[Live-devel] Multicast over RTSP

[Ross Finlayson]

> On Feb 10, 2021, at 10:17 AM, DJM-Avalesta <david.myers at avalesta.com> wrote:
> 
> Hi,
> 
> My live555-based RTSP video server is not working for multicast streams when accessed from VLC via an RTSP URL such as:
> 
> rtsp://10.100.10.71:554/Stream0
> 
> When I use wireshark to view the IGMP packets I notice that the following line is missing from the Session Description protocol returned to the caller:
> 
> Session Attribute (a): source-filter: incl IN IP4 224.180.10.71 10.100.10.71
> 
> Do I somehow have to enable IGMPv3 to get this to work?

No, your problem is simply that - when you called "ServerMediaSession::createNew()” to create your “ServerMediaSession” object - you didn’t set the (normally optional) “isSSM” parameter to True.  Because you want source-specific multicast, you need to set that parameter to True.

If you haven’t done so already, review the code for our “testH264VideoStreamer” demo application: “testProgs/testH264VideoStreamer.cpp”.

Also, although it’s probably not essential, I recommend that - instead of 224.180.10.71 - you use an IP multicast address in 232/8; that’s the range that’s been specifically reserved for source-specific multicast.  See RFC 4607:  https://tools.ietf.org/html/rfc4607

Finally, I recommend that, at first, you use our “openRTSP” command-line RTSP client - rather than a media player like VLC - to test your server; see http://www.live555.com/openRTSP/


Ross Finlayson
Live Networks, Inc.
http://www.live555.com/