service providers and business customers worldwide.
The Company has over 32,900 DSLAMs (DSL Access Multiplexers) in the worldwide market, representing over 5 million ports of maximum capacity, and over 200,000 lines of its unique EtherLoop solution, giving service providers and hospitality networks the ability to deploy advanced services such as video over copper. In addition, Paradyne has shipped over 428,000 ports of its unique ReachDSL solution, giving carriers the ability to deliver broadband over almost any copper line, even those that are very long or severely impaired.

Paradyne’s Jetstream Media Gateway systems lead the market in the deployment of voice over DSL.

Leading carriers, including AT&T, Bell Canada, Broadwing, SBC, Sprint, Verizon, and WorldCom, have deployed Paradyne's SLM solutions into mission-critical enterprise networks.

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