Session Manager and SBC codec configuration

[rejackson]

I am trying to figure out where the codec sets are configured in the Session Manager and the Avaya (sipura) SBC. In CM I can see the signaling group for the trunk to the SM is assigning a network region to the far end (SM). That identifies the codec list from CM to SM.

In Invites from the SM to the SBC I see it offer G.711 pcmu and G.729. In invites from the SBC to SM it offers G.711 pcmu, G.711 pcma, and G.729. I cannot figure out where those codec lists are configured in either device. Can someone point me to it?

 

[kyle555]

SM doesn't do codec negotiation - it just passes along whatever is in the original SDP from either end. I suppose it might be able to do stuff with bandwidth control where if you've got < +/-70Kbps left, reject 711 and might pass 729 but I haven't tried.

In the SBC, various codec sets are defined probably somewhere in the "media rules

 

[rejackson]

Thanks Kyle, that makes sense. I guess. So it sounds like the SM is a middle man and the SIP negotiations are passing between entities that are attached to it. They are not negotiating with the SM.