BriCrossCable
When using a BRI ISDN card in NT mode (Network Termination), a crossed cable must be used.
This cable also needs (depending on the cards port) 100Ohm resistor termination.
3/4 and 5/6 are the crossed lines.
For the termination, you need to place a 100 Ohm resistor
* between 3 and 6
and one
* between 4 and 5
on both sides.
(It seems to work with termination on one side only too when the cable is short)