One goal was to keep layer 2 multicast network off wireless where possible. Mikrotik's don't do IGMP snooping (until very recently). The wireless backbone had t

One goal was to keep layer 2 multicast network off wireless where possible. Mikrotik's don't do IGMP snooping (until very recently). The wireless backbone had to support multi-networked traffic of course, but local traffic (between a couple of devices in one room) could be kept off the link