No ringback when an IPphone Cisco call a DECT ASCOM by a gateway H323

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Apr 14th, 2008
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I've a call manager 4.2(3). Last week, we have installed a gateway ASCOM for put phones DECT to telephony over IP. On the call manager, I configure a gateway H323.

Everything is ok but one thing. When an IPPhone connected to the call manager call a DECT, IPPhone Cisco don't have ringback. Yet, DECT ring and after, communication is OK.

In the other direction, it's ok.

Why ?


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jean-christophe... Mon, 04/14/2008 - 23:21
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I tried the solutions proposed by Cisco but that does not change.

On my diagram (see attachement), when phone 7911 call DECT1, phone 7911 don't have a ringback. we don't have tonality. And meanwhile, DECT1 ring.

In attachement, I put the configuration of my gateway.

Aaron Dhiman Tue, 04/15/2008 - 07:01
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What is the connection between the Borne IP-DECT (IPBS) and the Innovaphone IP6000 (proprietary digital, analog)?

Get a "debug cch323 h225" during a call setup.

Also, post "sh call act voice br" once you are ringing and again when you answer.

etmarcof Tue, 04/15/2008 - 07:41
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If you have a cisco Gateway for PSTN try to config a voip dialper to IP-DEct gateway and use related commands to force ringback ,instead of configuring IP-Dect as H.323 of Callmanager.

jean-christophe... Wed, 04/16/2008 - 04:34
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I forgot one thing on the diagram, beetween IP6000 and IPBS, we have an IPBlade (see attachment).

And I add the log of my gateway IP6000 and of my IPBlade.

In the protocol H323, what information indicates to play ringback ?

Aaron Dhiman Wed, 04/16/2008 - 06:20
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The messages in the IPBlade.txt file shows that it is using Fast Start, and it doesn't seem to be sending Progress Indicators (PI). Have you tried to enable "Outbound Fast Start" on the CallManager GW config? NOTE: It requires an MTP, so check the "Require MTP" box as well, and make sure to have an MTP available. You might want to use G.711 to enable you to use the CM as an MTP if you don't have hardware MTPs available:

Be sure to Reset the GW from the CM Admin page after making the changes.

networkdefence Mon, 05/05/2008 - 14:57
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Sorry to but in on this thread but I have also exactly the same issue for a customer as you are having.

We have a customer who is running call manager 4.1.(3) sr6, did you ever resolve this problem as i'm trying to resolve this issue with Cisco at the moment.

Also more importantly can you forward a dect phone to an analogue phone? If the customer rings from a 7911 phone to a dect and then this is forwarded to an analogue phone it doesn't work. However if the call forwards to an ip phone it works fine!.

We need this working for the customer as they use a third party voice mail via analogue ports and currently this isn't working.

If you could let me know whether this works I would really appreciate it. The customer wants this working by the end of the week otherwise he's going to scrap the IP based Ascom system and go back to an analogue dect system!




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