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CVP supports mixed G.711 and G.729

"CVP supports mixed G.711 and G.729"


Where do you configure the allowed codec(s)?


Also, if the ingress gateway is also the vxml gateway and the ingress is SIP with g729 only (so no midcall renegotiation) but the vxml call leg is g711 -- how do you specify the transcoding resource to be used? If I change the vxml call leg to use g729 (flat codec) also, do I still have to go through the whole hex editing thing mentioned here ( I couldn't find any mention of this in the later CVP release notes, so not sure if it's still needed.




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You configure them on your

You configure them on your dial-peers and region setting in CUCM.

To engage xcoder you can use LTI, though not sure if this is supported with CVP:

Ideally you would want codec renegotiation supported by your carrier.

As to using G729 wav files, you do need to convert them as described.




Thanks for the quick reply

Thanks for the quick reply Chris!

"You configure them on your dial-peers and region setting in CUCM."

CUCM isn't involved yet though unless I'm missing something (which isn't as rare as I'd like). CVP sets up the VXML call leg from the ingress gateway to the VXML gateway (same device here) right? Does it just use the same dial-peer level codec(s) as you are allowing in your cube->cvp call server dial-peer? Is that what you mean?


LTI looks pretty slick, but I can't find any info regarding compatibility with CVP although I'm not entirely sure how that codec selection (ingress gw to vxml gw) works. Codec renegotiation is out unfortunately. It's g729 ingress with every call transcoded at the CUBE to g711. Trying to retroactively fix this and other design flaws and we'll have to move the agents to g729.


Looks like we either transcode for the VXML call leg or migrate that to g729 as well. Seems like transcoding gives us the flexibility to add asr/tts at a later date if/when requirements change. On the other hand, using a flat codec end to end makes troubleshooting easier and frees up those dsp's. Any advice/experience to share one way or the other?




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