>Few questions: >Is it realistic for a PRACK to carry an offer? Isnt PRACK usually supposed >to carry an answer to a 183 OFFER? In what scenarios can a PRACK actually >carry an OFFER? ( only if INVITE had no offer and one recieved a 180? )
If INVITE has an offer and it is answered in 1xx-rel, PRACK for that 1xx-rel can contain a new offer. >Also if an INVITE carried an offer and the 183 carried back an answer, >wouldnt it be wrong for a PRACK to send back another OFFER in its SDP? Isnt >UPDATE used to do that kind of mid dialog change? No, it is not incorrect for the PRACK to carry a new offer. However I see only one scenario in which PRACK can carry an offer. Invite has an offer, it is answered with 1xx-rel. PRACK **for this** 1xx-rel can contain another offer. Subsequent 1xx-rels(also 200) should not **include** the SDP and PRACKs for those 1xx-rels shouldn't contain offer. UPDATE is the right way in those cases. >Also an Offer can be carried be any message in a transaction only if its an >initial offer right? Like INVITE already contained an offer then any >subsequent request in that transaction cannot carry another OFFER right? ( >besdies UPDATE). Per transaction one offer/answer is allowed. INVITE transaction can have one offer/answer. INVITE offer - 1xx-rel or 2xx with answer INVITE w/o offer - first reliable response contains offer (1xx-rel or 2xx) - answer in ACK. PARCK and UPDATE requests form seperate transactions and they are requests within the dialog. Your statement *subsequent requests with in that transaction* is not correct. If you mean early dialog by that, only PRACK and UPDATE are allowed requests which can contain offer during early dialog. -Ramakrishna Thanks Manpreet _______________________________________________ Sip-implementors mailing list [email protected] http://lists.cs.columbia.edu/mailman/listinfo/sip-implementors <http://lists.cs.columbia.edu/mailman/listinfo/sip-implementors> Confidentiality Notice 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 confidential or privileged information. If you are not the intended recipient, please notify the sender at Wipro or [EMAIL PROTECTED] immediately and destroy all copies of this message and any attachments. _______________________________________________ Sip-implementors mailing list [email protected] http://lists.cs.columbia.edu/mailman/listinfo/sip-implementors
