[Asterisk-Users] Digium Wildcard T1 Compatibility (ethernet f or T1 cables)

[Michael Loftis]

--On Monday, October 25, 2004 09:36 -0400 mattf <mattf at vicimarketing.com> 
wrote:

> <snip>
> I have run several robbed-bit(non-PRI) T1s on standard CAT5e ethernet
> cable for runs of over 100 feet(30 meters) and have seen no increase in
> the error rate of the T1s. I've done this for years, and even the telco
> install techs say it really doesn't matter especially if you are running
> robbed-bit, supposedly its more forgiving than PRIs are.


A good Cat5/Cat5e cable will perform just fine at the signalling and drive 
levels of a T1 -- 3V signalling at like...hmm can't remember MHZ but if 
anyone's in that interested I'll look it up.

The problem happens in that a lot of people mis-wire them, or wire an 
ethernet crossover that doesn't' work right for a T1.  T1 uses pin/pair 1-2 
and 4-5, ethernet uses different pairs.  Then they make the crossover 
ethernet style and mess it up, or invert some of the T1 signaling pairs so 
there's a mis-match.  Or run the cable close to noise sources (fluorescent 
light ballasts are my personal bane)