[Asterisk-Users] Maximum tollerable lag/jitter for IAX2 w/ojitterbuffer enabled?

[steve at daviesfam.org]

On Tue, 7 Sep 2004, Chris Shaw wrote:

> > All calls are running as GSM, even though g.729 is also an 'allowed' codec
> > (w/5 licenses installed). During an average call 'iax2 show channels'
> > provides:
> >
> > Peer             Username    ID (Lo/Rem)  Seq (Tx/Rx)  Lag      Jitter
> > JitBuf  Format
> > 10.0.40.140      astpbx-woo  00002/00002  00005/00006  00040ms  0036ms
> > 0000ms  GSM
> >
> 
> If you can reproduce it, this smells like a bug... IAX runs over TCP and TCP
> doesn't just disconnect sockets unless it recieves a RESET or a FINISHED or
> there's a timeout (usually like 5 minutes or more depending on your TCP/IP
> stack). Needless to say that to disconnect a TCP connection, that would have
> to be one hell of a lag spike... * must be actively disconnecting the
> connection....
> 
> I've heard the jitter buffer is a bit buggy, have you tried turning it off
> completely?

IAX runs over UDP.

Most probably this users' problem is something to do with NAT between the
two endpoints that is killing the connection between the endpoints.

The jitterbuffer is disabled - see the "0000ms" in the JitBuf column.

Steve