Post
by bridonca » Tue Jan 03, 2012 12:13 pm
Hopefully you have a good router, specifically one that will actually forward the ports you selected to the destination you selected. Sadly, that is not always a given.
I am a huge fan of DD-WRT, if you can install that on your router, it makes SIP VOIP routing over NAT much more sane.
As for your ATA, I have no idea how good it is, I do know that most ATA's work fine, it is usually the router that causes the problems.
See if you can find a RTP port on your ATA. When you do find it, forward that port from your router to your ATA. I would not waste my time forwarding port 5060, your SIP traffic already knows where to go, your incoming RTP audio traffic is the issue.
You might have to lower the registration time. Some routers are good enough to "forget" where to route the traffic after as little as 2 minutes. If you send a keep alive packet every 2 minutes, the router keeps that route. You probably do not have to do this if your ports are already correctly assigned.
As for STUN, on the whole, it is pretty close to useless. It certainly will not fix your NAT problems, but it will tell the ATA what type of NAT you have if you have the correct ports forwarded. And if you have the correct ports forwarded, why do you need STUN?