[sr-dev] ICE=force_relay tests between two baresips

[Richard Fuchs]

On 05/01/14 06:52, Juha Heinanen wrote:
> Richard Fuchs writes:
> 
>>> if a=rtcp:<port> did not exist in incoming sdp, there is no need for
>>> rtpengine to add it, because then, by default, rtcp port is one larger
>>> than rtp port.
>>
>> ICE mandates that the a=rtcp attribute is present, even if the RTCP port
>> is the default one.
> 
> I did check ice rfc 5245 and didn't find such requirement.  Word "rtcp"
> does not exist in the rfc and its ice sdp example does not include rtcp
> attribute:
> 

Section 4.3, 6th paragraph:

   The default candidates are added to the SDP as the default
   destination for media.  For streams based on RTP, this is done by
   placing the IP address and port of the RTP candidate into the c and m
   lines, respectively.  If the agent is utilizing RTCP, it MUST encode
   the RTCP candidate using the a=rtcp attribute as defined in RFC 3605
   [RFC3605].  If RTCP is not in use, the agent MUST signal that using
   b=RS:0 and b=RR:0 as defined in RFC 3556 [RFC3556].

The sample SDP doesn't include it because it has RTCP disabled.

cheers

-------------- next part --------------
A non-text attachment was scrubbed...
Name: signature.asc
Type: application/pgp-signature
Size: 880 bytes
Desc: OpenPGP digital signature
URL: <http://lists.sip-router.org/pipermail/sr-dev/attachments/20140501/0d313f83/attachment.pgp>