yes, you need to include the 100rel otion tag if you want PRACK. from rfc3262...
The UAS MUST send any non-100 provisional response reliably if the initial request contained a Require header field with the option tag 100rel. If the UAS is unwilling to do so, it MUST reject the initial request with a 420 (Bad Extension) and include an Unsupported header field containing the option tag 100rel. If the request did not include either a Supported or Require header field indicating this feature, the UAS MUST NOT send the provisional response reliably. Regards, Attila -----Original Message----- From: [EMAIL PROTECTED] [mailto:[EMAIL PROTECTED] Behalf Of Benjamin Jacob Sent: 11 December 2006 04:40 To: [email protected] Subject: Re: [Sip-implementors] PRACK Doubt Does the UAS force the UAC to send PRACKs using 100rel in the 18x response? If 100rel is not present, will/shud the UAC send a PRACK? cheerz - Ben. Attila Sipos wrote: >Provisional responses (typically 18x) without using PRACK >are not reliable. > >So if the 18x is carrying SDP information then if the 18x >didn't get through then early media (which could contain >an important announcement) would fail. > >PRACK makes sure that the 18x is reliable. >The 18x gets sent and then the sender waits for a PRACK request. >If, after a while the PRACK isn't received, the 18x is retransmitted. >The retransmissions of the 18x message try to make sure that >the early media succeeds. > >Regards, > >Attila > > > >-----Original Message----- >From: [EMAIL PROTECTED] >[mailto:[EMAIL PROTECTED] Behalf Of >Nithyakumar.R >Sent: 09 December 2006 08:00 >To: [email protected] >Subject: [Sip-implementors] PRACK Doubt > > > > > Hi, > > > > What was the use of PRACK??? ..In what situation this msg will be >used..Please clear my doubt. > > > > > > > >With Regards, > >Nithyakumar.R > > > > > > > >This e-mail and attachments contain confidential information from HUAWEI, >which is intended only for the person or entity whose address is listed >above. Any use of the information contained herein in any way (including, >but not limited to, total or partial disclosure, reproduction, or >dissemination) by persons other than the intended recipient's) is >prohibited. If you receive this e-mail in error, please notify the sender by >phone or email immediately and delete it > > > > >_______________________________________________ >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 _______________________________________________ Sip-implementors mailing list [email protected] https://lists.cs.columbia.edu/cucslists/listinfo/sip-implementors
