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New Member

a question about transcode

Centralized CCM cluster. G.729 used for the calls cross the WAN. G711 for local lan. Each remote office has its own PRI GW. We have conference DSP created on each remote router and we have transcoder set up in the 6608 in central for unity trancoder(UNITY is setup for G711only). My question here is: If phone A in central called phone B in remote office and B forwarded to his cell phone. In this case, will there be any transcode involved? Obviously A call B use G729 and forward to cell phone is going to be G711. But I didn't see any transcode resource being used on the central. Maybe the PRI DSP will do the transcoding?Thanks

New Member

Re: a question about transcode

Hi -

In that situation, the outbound PRI at will transcode from g.729 to PSTN speak. Assuming that the PRI in the remote office is doing the outbound for phone B that forwarded to the cell phone.

In general, when you have a g.729 call destined for the PSTN, the gateway that the call goes out will have the resources neccessary to transcode the call to standard PSTN signaling.


New Member

Re: a question about transcode

I guess you must have support for more than one codec at the gateways. The call WILL be G729 all the way up to the Gateway. THe Gateway will Transcode from G729 to G711 on the audio heading out the PRI and G729 towards the phone. The transcoder in the Central site will be used when call need to get trascoded between devices (excluding Gateways) at the central site only unless the Transcoder is part of a media resource group available by all sites.