On Aug 15, 2008 at 10:30, Steven Wu Steven.Wu@teleca.com wrote:
Hi All,
Does SIP server at iptel.org support UDP register?
Of course it does, most of the users use UDP.
When my UA rigister to iptel.org whith UDP, the 401 response always replied by SER at port 100xx(example 10028). But in my contact of rigister port assigned to 5060. So, my UA can't recive the 401 response, register failure.
The reply does not go to the contact address (which is used only for subsequent requests), but to the source ip of the request and the port from via or from the via rport parameter. Because of the large number of UAs behind NAT, that do not support the rport extension, but still support symmetric signalling we force rport behaviour for everybody (which means we send back to the source port of the request). If your UA does not support symmetric signalling (which means it will never work from behind a NAT unless you manually forward ports on your NAT box) it would explain your problems, but I would need a captured message to tell for sure (you can send it to me privately). If I were you I would upgrade the UA, or check if symmetric signalling can be turned on from its config (it's a basic feature that any UA should support by default).
But use TCP everyting is OK?
On TCP the reply goes back on the same connection on which the request was received and probably your UA expects this and does not close the TCP connection.
Can anyone give me help?
Andrei