Hi, Prior to RFC 3264, presence of port=0 in the SDP was also used as an indication to put the call on hold.
>>>>> I have never seen such real time implementation (may be I have ignored if it exists). To place the call on hold, either use the media attribute 'SendOnly' (RFC 3264) or set the connection IP address to 0.0.0.0. (RFC 2543) If you use port=0 to place the call on hold, how will you play the MoH (Music on Hold) as port=0 will temporarily disconnect the media. As there is no specific option tag to indicate the support of RFC 3264, how should a party receiving port=0 interpret it? More specifically, should the receiving party delete the resources associated with this stream or just mark this as an inactive stream? >>>>> Why option tag is required to indicate the support of RFC 3264? Media should be disconnected (inactive) temporarily and resources should not be deleted permanently as you will be required to assign resources anytime during the session. As per RFC 3264, on receipt of port=0 for a media stream all resources associated with this media stream can be released. The slot occupied by this stream can be re-used later to add a new media stream. Can sending a valid port in a previously port zeroed stream reactivate that stream or is it equivalent to a new offer altogether? >>>>> I am not sure what is the difference between 'reactivate that stream' and 'equivalent to a new offer altogether'. As per RFC 3264 section 8.3.1, the port number for a stream MAY be changed. To do this, the offerer creates a new media description, with the port number in the m line different from the corresponding stream in the previous SDP. If only the port number is to be changed, the rest of the media stream description SHOULD remain unchanged. Regards, Umang Singh | Senior Lead | GlobalLogic Inc. Leaders in Software R&D Services ARGENTINA | CHILE | CHINA | GERMANY | INDIA | ISRAEL | UKRAINE | UK | USA Office: +91.120.406.2000 x <2691> www.globallogic.com ---------------------------------------------------------------------------- ---------------------------------------------------------------- With over 5,500 employees and innovation hubs on three continents, GlobalLogic allows both Fortune 100 leaders and emerging technology companies to tap a highly skilled talent pool to build innovative cloud, mobile, SaaS and social applications that provide a competitive edge in the global economy. For more information, visit: www.globallogic.com Disclaimer: <http://www.globallogic.com/email_disclaimer.txt> http://www.globallogic.com/email_disclaimer.txt _______________________________________________ Sip-implementors mailing list Sip-implementors@lists.cs.columbia.edu <https://lists.cs.columbia.edu/cucslists/listinfo/sip-implementors> https://lists.cs.columbia.edu/cucslists/listinfo/sip-implementors _______________________________________________ Sip-implementors mailing list Sip-implementors@lists.cs.columbia.edu https://lists.cs.columbia.edu/cucslists/listinfo/sip-implementors
