[streaming] Missing RTCP packets

[Rémi Denis-Courmont]

Le Wednesday 14 May 2008 20:26:27 Javier Gálvez Guerrero, vous avez écrit :
> I am trying to track RTP and RTCP packets in a streaming service based in
> VLC through the telnet interface, generating VOD and broadcast streams. In
> order to catch the packets I use Wireshark. Both server and client sides
> run over Linux 2.6.24-16.
>
> The VLC server configuration is this:
>
> #VOD
>
> new garbage vod enabled
> setup garbage input
> /media/MOTHER/diptvServerLinux32/contents/rock_GARBAGE.mpg
>
> new offspring vod enabled
> setup offspring input
> /media/MOTHER/diptvServerLinux32/contents/punk_OFFSPRING.mpg
>
>
> #BROADCAST
>
> new br broadcast enabled loop
> setup br input /media/MOTHER/diptvServerLinux32/contents/metal_KORN.mpg
> setup br output #rtp{mux=ts,dst=239.255.1.2,name="Channel"}
>
> control br play
>
>
> So, I have two problems:
>
> 1. VOD: Client side sends RTCP packets to the tcpmux port (1) and server
> side answers with an ICMP packet (Destination unreachable - Port
> unreachable). AFAIK RTCP packets should be sent (in default mode) to the
> video/audio stream port + 1, shouldn't they? What has to be done in order
> to keep RTCP packets sent properly?

> 2. BROADCAST: There are no RTCP packets at all. Again, AFAIK, RTCP packets
> must be sent both in unicast and multicast streams, so, what is happening?

As is, it looks like a set of bugs in liblive555, but that seems surprising.

Could we have a dump of the RTSP requests & responses?

> By the way, a question regarding the RTCP associated procedure. Should the
> server side send any RTCP packet to its clients or it only receives the
> ones sent by its clients and manages to offer a better quality stream?

The server should send RTCP sender reports. That's implemented in vlc 0.9.0, 
at least in broadcast mode.

-- 
Rémi Denis-Courmont
http://www.remlab.net/