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what are the minimum and maximum compression rate for voice using g729 on an ethernet segment?

Manual indicates voice can be compressed at 26kbps using g729. checking with an analyzer, it showed at 56kbps. What is the min. and max. compression rate and how to configure it.

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Anonymous
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Re: what are the minimum and maximum compression rate for voice

The maximum bandwidth utilized for one voice call using Codec g729 is 26kb/s.

If you use g729 with rtp header compression the Overhead of 40byte header is compressed to about 4byte and the overall bandwidth per one call would then be

[ 8kb/s _ (1+4/20)]+ 2 =

[ 8 _ 1.2] + 2

9.6 +2 = 11.6kb/s

If you have VAD enabled, it can further reduce bandwidth by not producing rtp packets in time of silence. This can further the bandwidth consumed by voice

call by 35% hence the overall minimum is 65% of 11.6 KB/s

7.54kb/s.

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