Voice Over IP in UK - Using Asterisk to simulate an ISDN2e line

Author

Using Asterisk to simulate an ISDN2e line

Ron Wellsted

2006-08-25, 7:11 pm

I am trying to get 2 Asterisk servers to communicate over an ISDN2e line.

Each is running Asterisk 1.2.10 + Bristuff driving a HFC-S chipset BRI
card. One is configured as bri_net_ptmp, the other as bri_cpe_ptmp.

I have built a crossover cable wired as

(Rx+) 3 ------ 4 (Tx+)
(Tx+) 4 ------ 3 (Rx+)
(Tx-) 5 ------ 6 (Rx-)
(Rx-) 6 ------ 5 (Tx-)

However the slave (cpe) Asterisk box always reports that the
D-channel is unavailable. While the master (net) box seems happy.

Changing to ptp mode (bri_net and bri_cpe signalling) causes both boxes to
report a lack of D-channel.

Can anybody tell me where I am going wrong?

--
Ron Wellsted
ron@wellsted.org.uk http://www.wellsted.org.uk
N 52.567623, W 2.137621 Linux Counter No. 202120
FWD:519961

Thomas Kenyon

2006-08-26, 7:11 am

Ron Wellsted wrote:
> I am trying to get 2 Asterisk servers to communicate over an ISDN2e line.
>
> Each is running Asterisk 1.2.10 + Bristuff driving a HFC-S chipset BRI
> card. One is configured as bri_net_ptmp, the other as bri_cpe_ptmp.
>
> I have built a crossover cable wired as
>
> (Rx+) 3 ------ 4 (Tx+)
> (Tx+) 4 ------ 3 (Rx+)
> (Tx-) 5 ------ 6 (Rx-)
> (Rx-) 6 ------ 5 (Tx-)
>
> However the slave (cpe) Asterisk box always reports that the
> D-channel is unavailable. While the master (net) box seems happy.
>
> Changing to ptp mode (bri_net and bri_cpe signalling) causes both boxes to
> report a lack of D-channel.
>
> Can anybody tell me where I am going wrong?
>
I personally thought that you didn't use a crossover in this arrangement.

I wouldn't know though. You'd be better off asking on the asterisk-users
mailing list. There are a lot more ISDN users on there.