Must i set an IP on Bridge for Multicast?
Or works multicast without any IP?
Must have the SetTop-Box an IP on it’s interface for receive Streams? I mean no multicast-IP. an normally IP…
IGMP is under IP, so yes, you need an IP to speak IGMP.
I believe the “no” above is based on an assumption that IGMP snooping is passive. To the extent that this is true, only the IGMP clients need IPs.
That said, you’ve also spoken of setting up an IGMP querier on the router, which makes it a client, so it needs an IP to send those queries from, else it cannot receive answers from active hosts still wanting a given multicast stream.
OK. Thanks. In my first post above, it’s a querier. But there are still switches between this and the client. Of course I don’t want to send the multicast traffic to every client port there. i.e. on the bridges of the switches IGMP-Snooping=yes and multicast-flood=no. Does this bridge on the switches between clients and router (querier) have to have an IP, or does IGMP snooping work completely without an extra IP on the bridge on the switches?
What you’re asking comes down to the question of the proper location of the querier. In a complex network, you want only one querier per LAN/VLAN, and it needs to be able to see all the relevant parts of the network.
You might not see the immediate application of this principle to your question, but to answer it, you have to ask further questions.
Do these “other switches” have multicast snooping enabled on them as well, or do they flood multicast?
Are you trying to set up multiple queriers, which may then get out of sync with each other?
Ideally, everything comes back to a network core, and it is here that you’re best-advised to put the querier. Everything else delegates the brains for handling multicast pruning to this core switch. In that ideal case, then no, none of the other switches need an IP for IGMP, since they just pass it through untouched.
If you’re trying to get clever, then the answer varies, and may Metcalfe be with you.
Do these “other switches” have multicast snooping enabled on them as well, or do they flood multicast?
No. No flood. snooping is enabled on this bridges.
Are you trying to set up multiple queriers, which may then get out of sync with each other?
only one Querier. In Top of the Net.
Ideally, everything comes back to a network core, and it is here that you’re best-advised to put the querier. Everything else delegates the brains for handling multicast pruning to this core switch. In that ideal case, then no, none of the other switches need an IP for IGMP, since they just pass it through untouched.
So is it. I just want to understand whether the subordinate switches need an IP so that they can do IGMP snooping correctly and not a multicast flood
Other than that, the Switches must be properly configured in order for the Multicast source and the IGMP clients to be able to successfully communicate with each other…
I have now continued the test. It works with a set-top box directly on the port of the switch. However, if I plug in a DSLAM and behind it an AVM FritzBox, it only works if I set “unknown broadcast-flood=yes” and “unknown multicast-flood=yes” in the bridge at the ingress and egress port. Shouldn’t that be over?
Is the other side of the DSLAM another subnet? If so, you have a routing barrier, so you need to set up PIM-SM to configure how multicast transits that barrier. The settings you speak of affect a single LAN only.
