[Live-devel] VLC: RTCP bug?

[Ross Finlayson]

>m=video 40000 RTP/AVP 96
>
>VLC assumes that it should send RTCP Receiver Reports to UDP port 40001.

That's correct.  Note that having a client "read a SDP file" (rather than 
opening a "rtsp://" URL) usually makes sense only for multicast sessions, 
because that's usually the only time you know - in advance - what IP 
address and port RTCP reports should be sent to.  For multicast sessions, 
all parties use the same IP address and port number for sending and 
receiving RTCP packets.

There's no "bug" here.

>I think the problem here is that VLC is not doing any RTSP, so without a
>SETUP it has no way to known in advance which RTCP port the video server
>will use.

That's correct.  (See above.)

>If you think that the video server should use UDP port 40001 as a source
>for RTCP, as VLC currently assumes, could you please give me some more
>information about that (RFC or links)?

See sections 3.1 and 4.1 of the SDP specification 
<http://www.ietf.org/internet-drafts/draft-ietf-mmusic-sdp-new-16.txt>, 
which describes how SDP is used for multicast session announcements.


	Ross Finlayson
	LIVE.COM
	<http://www.live.com/>