[prev in list] [next in list] [prev in thread] [next in thread] 

List:       sip-implementors
Subject:    RE: [Sip-implementors] Re: About ACK request
From:       "vimal srivastava" <vimalsrivastava () hotmail ! com>
Date:       2005-09-26 8:07:09
Message-ID: BAY101-F36F20341C3F08C76F61461BE8B0 () phx ! gbl
[Download RAW message or body]

ack is part of all non-2xx final response for Invite request.
cheers



From: Jayesh <jayesha@dlink.co.in>
To: sip-implementors@cs.columbia.edu
CC: y030729@njupt.edu.cn
Subject: [Sip-implementors] Re: About ACK request
Date: 26 Sep 2005 08:49:46 +0530



 > HI Zhenyu,

The main reason for which ACK is sent is to ensure that the
Invite-Response is reached the destination successfully. Hence it makes
sense that th application will never be knowing about ACK. Thus upon
reception of a Response ACK could be sent directly from transaction
reducing burden from your application.
But as the Success Response to Invite (2XX) may contain SDP ,hence
should be processed at application layer.
That is why behavior of ACK is like that.
Additionally all transactions are Request-Response based and there is no
response for ACK, thats why there is no transaction for ACK.

I hope this clears your doubts.


Regards,

Jayesh A Sangpal
D-Link (India) Ltd
Bangalore-560068
India.


 >
 > ______________________________________________________________________
 >
 >
 > From: Zhenyu Wu <y030729@njupt.edu.cn>
 > To: sip-implementors@cs.columbia.edu
 > Subject: [Sip-implementors] About ACK request!
 > Date: 25 Sep 2005 09:23:01 +0800
 >
 > Hello,
 >
 > We know, there is no transaction for ACK request. But in section 13.1 of 
RFC3261,
 > there is such a statement: "For final responses between 300 and 699, the 
ACK
 > processing is done in the transaction layer and follows one set of rules 
(See
 > Section 17).  For 2xx responses, the ACK is generated by the UAC core".
 >
 > why the ACK processing is done in the transaction layer, as there is no
 > transaction for ACK request?
 >
 > Thanks,
 >
 > Zhenyu
 >


_______________________________________________
Sip-implementors mailing list
Sip-implementors@cs.columbia.edu
http://lists.cs.columbia.edu/mailman/listinfo/sip-implementors



[prev in list] [next in list] [prev in thread] [next in thread]