Hi Vivek,
   what exactly eMTA is?

Regards,
Praveen

On Thu, Jun 17, 2010 at 11:42 PM, Vivek Singla <[email protected]> wrote:

> Thanks everyone for the responses to my query. I really appreciate it.
>
> So the Cseq value would remain the same in the 2nd and the 3rd BYEs here.
>
> And the 3rd BYE will get the 200OK from the P-CSCF since P-CSCF maintains
> the information for that transaction until 64*T1. And after 64*T1 if P-CSCF
> gets the BYE, it'll respond with 481.
>
> Thanks,
> Vivek.
>
>
>
>
>
>
>
>
> ________________________________
> From: "WORLEY, Dale R (Dale)" <[email protected]>
> To: Vivek Singla <[email protected]>; "
> [email protected]" <
> [email protected]>
> Sent: Thu, June 17, 2010 8:26:35 AM
> Subject: RE: [Sip-implementors] Retransmission of BYE
>
> ________________________________________
> From: [email protected] [
> [email protected]] On Behalf Of Vivek Singla
> [[email protected]]
>
> I have a scenario here in the lab :
>
> eMTA                   P-CSCF
>
> Invite-------------------->
>
> <----------------------------180
>
> <---------------------------200OK
>
> ACK---------------------------->
>
> BYE------------------------------>
>
> <--------------------------------407
>
> BYE----------------------------->
>
> <---------------------------------200OK
>
> BYE--------------------------------->
>
> <------------------------------------200OK
>
>
>
> In this scenario the second BYE ( after 407 ) gets the 200OK but after
> 500ms and therefore sends the third BYE ( retransmission ).
>
> 1) The CSeq in second and third BYEs are same ( CSeq: 3 BYE ). Is this
> correct?
>
> 2) The P-CSCF after its gets the 3rd BYE ( retransmission ), sends the
> 200OK back. Shouldn't it send 4xx saying that no transaction exist? I am
> thinking since P-CSCF has already sent 200OK for 2nd BYE, it has terminated
> the transaction and Dialog on its side. So any retransmissions of BYE from
> UAC should be responded back with 4xx.
> _______________________________________________
>
> The 3rd BYE has the same CSeq (and branch value) as the 2nd because it is a
> retransmission of the 2nd BYE, that is, a duplicate copy.  (Note that the
> network is permitted to deliver more than once a packet that has been sent,
> so the UAS (P-CSCF in this case) must be prepared to receive duplicate
> copies.)  When the UAS receives a duplicate of a request that it has already
> responded to, it does not re-process the request, but rather retransmits the
> response that it sent to the first copy of the request.  This is all
> detailed in RFC 3261.
>
> Dale
> _______________________________________________
> Sip-implementors mailing list
> [email protected]
> https://lists.cs.columbia.edu/cucslists/listinfo/sip-implementors
>
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