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Software Conference support for G729

As per this link

Software conference devices only support G.711 codecs. Cisco CallManager 4.0 and later also support G.729 codecs. Still, the default codec is G.711. However, if the Meet-Me conference is initiated by a phone that has a G.711 codec, G.729 devices are not able to join the meeting unless there is a transcoder involved. A transcoder is needed to handle the translation from one codec to the other one. A similar issue arises with Ad-Hoc conferences. If the phone that initiates the conference tries to include a phone with a different codec, it fails. An error message is displayed on the traces. Hardware conference devices can provide transcoding for G.711, G.729, and G.723 codecs.

This is not working for me. After changing the region to use G729 and trying to do a conference, getting a fast busy. All the IP Phones and the Conference bridge are in the same device pool. There is only one software conference bridge configured and no hardware conference resources.

Event viewer is reporting the error

Error: MtpNoMoreResourcesAvailable - No more MTP resources available.

App ID: Cisco CallManager

Cluster ID: StandAloneCluster

Looking at the event viewer error, Callmanager is trying to find a hardware resource and not using the software conference resource. Checked the Real time monitor tool for resource availability, 48 conference bridge resources available.

Has anyone tried this and made it to work? Please share your experience.




Re: Software Conference support for G729

Anup, as stated by the document Software Conference Bridge (SCB) ONLY supports G.711, so there is no way to involve other codecs on those conference without a transcoder.

The document states that CCM supports other codecs which is correct but not the SCB so is never going to work without a transcoder or a Hardware Conference Bridge (HCB).

It never says that the SCB will support different codecs than G.711 on CCM 4.0 and later.



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