[Asterisk-Users] ilbc high bandwidth

[Roy Sigurd Karlsbakk]

> Good day all
> We have 2 asterisk servers connected to each other via IAX2 using ilbc.
> Each call we make goes up to 25kbit and each one there after 25kbit as
> well

bit rate is 13333bps, giving 1667 bytes/sec
packetization is 20ms, giving 34 bytes per packet
IAX header is 4 bytes
UDP header is 8 bytes
IP header is 20 bytes
this means one packet is 34+4+8+20=66 bytes
50 packets per second gives 3300 bytes/per second, meaning 26400bps

> Is there a way to bring it down?

yes
hack asterisk to use a lower packetization value

roy