[asterisk-users] IAX vs SIP

[Edgar Guadamuz]

Hello,

I have been testing a trunk IAX and another SIP, using sipp to
generate SIP calls to a Asterisk box.


The testing dialplan just connects to another Asterisk box, who
answers the call and playback some files.

I noticed that the cpu load is higher when I use an IAX, about 90% for
25 simultaneous calls. In the other hand, with a SIP trunk the cpu
load was about the half or less.

In both cases the Asterisk box was in the middle of the RTP path, and
both the trunk and the sip client had the same codec, ulaw.

Does it make sense? Why is IAX demanding so much cpu load?