[SIPForum-discussion] Query for Time T4

[Nitin Kapoor]

Lakhan,

Timer T4 basically represents the amount of time the network will take to
clear messages between client and server transactions. The default value for
T4 is "5"seconds. Also T4 is a constant and not set based on T1.

You can refer to RFC 3261 Sec 17.1.2.2 for more detail.



Apart from that I am not sure after expiring the T4 timer, how your A party
will send you another ACK. Also 408 is for Request Time Out not for *Call
leg doesn't exist.
*



May be someone else can give the answer of your second query in more depth.



Thanks,

Nitin Kapoor




2010/1/8 lakhan patel <lakhan.p at gmail.com>

> Hi All,
>
> I have doubt about T4 Timer and what happen if any dialog is in terminated
> state and other side tries to communicate with previous dialog which was
> terminated?
>
> After INVTE from A to B, B sends *404 Not found* and B received *ACk *for
> *404* but when A-side receive *404 *and send *ACK *for *404 *Call goes in
> *Confirm* state and after *5second(T4 timer fires) *it goes under *Terminated
> *state and after that if we are sending Re-send *ACK *for *404 *it should
> reply with *408 Call leg does not exist*.
>
> *Can Any body tell me is it correct call flow or not?*
>
>
>
>
> --
> Thanks & Regards
> Shivlakhan Patel
> Email: lakhan.p at gmail.com, lakhan.p at hotmail.com
> IBM India Private Ltd. Bangalore
> Contact: +91-9902791177
>
> _______________________________________________
> This is the SIP Forum discussion mailing list
> TO UNSUBSCRIBE, or edit your delivery options, please visit
> http://sipforum.org/mailman/listinfo/discussion
> Post to the list at discussion at sipforum.org
>
>
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://sipforum.org/pipermail/discussion/attachments/20100108/f545069c/attachment-0002.html>