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Walkthrough Wednesdays

CME to IP - IP to H323 gateway to PRI/PBX

Hopefully I can ask this question without being confusing.

I've got a branch site where we just installed a CME. The CME has it's own dialtone and everything is working as planned.

At their main location, we dropped in a voice 2901 to do h323 over the IP WAN and interface with their Siemens PBX through a PRI. To add onto the mess, I have a lot of translation rules because they wanted access codes for the dialing.

Ive setup all of my dialpeers and rules, and can dial from the main site to the branch, but not vice versa. I've run debugs and have verified the correct calling/called party is showing up when the branch dials the main and also the correct outbound dial peer is being matched. Even though this is happening, when debugging the isdn interface nothing shows up, which leads me to believe the d channel is never signaling.

This is mainly my question. The h323 gateway is setup as the network side for isdn. Do I need a special command to be able to send digits out of it? It will receive them, but not send.

Attached is the h323 gw config for the main location which has the matched outbound dial peer but is not dialing. Thank you in advance!



Try changing your incoming voice setting


interface Serial0/0/0:23

no ip address

encapsulation ppp

isdn switch-type primary-ni

isdn protocol-emulate network

isdn incoming-voice voice

trunk-group PRI


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Regards, Alex. Please rate useful posts.

Originally it was set to isdn incoming-voice voice. I was browsing through a PBX interoperability guide which outlined using modem, which is why it is changed. Same scenario with the isdn voice command.


Can you aslso add the controler to the trunk group


controller T1 0/0/0

trunk-group PRI timeslots 1-24

Please rate useful posts.

Regards, Alex. Please rate useful posts.

The command is not available in controller configuration. Is there a variation of it?

The command is 'pri-group', that you should have already. You can check PRI with "show controllers T1", "show isdn status".

The PRI is configured and working properly, the trunk-group command is not available in controller configuration mode.

Lets forget about the trunk group.. I'm going to remove it from the config and point the dial peers back to the port. The issue is, when a call is made it is matching the dial peer but the call is not being setup on the ISDN port. Doing a debug, nothing displays on the screen but you can clearly see the voip dial-peer in the previous match.

Edit: IOS voice reference shows controller trunk-group for CAS connections.

That is caused by no dial-peer matching. I have not fully check your configuration, as it has to be seen what the router receives, using debug out that you have not posted. If you do that, there is no need to use attachments.

Found the issue, related to a new feature called toll fraud prevention.

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