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Forcing Hardware Transcoding for Unity


I have a remote site using CallManager 4.0 and Unity 4.04 that would like to use hardware DSP resources on a 3825 router for transcoding instead of the Unity software based transcoding. I have found the reg key to edit in Unity to disable G729 software transcoding, which I assumed would force the hardware transcoding to be used but it does not work. If a user calls Unity they get reorder tone because of the locations programming requiring the call to be G729. The 3825 router is located at the head end site were Unity is also located and the Transcoding resources are registerd with Call Manager. The Transcoding resources are in the device pools of the remote phones and the Unity server. Am I programming this correctly? Shouldn't the transcoding resources kick in when it detects a call coming from the WAN that wants to use G729 arrive at Unity which wants G711?

3 Replies 3

You need to create a Media Resource Group containing the XCODES, add this to a Media Resource Group List, and apply this to the device pool that contains your Unity ports.


Aaron Please remember to rate helpful posts to identify useful responses, and mark 'Answered' if appropriate!

The Media Resource Groups, Lists and device pools have already been configured. The Xcode resource is in both the list for the remote phone and the Unity voicemail ports yet I still get a fast busy.

I've tested this and it works - however I did have a little trouble with regions setup whilst doing it, maybe your trouble is here too... Basically it works as follows:

You call Unity - so Phone A in DP A calls Unity in DP B. CM knows that a transcoder is needed, so brings one in. Then the regions setup between the phone and transcoder, and unity and transcoder is checked. So now phone A is making a G729 call to the transcoder (presuming that locations BW is available). Unity also needs to be able to make a G711 call to the transcoder, so again must have locations BW available and have G711 permitted in the regions config.

So basically you need to ensure that G711 is permitted between the DP that Unity is in, and the DP that the transcoder is in, and that bandwidth is available for it.

Easiest way to do this for testing would be to put the transoder into the same DP as Unity, and ensure that G711 is permitted within the region assigned to that DP. Then ensure that G729 is set between the region of the phone and the region of the transcoder/Unity.

And you already verified that both DPs have the transcoder available....

Aaron Please remember to rate helpful posts to identify useful responses, and mark 'Answered' if appropriate!
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