Alex, SDP in 18X and 200 OK must be same from the same endpoint (to-tag). If endpoint has sent SDP in 18X and it's confirmed by UAS ( using PRACK ), UAC does not need to send SDP in 200 OK ( it's optional to send SDP in 200 OK in that case).
-----Original Message----- From: [email protected] [mailto:[email protected]] On Behalf Of Alex Balashov Sent: Thursday, June 10, 2010 9:06 AM To: [email protected] Subject: [Sip-implementors] 18x+SDP then 200 OK+SDP Greetings, If in a typical INVITE transaction to set up a session there can be only one SDP offer and one answer, and the first answer is final, then why the practice of sending 18x+SDP and then sending the answer again in 200 OK? Thanks, -- Alex Balashov - Principal Evariste Systems LLC 1170 Peachtree Street 12th Floor, Suite 1200 Atlanta, GA 30309 Tel: +1-678-954-0670 Fax: +1-404-961-1892 Web: http://www.evaristesys.com/ _______________________________________________ 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
