In my opinion : - you should use cancel as long as the the 200 OK on the invite has not come back. - secondly, cancel is hop by hop. Hence I assume that when you use a proxy or chain of proxies you can't be sure that the bye will arrive at its destination. Cancel will go as far as the invite is in the chain.
Cheers, Johan. From: Jan Bollen [mailto:jan.bol...@scarlet.be] Sent: dinsdag 8 oktober 2013 9:15 To: sip-implementors@lists.cs.columbia.edu Subject: Re: [Sip-implementors] Terminating early dialog with BYE. - Email found in subject Hello, The question is: where is the "pending" request in the presented scenario with the BYE sent in a early dialogue. The same RFC also states: "The notion of "hanging up" is not well defined within SIP. It is specific to a particular, albeit common, user interface. Typically, when the user hangs up, it indicates a desire to terminate the attempt to establish a session, and to terminate any sessions already created. For the caller's UA, this would imply a CANCEL request if the initial INVITE has not generated a final response, and a BYE to all confirmed dialogs after a final response." So I wonder under what circumstances a BYE would be sent instead of a CANCEL when the INVITE has not resulted in a session yet. Kind regards, Jan On 7/10/2013 13:30, Preksha Gupta wrote: Hi Pravin It is recommended for UAS to send 487 for pending requests in such scenarios. Refer Section 15.1.2 of RFC 3261: " The UAS MUST still respond to any pending requests received for that dialog. It is RECOMMENDED that a 487 (Request Terminated) response be generated to those pending requests." Regards Preksha <http://tools.ietf.org/html/rfc3261#section-15.1.2><http://tools.ietf.org/html/rfc3261#section-15.1.2> On Mon, Oct 7, 2013 at 4:49 PM, Pravin Kumar <pravink...@gmail.com><mailto:pravink...@gmail.com> wrote: According to RFC 3261: Early Dialog can be terminate sending by BYE or CANCEL for UAC side. In case of CANCEL we should send 487 for INVITE UAC UAS ---------INVITE---------------------> < ---------180---------------------- ----------CANCEL----------- > < ---------200 CANCEL------- < -----------487 --------------- ------------ACK 487-----------> But in the of BYE: UAC UAS -------INVITE-----------------> < ---------180----------------- ----------BYE ---------------- > < ---------200 BYE ----------- <--(what should be send)----- (503 or 487) ------------ACK -------------> So in the case of sending BYE by UAC , UAS should send 503 or 487 for INVITE. Thanks, Pravin _______________________________________________ Sip-implementors mailing list Sip-implementors@lists.cs.columbia.edu<mailto:Sip-implementors@lists.cs.columbia.edu> https://lists.cs.columbia.edu/cucslists/listinfo/sip-implementors ________________________________ No virus found in this message. Checked by AVG - www.avg.com<http://www.avg.com> Version: 2014.0.4142 / Virus Database: 3604/6729 - Release Date: 10/07/13 _______________________________________________ Sip-implementors mailing list Sip-implementors@lists.cs.columbia.edu https://lists.cs.columbia.edu/cucslists/listinfo/sip-implementors
