[SIPForum-discussion] Choosing the best response. Clarification needed

[Yevgen Krapiva]

So, everything is okay then. Thanks.

2009/5/13, Tomasz Zieleniewski <tzieleniewski at gmail.com>:
> 2009/5/13 Yevgen Krapiva <ykrapiva at gmail.com>
>
>> Yes.
>>
>> >then proxy sends final response when all transaction end.
>>
>> It will happen when Timer D fires.
>>
>> >so an absolute minimum of 32s is used instead of basing Timer D on T1.
>>
>> Am I (UAC) supposed to wait 32 seconds before I get an answer from
>> proxy that my request failed ?
>
> No this timer is required for the purpose of ACK retransmissions.
>
>> It's too long. O_o
>> I'm saying that proxy must not wait when client transaction finally go
>> to terminated state. I think that COMPLETED state already gives me a
>> right to send the final response to UAC. Why not ?
>
> Stateful proxy core may start processing of the corresponding server client
> transactions as
> soon as all client transactions move to completed state.
>
> Best regards,
> Tomasz
>
>>
>>
>>
>>
>> 2009/5/13, Tomasz Zieleniewski <tzieleniewski at gmail.com>:
>> > Hi,
>> >
>> > I think You have mistaken the completed with terminated state.
>> > When proxy receives 300-699 response this causes a proxy client
>> transaction
>> > to
>> > transition to completed state. In which for unreliable transport it
>> starts
>> > D
>> > timer
>> > in order to generate ACK for transaction response retransmissions.
>> > When D timer fires transaction transitions to completed state. (proxy
>> > removes any associated resources)
>> > Keep in mind that this a per transaction behavior. When there is
>> > forking
>> at
>> > the proxy
>> > if the response is not 6xx or 200 then proxy sends final response when
>> all
>> > transaction end.
>> >
>> > Kind regards,
>> > - Tomasz Zieleniewski
>> >
>> > 2009/5/12 Yevgen Krapiva <ykrapiva at gmail.com>
>> >
>> >> Hi.
>> >>
>> >> Here is a quote from RFC 3261 Response processing section in statefull
>> >> proxies:
>> >>
>> >> >6.  Choosing the best response
>> >> >
>> >> >         A stateful proxy MUST send a final response to a response
>> >> >         context's server transaction if no final responses have been
>> >> >         immediately forwarded by the above rules and all client
>> >> >         transactions in this response context have been terminated.
>> >>
>> >> Should I treat the words "terminated transaction" as transaction in
>> >> TERMINATED state ? If yes, then keeping in mind that client
>> >> transactions created by proxy "live" for about 30 seconds in case of
>> >> 3XX-699 responses, then the UAC have to wait half a minute until the
>> >> proxy answers him.
>> >>
>> >> In other words: If client transaction created by proxy receives
>> >> 3XX-699 response, then it will elapse 30 seconds before transaction
>> >> goes from COMPLETED to TERMINATED state. All this time proxy have to
>> >> wait until it sends the final response to UAC.
>> >>
>> >> Is it normal ? Or should proxy choose the best response when all
>> >> client transactions goes to COMPLETED OR TERMINATED state ?
>> >> _______________________________________________
>> >> 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
>> >>
>> >
>>
>