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New Member

G.729 Implementation

I would like to use g729a since I have 3 remote sites with limited bandwidth that will use a Unity (voicemail only) server at the host site. I have seen several problems with poor quality default recordings, doesn't work at all, etc. Does anyone have a solution where I can use 729 on the wan and then convert to 711 for voicemail only?<br><br>

6 REPLIES
Gold

Re: G.729 Implementation

I have seen problems with distortion on the voice prompts in G.729 but never a situation where it does not work at all. If the distortion is the problem, you can open a TAC case and we can get a G.729 optimized set of voice prompts to you.

If you want to send G.729 over the WAN and then transcode it to G.711 before it hits the Unity you will need a hardware transcoder such as the WS-X6608 card for the Cat6k.

As a side note, silence detection does not work it G.729 mode. If a customer wanted to run G.729 over the network but still needed silence detection they will need to transcode to G.711.

Keith

Keith Chambers
Customer Support Engineer
Cisco Systems
keithc@cisco.com


New Member

Re: G.729 Implementation

Do you have an idea of when the silence detection will be available?

Anonymous
N/A

Re: G.729 Implementation

Sorry, not at this point. We are still looking into it.

Gold

Re: G.729 Implementation

We have no ETA at this point.

Keith

Keith Chambers
Customer Support Engineer
Cisco Systems
keithc@cisco.com

Anonymous
N/A

Re: G.729 Implementation

That can be done with the use of transcoders, but that hardware is completely outside the realm of Unity. There are transcoders that fit into the AVVID solution (blades in Catalyst switches).

Given the Unity system has met the system requirements for g729 support, it should work. However, the g729 support does lose some functionality that g711 has (like silence detect). I am not sure why you are hearing that Unity g729 support does not work.

However, I would suspect that starting a stream in g711, going to g729 and then back to g711 is going to degrade the voice quality somewhat. Can any of the CallManager folks back that thought up...or tear it down :) ???

Gold

Re: G.729 Implementation

re:
However, I would suspect that starting a stream in g711, going to g729 and then back to g711 is going to degrade the voice quality somewhat. Can any of the CallManager folks back that thought up...or tear it down :) ???

Steve is correct. The voice will only be at G.729 quality.

Keith

Keith Chambers
Customer Support Engineer
Cisco Systems
keithc@cisco.com



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