[sr-dev] mediaproxy-ng Got LOOKUP, but no usable callstreams found

Juha Heinanen jh at tutpro.com
Mon Oct 28 16:59:16 CET 2013


Richard Fuchs writes:

> Possibly it's because of the non-standard RTCP port in the answer.
> Technically this is supported but the implementation is more of a hack
> than anything else for the time being.

looks like the rtpc port number in 200 ok is not "non-standard"
anymore.  from rfc 3605 dated october 2003:

   The SIP messages use the encoding defined in SDP [RFC2327] to
   describe the IP addresses and TCP or UDP ports used by the various
   media.  Audio and video are typically sent using RTP [RFC3550], which
   requires two UDP ports, one for the media and one for the control
   protocol (RTCP).  SDP carries only one port number per media, and
   states that "other ports used by the media application (such as the
   RTCP port) should be derived algorithmically from the base media
   port."  RTCP port numbers were necessarily derived from the base
   media port in older versions of RTP (such as [RFC1889]), but now that
   this restriction has been lifted, there is a need to specify RTCP
   ports explicitly in SDP.

-- juha



More information about the sr-dev mailing list