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FW: VOIP G.729a [7:87607] posted 04/22/2004
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Every company's VOIP installation is different, because the actual codec may
reduce the voice from 64K PCM to 8K G729, but then you have a signalling
channel RTCP you have the rest of the RTP packet itself, etc and so forth.
Plus you can run RTP compression which can affect BW. Also there are
different forms of G729 codec which affect BW. Also silence suppresion can
affect the general BW, as well as packet sample size. (Is it a 30ms sample
or a 20 ms sample, etc) Most vendor's publish (I don't know if Cisco does) a
BW cross-reference table for all these features. Also please add 10/15% or
something reasonable to any calculation if you want it to work well. Shoving
prioritized voice down a pipe that is at utilization of 100% is still not a
good thing to do. A lot of Cisco routers will do it, but your voice quality
will ultimately suffer.

David


-----Original Message-----
From: nobody@xxxxxxxxxxxxxx [mailto:nobody@xxxxxxxxxxxxxx]On Behalf Of
Abhishek
Sent: Thursday, April 22, 2004 6:30 AM
To: cisco@xxxxxxxxxxxxxx
Subject: VOIP G.729a [7:87607]


Hi,
Can any one tell me  what is the typical bandwidth needed for a single VoIP
call (including layer 2) when Codec G.729a is used ?
One of my refrence book says, its 8kbps and other says 29.6kbps..

I am confused.. plz help me out



Thanx in advacne


Abhishek
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