On Tue, 2004-01-06 at 01:39, Jan Janak wrote:
Well, if the UAs use STUN properly, that means they use STUN only when they detect a NAT that can be traversed with STUN, then it should work.
STUN will make the messages to look like they were coming from a UA in the public internet and thus the nathelper will not force the RTP proxy.
UAs behind symmetric NAT should not use STUN-obtained IP addresses (because it would be useless anyway) and send private IP addresses. In this case the nathelper module will detect that the UA is behind a NAT and force RTP proxy.
You are right. I was only looking at the call-id header field. The Grandstream UAs I was testing with (firmware 1.0.3.81 and 1.0.4.26) used RFC 1918 addresses in that field no matter what type of NAT they were behind. They fix the contact header field, though, _unless_ you they are behind a symmetric NAT.
Thanks for pointing this out to me.
Thilo