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Codec Selection Between CUCM and CUBE


We have a CUCM 7 cluster with SIP trunk through a CUBE (ISR 2821) to our phone service provider. The service provider prefers G.729 as primary codec and falls back to G.711 when needed.

On the CUBE, I set up a codec voice class with G.729 for preference 1 and G.711 for preference 2, on all SIP dial peers. Between the CUCM and CUBE, the region setting is G.711. The result of this configuration is: for outgoing calls from CUCM to PSTN, G.729 is selected normally; however, for incoming calls from PSTN to CUCM, G.711 is selected normally. From my understanding, the called party proposes the Codec preference to be used. So when CUCM is being called, the region setting takes effect, and G.711 is being used, although G.729 is allowed.

My ideal design is for incoming calls, G.729 is also preferred as the primary codec.

The requirements are:

1. We still need G.711 in the picture as secondary codec, since we have both contact center and unity applications which use G.711.

2. I do not want transcoder to be in the picture, unless there is no possible workarounds.

Is there any good solution? Help is highly appreciated.


Cisco Employee

Re: Codec Selection Between CUCM and CUBE

Hi Load 15.1(2)T and there is a CLI under Voice-class codec called offer-all this CLI will offer all codec's under the VCC and not look at the incoming leg.