[Live-devel] A problem: receiving data from several multicast groups, while joined only one

[Ross Finlayson]

>I have two processes - one streaming UDP data to specific multicast group
>(streamer), the second - receiving data from the same group (receiver).
>On the streamer side I create Groupsock object with specific multicast IP, and
>start to stream the data.
>On the recorder side - I'm receiving the data for the multicast group with
>this IP. 
>But the problem is that the receiver gets the data for even it is joined to
>the different multicast group. It looks like I cannot differentiate the
>streams by group.

This is an OS problem.  Some OSs (e.g., some versions of Linux) do 
not distinguish between incoming packets sent to different multicast 
group addresses, but with the same port number.

The solution is to use different port numbers, as well as different 
multicast groups.

>My question is: Is it correct to bind the receiving side socket to the same
>address as multicast group address?

No.  "ReceivingInterfaceAddr" - if not set to "INADDR_ANY" must be 
set to the unicast IP address of one of your network interfaces, not 
to a multicast address.
-- 

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