[Asterisk-Dev] IAX2 Receiver Reports

[steve at daviesfam.org]

On Tue, 28 Dec 2004, Steve Kann wrote:

> Also, LAGRQ frames are presently sent to the remote side, in order to 
> get an idea of the Round-Trip + playout(jitterbuffer) delay.  The 
> implementation of LAGRQ is presently a bit broken, because they 
> currently go through the jitterbuffer on _both_ the sender and receiver 
> side, and the timestamps used to do this are wrong.  (actually, I 
> haven't checked this recently, but it was the case).

Yeah - I'd suspect that the LAGRQ/RP isn't right.  And it always seemed 
rather pointless as they aren't reported in any obvious way that I 
noticed.

Ping roundtrip + the jitter buffer delay on both sides is nicer.

The only problem at the moment is that we need to be careful that the ping 
is sent immediately, the pong reply is sent back immmediately, and that 
the jitterbuffer delay measurements added in the IEs are the delays that 
would have been added for the particular ping or pong.

But to get the right jitter buffer delay for a ping or pong is complicated 
by the fact that the ping has a timestamp that isn't consistent with 
ordinary voice frames, and - even worse - the pong has the timestamp of 
the originally sent ping...

Steve