Question about IP multicasting.
 

Hi Guys,

We have a little lab here at work where we're trying to setup a multicast stream to a STB using VLC. The current setup is as below:

VLC is running on RHEL 4 and is streaming to the multicast address: 239.0.255.1. The server is then connected via a cross-over cable to the recieving STB with the IP address 192.168.100.100. The STB has the IP address: 192.168.100.101.

The STB isn't picking up the stream when VLC is set to broadcast to the multicast address but it works fine when the stream is set to unicast to 192.168.100.101 (STB).

Is there a 'universal' multicast address I could stream to so the STB will pick up the stream without the use of IGMP/routing etc?

Also the point of the lab is to test the STBs without configuring them. :scratch:

Firstly, lets not get our terminology mixed up. Broadcasting is entirely different from multicasting, you do not broadcast to a multicast address, you multicast to it.

Secondly, Your question seems a bit confused. You say you are connecting the STB to the server back-to-back via a crossover cable, so there is no routing to consider. And IGMP is a mechanism to allow Hosts to register with routers that may be able to supply multicast streams. If there is no router in your test network then IGMP is not relevant. I assume that by STB you mean Set Top Box; you do not need the STB to "join" a multicast group to allow the sender to send. Senders just do. If there is no multicast routing network between sender and receiver, and no switch either, then the problem you are looking at is that either the sender isn't sending what it says it is, or the receiver isn't receiving what it should be.

I would recommend running wireshark at both ends to see whats going on. If this is not an option on the STB then replace it with another PC also running VLC. Once you can send and receive a stream and see it on the sniffers, then put the STB back. You will at least be working in the knowledge that the sender is sending as it should, then any problem you have is the STB misbehaving.