On Friday 18 May 2007, Vincent Aniello wrote: > Are there cables specifically for use with T1s that we should be using > to connect circuits to our Cisco routers with integrated CSU/DSUs? We > currently use CAT5E cables and have chronic problems with errors on a > few of our circuits. The cable length between the smart jack and router > is 25 feet.
The T1's I've had experience with have all been wired RJ48S, which uses pairs 1-2 and 7-8 of the 8 pin plug (in TIA-568B that would be the orange-white and brown-white pairs). If your cables are TIA-568A or B they have the correct pairing. It's only if you have USOC RJ61 or similar that you have to worry, as that splits the pairs. One poster mentioned clocking; this I would check. What sort of errors are you getting from the controller? I have one T1 here terminated in a RSM/VIP2 in a Cat5509 using a PA-MC-8T1. Some providers have more problems with B8ZS versus AMI, and I have seen odd problems with HDSL (PairGain) provisioned T1's that were the fault of the carrier's shelf backplane. Currently, the T1 that backs up our OC3 is provisioned over fiber with an FMT-6, and that has been absolutely rock solid using a standard Cat5 cable about 100 feet long. -- Lamar Owen Chief Information Officer Pisgah Astronomical Research Institute 1 PARI Drive Rosman, NC 28772 (828)862-5554 www.pari.edu _______________________________________________ cisco-nsp mailing list [email protected] https://puck.nether.net/mailman/listinfo/cisco-nsp archive at http://puck.nether.net/pipermail/cisco-nsp/
