[SR-Users] SIP outbound

[Klaus Darilion]

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)