[asterisk-users] Teliax problems, they say use SIP, more mature & better working than IAX

[Scott Plante]

We have a Teliax IAX trunk that we use as an overflow for our four 
regular business lines into our local Asterisk PBX (Trixbox). We have 
our Teliax account set up so that it goes to a Teliax voicemail box if 
it cannot reach our Asterisk server, and we have the channel set up for 
5 simultaneous connections. Occasionally, calls are sent to the Teliax 
voicemail box for no apparent reason. In this case, we get this message 
in our local Asterisk log:

DEBUG[3129] chan_iax2.c: Raw Hangup 07.174.202.3:4569,src=0, dst=214

I've done tests on the weekend where I'm calling with one and two phones 
continually. Once the local asterisk box picks up, I hang up. There is 
no other traffic at the time. One time I did 75 calls in about 25 
minutes, and 9 of them failed this way and went to voicemail. Another 
time, 88 calls went through fine, then 4 went straight to voicemail. 
Most of the time I was dialing from two phones simultaneously. In no 
case did one of the two calls go through while the other failed. However 
it was usually only seconds after a successful call, and seconds after 
calls would go through successfully again. During this period I was 
connected to the Asterisk box from a remote location (where I was 
placing the calls to the Teliax number), so I don't think the entire IP 
connection was going out. I was the only one placing any calls in or out 
of the Asterisk box during these tests.

The Teliax support person (note the IAX in the name) wrote: "You may 
want to try changing to SIP as it is a more mature protocol and seems to 
work better in general." Is it the general experience on the list that 
SIP is more mature and reliable than IAX? We like the fact that we don't 
have to open inbound ranges of ports for IAX to work. We are in Atlanta 
and we're connecting to a Teliax POP in Colorado. They've been talking 
about opening an Atlanta POP since at least April of last year. Do you 
think a provider with a closer point of presence would not have this 
problem so much? Considering the fact that we do see a message in the 
logs, and that we are able to keep up other IP streams, would you agree 
the problem is not our general IP connectivity? Any idea what in general 
causes the "Raw Hangup" message appearing in our logs and is it likely 
to be on our end, their end, or either? 

Scott