[Asterisk-Users] IAX2 tolerance on packet losses

[Ernest Raspberry]

Hello,

I'm experiencing some problems with running IAX2 protocol on quite
reliable link with G729A codec. My customer has 2mb FR link to the
Internet used in about 20%. Ping statistics:

50 packets transmitted, 49 received, 2% packet loss, time 49496ms
rtt min/avg/max/mdev = 9.308/13.126/33.307/4.851 ms

Everything would be great, but the quality isn't good enough. I have
2mb/512kb DSL line,
on which voice calls are working muuch better.

I've checked it on many ways. Hping tells me, that the average UDP
packet loss rate is about 8-15%. Is that too much for IAX
retransmissions ability? I've setup jitter with default settings
from iax.conf, but the quality remains almost the same - it's still
tooo jiiiiitttteery every few seconds.

I ran out of ways to test it. The conclusion remains the same - delays
and delay changes should be good enough, but the packet losses remain
too. I see some VNAK requests in
my log files, but no more than 3-4 during ~40 seconds connection.

So should I fight the packet losses or tune my iax.conf options?

--
Redargs,
Ernest Raspberry