Most CPE techs are familiar with T1 circuit IDs that look something like the following:
"95/HCGS/241396/NE".
That type of T1 circuit runs between an end user and a service provider.
Circuits that run between switches, (LEC->LEC, LEC->CLEC, LEC->IXC...etc), have IDs that look something along the lines of the following:
8001/T1/BSTNMACODC1/CMBRMAWADC0 or
8002/T1ZF/BSTNMACODC1/CMBRMAWADC0
The ID breaks down like this:
Circuit Carrier Number/Line Coding Type/"A" end Cilli/"Z" end Cilli.
T1 = AMI
T1ZF = B8ZS.
As a CO tech, I work with all of these kinds of circuits.
