[Asterisk-Dev] RE: Who looks after layer 1 PRI framing?

[Haigh, Michael]

These lines very definitely EuroISDN.  The Cable and Wireless guys have
been very helpful in trying to troubleshoot this and they're happy that
the line is trying to speak the right protocols.

Cheers
Mick
 
>    I'm having a problem getting Asterisk to talk to Cable and Wireless
>    PRIs in the UK.  After a lot of looking at bits on the wire and
>    looking at the carrier switch, it seems that the carrier switch is
>    seeing an "unintentional loopback" condition and taking the PRA out
of
>    service.

Make sure the lines are EuroISDN NOT UK ISDN which is a slightly
different version which Asterisk does not support.

Most UK operators will set UK ISDN by default.