Back to back connections

[admin_2]

I want to know the back-to-back conections possibilty , I know possiblity for serial ports, ethernet ports

Is it possible for aux, async, isdn bri, e1, t1

if yes I want to know the cable details

[#2]

You can connect two T1 cards bacK to back... or T1 CSU/DSU with a T1 crossover cable. A back to back ISDN connection is not possible.

You need ISDN switch to do that.

Search on the internet for T1 crossover cable pinouts.