31 Oct
2007
31 Oct
'07
11:12 a.m.
El Wednesday 31 October 2007 10:22:05 Konstantinos Koutsopoulos escribió:
The NATted device (client B) is behind a USR 9112,
the other machine (with openser and client B) is on an
academic LAN. The fact, however, is that tshark indicates
that the original sdp (from B) reaches port 5060 of openser
but the invite that is thereafter forwarded to client A
contains a modified sdp.
Not sure if I've understood, you said always "client B" XD
I assume client B calls from NAT. Is it a softphone?
Could you try with a softphone as B and do a ngrep o tshark in the **same**
machine B is running and notate the INVITE message?
Then you can do a ngrep in OpenSer and inspect the received INVITE form B.
If the NAT has been fixed "by magic" then your router (in B LAN) does ALG's,
so it rewrites the SIP message and replaces private IP with public IP and
internal ports with NAT mapped external ports.
--
Iñaki Baz Castillo
ibc(a)in.ilimit.es