An example - An UAS will respond with 500 response when it receives out of order requests. This might result in session tear down. TCP handles OOO packets in a better way and won't let such situation occur. I think one would use TCP (i.e reliable L4 ) when SIP reliabilility alone is not enough.
Thanks, Pranab On Sat, Sep 26, 2009 at 4:23 PM, Iñaki Baz Castillo <i...@aliax.net> wrote: > El Sábado, 26 de Septiembre de 2009, Pranab Bohra escribió: >> As >> Abhishek mentioned, reliability is the concern here. > > I don't understand it. You are speaking about *network* level reliability > (level 4) but since we are talking about SIP what we need is *application* > level reliability (level 5). And the fact is that SIP implements by itself > reliability in the protocol (ACK, CSeq, retransmissions...). > > Of course that SIP over TCP simplifies the reliability mechanism (basically > some transaction timers used in SIP UDP dissapear for SIP TCP) but from the > point of view of the application protocol (SIP) reliability exist for both > transport layers (reliable: TCP, and non reliable: UDP). > > Regards. > > -- > Iñaki Baz Castillo <i...@aliax.net> > > _______________________________________________ > Sip-implementors mailing list > Sip-implementors@lists.cs.columbia.edu > https://lists.cs.columbia.edu/cucslists/listinfo/sip-implementors > _______________________________________________ Sip-implementors mailing list Sip-implementors@lists.cs.columbia.edu https://lists.cs.columbia.edu/cucslists/listinfo/sip-implementors
