I've been attempting to get a grasp over all the multicast configurations that are available on our controllers and the behavior each one causes. I'm getting their slowly after reviewing the Roaming VRD ("chatty protocols") and other Airheads posts. Wanted to check if I'm on the right-track with each setting.
- Enable BCMC Optimization (VLAN Level) - Drops Broadcast/Multicast traffic originating from wireless clients to wired network - vice-versa. Applied at Control Plane level before any ACLs. Configured for locations where multicast is not needed?
- IGMP Snooping/Proxy and AirGroup - This one I'm struggling a bit on. I know IGMP Snooping is required/implemented on our wired network for multicast between our VLANs. Does AirGroup server as a replacement/alternative to IGMP Snooping?
- Drop Broadcast and Unknown Multicast (VAP Level) - From packet-captures can tell that the air isn't being flooded with multicast packets. Necessary for environments where some multicast users are necessary? Is this the situation where ACLs limiting "chatty protocols" would be required - or would this be handled by AirGroup?
Currently we have "BCMC Optimaztion" disabled, Drop Broadcast/Unknown Multicast enabled, and Airgroup disabled due to our authentication server being hit with with hundreds of Airgroup authentication requests that it started to affect ability of students to authenticate to the wireless network. I'm curious if by disabling AirGroup - we've inadvertently causing a flood of traffic to the wired network?
We've recently discovered that our uplink switch - a VSS - is being hammered by multicast originating from wireless clients - primarily - SSDP (239.255.255.250). I'm trying to understand the different between Unknown Multicast and what's considered a "Subscribed" client - since this setting was originally Drop Broadcast and Multicast.
Sorry if my questions are over-the-place/odd, I've been more familiar with the multicast settings on our old Meru Controllers. Thank you.