[asterisk-users] Set port to which Asterisk should send its answer

[Eric "ManxPower" Wieling]

nat=yes might cause this, since with NAT we cannot trust the IP or the 
port that is in the data part of the packet.

Andre Kirchner wrote:
> I'm sending the following message from port X to port 5060 of another box running Asterisk, and it is answering back to port X from port 5060. Shouldn't Asterisk use the Via header to find out where to answer, and in this case send its answer to port 4000?
> 
> OPTIONS sip:192.168.0.103 SIP/2.0\r\n
> Via: SIP/2.0/UDP 192.168.1.130:4000;branch=0.0\r\n
> CSeq: 4711 OPTIONS\r\n\r\n