[asterisk-users] Diagnosing dropped calls...

[John Faubion]

>Try dropping the IAX2 and only use SIP.  Don't ask "why?"  

Well in our case we were NOT using IAX at all. Strictly SIP.

>You could be hitting an overloaded router or whatever along 
>the way, 10mbs fiber does not mean low latency or lost packets.

So true, hence the reason I suggested using mtr to check it. Many times in
our case we saw gateways between networks that were dropping packets
presumably  due to overload conditions. RTP traffic over UDP would add far
more load than the ICMP packets used for mtr.

>Seriously though, if your business lives and dies by the 
>phone system, get T1 with SIP from your provider directly 
>(point to point) with G729 or just get a real ISDN or POTS lines.

With this particular customer we initially had unrealistic time and budget
constraints. We had 11 days between when they contacted us and when the
system had to be in place. With an average install time around here of 30-35
days that ruled out the T1. Their initial monthly telephone budget was $150
per month. Like I said, unrealistic.

>Usually, once they perceive a problem, then even if the other 
>side of the call is on a cell and the cell drops the call, 

Again so true. This customer got to the point that if a call dropped when
they we on their cell phone, regardless of the fact that the call was not
going through our system, we got a trouble call. Thankfully, a week after
cutting over to the T1 we called them to make sure they hadn't found someone
else. 8)

John