You are right. UAS has only 2 options to terminate the call depending on the state of the call.
1. Reject the call with failure response (if call is not been accepted) 2. Reject the call with BYE message (if call is accepted) In NO case, UAS can send the CANCEL request to terminate the call. Regards, Nataraju A B -----Original Message----- From: [EMAIL PROTECTED] [mailto:[EMAIL PROTECTED] On Behalf Of Jagan Mohan Sent: Monday, November 19, 2007 11:54 AM To: Vishal Mathur Cc: [email protected] Subject: Re: [Sip-implementors] UAS sending a CANCEL Hi All, Thanks for the answers. It was finally agreed that UAS should not send a CANCEL in this case. Regards, Jagan On 11/15/07, Vishal Mathur <[EMAIL PROTECTED]> wrote: > > Hi Jagan, > > I think UAS behavior is not correct as per SIP RFC. > In no case a UAS (US which receive calls) can send a Cancel. It can > only send Responses. > > Can you provide us the logs (tcpdump) of UDP messages send by UAS and > Gateway? Also give us some more description regarding the UAS and > Media Gateway device (company, model and version). Probably it might > be a bug / issue in UAS SIP stack code. > > PS: Try the same case with other device and contact vendor of UAS > regarding this issue. They might has new version of firmware already. > > Regards, > > Vishal Mathur > Jabber ID: [EMAIL PROTECTED] > Symantec Corporation > www.symantec.com > _________________________________ > Office: +91-20-66067655 > > -----Original Message----- > From: [EMAIL PROTECTED] > [mailto:[EMAIL PROTECTED] On Behalf Of > Jagan Mohan > Sent: Wednesday, November 14, 2007 5:35 PM > To: [email protected] > Subject: [Sip-implementors] UAS sending a CANCEL > > Hi All, > > I have the following call flow: > > PSTN===Media Gateway-----UAS > > Call flow is made from PSTN phone to UAS. > > Media --------------UAS > Gateway > > INVITE--------> > <--------100 Trying > <--------180 Ringing > > At this point, can UAS send a CANCEL to the media gateway? > > From the discussion in various mailing lists, I understand that UAS > can not send a CANCEL request in this scenario. It can send a 4xx/6xx > > But, I could not find any RFC which talks about this. Could any one > please provide info. on the RFC which talks about the above scenario? > > TIA, > Jagan > _______________________________________________ > Sip-implementors mailing list > [email protected] > https://lists.cs.columbia.edu/cucslists/listinfo/sip-implementors > _______________________________________________ Sip-implementors mailing list [email protected] https://lists.cs.columbia.edu/cucslists/listinfo/sip-implementors The information contained in this electronic message and any attachments to this message are intended for the exclusive use of the addressee(s) and may contain proprietary, confidential or privileged information. If you are not the intended recipient, you should not disseminate, distribute or copy this e-mail. Please notify the sender immediately and destroy all copies of this message and any attachments. WARNING: Computer viruses can be transmitted via email. The recipient should check this email and any attachments for the presence of viruses. The company accepts no liability for any damage caused by any virus transmitted by this email. www.wipro.com _______________________________________________ Sip-implementors mailing list [email protected] https://lists.cs.columbia.edu/cucslists/listinfo/sip-implementors
