Hi!
IIRC we recently had a discussion about SIP outbound [1] and the benefits of an implementation in Kamailio. Just playing around with a SIP client on an iphone I discovered a usecase. Whenever the iphone gets a new IP address (quite often as it often changes between WiFi and 3G) the client reREGISTERs with the new IP address (establishing a new TCP connection). This leads to lots of "broken" registrations and TCP connections [2].
By use of SIP outbound and re-registration using the same "reg-id" the proxy would be able to replace the old registration with the new registration. Further, if Kamailio would have a mapping from registrations to TCP connections it could also close the dead TCP connections.
regards Klaus
[1] http://tools.ietf.org/html/rfc5626
[2] I do not know if TCP keepalives (socket option) could detect broken TCP connections without making too much noise on the receiver side (activating the background application and draining battery)
2011/4/28 Klaus Darilion klaus.mailinglists@pernau.at:
IIRC we recently had a discussion about SIP outbound [1] and the benefits of an implementation in Kamailio. Just playing around with a SIP client on an iphone I discovered a usecase. Whenever the iphone gets a new IP address (quite often as it often changes between WiFi and 3G) the client reREGISTERs with the new IP address (establishing a new TCP connection). This leads to lots of "broken" registrations and TCP connections [2].
...which is UGLY !!! as it causes annoying timeouts due to the false parallel forking.
By use of SIP outbound and re-registration using the same "reg-id" the proxy would be able to replace the old registration with the new registration. Further, if Kamailio would have a mapping from registrations to TCP connections it could also close the dead TCP connections.
Yes. I know that the IETF produces lot of garbage, but RFC 5626 (Managing Client-Initiated Connections) is a good stuff (and needed, specially in SIP scenarios which mobile clients).
Iñaki Baz Castillo writes:
By use of SIP outbound and re-registration using the same "reg-id" the proxy would be able to replace the old registration with the new registration. Further, if Kamailio would have a mapping from registrations to TCP connections it could also close the dead TCP connections.
Yes. I know that the IETF produces lot of garbage, but RFC 5626 (Managing Client-Initiated Connections) is a good stuff (and needed, specially in SIP scenarios which mobile clients).
the rfc looks ok, but are there any sip UAs that could be used in testing the possible sr implementation?
-- juha
2011/4/29 Juha Heinanen jh@tutpro.com:
Yes. I know that the IETF produces lot of garbage, but RFC 5626 (Managing Client-Initiated Connections) is a good stuff (and needed, specially in SIP scenarios which mobile clients).
the rfc looks ok, but are there any sip UAs that could be used in testing the possible sr implementation?
I don't know but, what was before: the chicken or the egg? :)
On 4/29/11 8:45 PM, Iñaki Baz Castillo wrote:
2011/4/29 Juha Heinanenjh@tutpro.com:
Yes. I know that the IETF produces lot of garbage, but RFC 5626 (Managing Client-Initiated Connections) is a good stuff (and needed, specially in SIP scenarios which mobile clients).
the rfc looks ok, but are there any sip UAs that could be used in testing the possible sr implementation?
I don't know but, what was before: the chicken or the egg? :)
It does not matter, the question here is who wants to be the father (or the mother) for the chicker or for the egg :-) Cheers, Daniel
-
Daniel-Constantin Mierla -
Iñaki Baz Castillo -
Juha Heinanen -
Klaus Darilion