[Serusers] SRC Port change

[Nils Ohlmeier]

Hello,

On Thursday 03 November 2005 07:12, Ritesh Jalan wrote:
> Pls. help us in resolving the problem that the SIP proxy server changes the
> Source and Destination port while replying for message. Pls. find the below
> message for the Reference In below message A cisco ata device (which is
> behind NAT with IP 192.168.10.52) is trying to register it self with SIP
> proxy server IP 172.16.101.10 with SRC port 5060 and DST port 5060, but
> when SIP proxy server replies back to the message the port number gets
> changed i.e SRC port 53492 and DST port 5060. Is there any way by which we
> can fix this port num.

ask Cisco for a fix.
But from a protocol perspective there is no need for a fix. Asymmetric 
signaling (srcport != dstport v dstport != srcport) is completely legal in 
3261. Only the rport (RFC3581) extension requires symmetric signaling. But as 
far as I know Cisco has or at least had also some problems with implementing 
rport support correctly.

  Nils