Dear Experts, This is a scenario. A send B a SDP message: m=video 7080 RTP/AVP 100 a=rtpmap:100 H264/90000 a=fmtp:100 profile-level-id = 420015; ... ... B can decode bitstream equal or below level 2.0, so B should reject this offer. But my concern is, on B's answer to A, can B request A to encode it's bitstream at a level equal or below 2.0, so that B can accept the offer? If this is possible, how should B reply? Or is it that the only options available to B is either to reject or accept the offer as a whole, and there is no room for negotiation? In addition, if B has profile_id of Baseline profile and constraint_set0_flag of 1 and level_idc of 2.1, B can accept the offer, right? Thank you very much. Warmest regards, Ryan Singapore ryandevil@xxxxxxxxx __________________________________________________ Do You Yahoo!? Tired of spam? Yahoo! Mail has the best spam protection around http://mail.yahoo.com _______________________________________________ Ietf@xxxxxxxx https://www1.ietf.org/mailman/listinfo/ietf