RE: QOS or more bandwidth

["Kavi, Prabhu" <prabhu_kavi () tenornetworks com>]

> -----Original Message-----
> From: Pete Kruckenberg [mailto:pete () kruckenberg com]
> Sent: Tuesday, May 29, 2001 12:10 PM
> To: nanog () merit edu
> Subject: RE: QOS or more bandwidth

 <snip>
> Voice-over-IP benefits from statistical multiplexing as
> much, if not moreso, than any other application. A
> toll-quality voice call runs at ~5-6kbps (factoring silence
> suppression and RTP header compression) vs. 8kbps across
> compressed TDM.

Do you mean G.723.1? Let's put aside that some people do not
consider G.723.1 to be toll-quality.  Ignoring that, I would 
call your 5-6 kbps number to be compression rather than 
statistical multiplexing.  The voice packets still come out
periodically every 30ms or so.  The only significant statistical 
multiplexing you get with voice is due to silence suppression.

Also, how do you actually achieve 5-6 kbps when you 
consider the IP overhead?

Prabhu
----------------------------------------------------------------------
Prabhu Kavi                     Phone:  1-978-264-4900 x125 
Director, Adv. Prod. Planning   Fax:    1-978-264-0671
Tenor Networks                  Email:  prabhu_kavi () tenornetworks com
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