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Question on Message across sites

Hi all,<br><br>I have 2 questions, hope you can help me:<br><br>If user use VMO to retreive the voice mail, is it a real time streaming from exchange to client PC? Or client end will try to download the whole message and then play to the users?<br><br>Any QoS setting is needed in the routers if we use legacy PBX (not Callmanager)? As I know, Cisco IP phone will mark the IP Precedence into 5. But in BPX environment, voice over IP only occurs in using PC to listen the VM only. Thus, in our design, we will use G729 to save the BW. Anyway, if QoS is needed, how should I configure? Using CBWFQ or others?? Pls suggest, thanks!<br><br><br><br>


Re: Question on Message across sites

Unity will stream your voice mail message real time across the network via VMO or over the phone interface. We never have to copy the entire message first (which causes a large delay and hits your network hard). This works regardless of which codec you used to record the message.

Jeff Lindborg
Unity Product Architect/Answer Monkey
Cisco Systems (new page for Unity support tools and scripts)


Re: Question on Message across sites

So, that means QoS must be concerned in the WAN routers / LAN switches, right??

Besides, from CCO, I found if user use G729a codec in the Unity. Microsoft Windows Media player doesn't support this codec, is that right?? If all users use G729a and forward the message to non-VMO client, can user listen those messages?? Thanks for your help !


Re: Question on Message across sites

If you want flawless voice quality you will need QOS. It might be difficut to prioritize that traffic. You will definitally want to get a sniffer and start disection the traffic.

The G.729 codec is more rezialent to packet loss and delay that non compressed codecs such as G.711. If a packet is missing the codec will make a guess at what it would have sounded like based on the packets before and after it.

The G.729 codec will need to be installed on the machine before it can be played back. Windows does not have it installed my default.


Keith Chambers
Unity Technical Lead
Unified Voice Team, San Jose
Cisco Systems

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