[Asterisk-Users] codec issues

[Scott Lykens]

On Tue, 21 Dec 2004 01:10:51 +0200, Shoval Tomer <shoval at softov.co.il> wrote:

> Now the calls sounds fine, but the bandwidth is uses is near 20K instead
> of just 6K (both phones are near me, and the Asterisk server is at a
> remote location, and I can monitor bandwidth usage in my FW).

I don't think you'll ever really see just 6 Kbps on the wire as IP,
UDP, and RTP overhead for a 30 ms sample is around 10 Kbps all by
itself. On an 8 Kbps codec like G.729 it wouldn't be unusual to see 18
Kbps of bandwidth used by the conversation.

If it were using GSM you should see about 29 to 30 Kbps as it is a 13
Kbps codec plus 50 packets worth of overhead, 16 Kbps. (20 ms samples)

I don't know why you're not seeing the same codecs indicated on both
sides but it looks to me like you are getting G.729.