Editing Digital Signal 3

{{Short description|Telephony call multiplexing standard}}
{{Refimprove|date=June 2010}}
'''Digital Signal 3''' ('''DS3''' or '''T3 line''') is a digital signal level 3 [[T-carrier]]. The data rate for this type of signal is 44.736&nbsp;Mbit/s (45&nbsp;Mb). It can transport 28 [[Digital Signal 1|DS1]] level signals within its payload. It can transport 672 [[Digital Signal 0|DS0]] level channels within its payload.<ref>{{cite web|last=McMahan |first=Emmet |title=Guide to T3 / DS3 Broadband Basics |url=http://www.business.com/guides/t3--ds3-broadband-basics-26403/ |archive-url=https://archive.today/20120728210458/http://www.business.com/guides/t3--ds3-broadband-basics-26403/ |url-status=dead |archive-date=28 July 2012 |publisher=Business.com |accessdate=9 June 2011 }}</ref>

Such circuits are the usual kind between [[Telephone company|telephony carrier]]s, both wired and [[wireless]], and typically by [[OC1]]{{citation needed|date=June 2011}} optical connections.

==Cabling==
DS3 interconnect cables must be made with true 75-ohm [[coaxial cable]] and connectors. Cables or connectors which are 50 ohms or which significantly deviate from 75 ohms will result in [[signal reflection]]s which will lower the performance of the connection, possibly to the point of not working. [http://telecom-info.njdepot.ericsson.net/site-cgi/ido/docs.cgi?ID=119151491D000103&KEYWORDS=&TITLE=&DOCUMENT=GR-139&DATE=&CLASS=&COUNT=1000 GR-139-CORE], ''Generic Requirements for Central Office Coaxial Cable'', defines type 734 and 735 cables for this application. Due to losses, there are differing distance limitations for each type of cable. Type 734 has a larger center conductor and insulator for lower losses for a given distance. The [[BNC connector]]s are also very important as are the crimping and cable stripping tools used to install them. Trompeter, Cannon, Amphenol, Kings, and Canare make some of the most reliable 75 ohm connectors known. [[RG-6]] or even inexpensive [[RG-59]] cable may work temporarily when properly terminated, though it does not meet telephony technical standards. Type 735 26 AWG is used for interconnects up to 225 feet, and Type 734 20 AWG is used for interconnects up to 450 feet.

==Pricing==
DS3 service is provided to businesses in the United States through [[incumbent local exchange carrier]] and [[competitive local exchange carrier]] communication providers. The price, much like a T1 (or DS1) line, has two primary components: the [[Local loop|loop]] (which is distance-sensitive) and the port (or the price the carrier charges to access the internet through their proprietary network).

==See also==
*[[Digital Signal 0]]
*[[Digital Signal 1]]
*[[DS4/NA]]
*[[Transmux]]

==References==
{{Reflist}}

==External links==

*[http://www.realtimet1search.com/news/article_282.html Detailed/Technical DS3-T3 Definition] {{Webarchive|url=https://web.archive.org/web/20090202121248/http://www.realtimet1search.com/news/article_282.html |date=2009-02-02 }}
*[http://pld.cs.luc.edu/telecom/documents/DS3fundamentals.pdf The Fundamentals of DS3, Technical Note, Acterna, TB-FUNDS3-B-2/01]

[[Category:Telecommunications standards]]


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