This read-only counter tallies frames the BUS has forwarded that were multicast frames. This isolates genuinely multicast or broadcast traffic, as opposed to the flooded-unicast case in busOutFwdUcastFrms, being distributed by the BUS to every LEC client on the emulated LAN, so it best reflects actual broadcast application traffic volume, such as address-resolution requests, across the ELAN. A sudden sustained increase here, distinct from the flooded-unicast counter, would point to genuine broadcast traffic, such as a broadcast storm from a misbehaving client, rather than clients simply failing to resolve direct VCs.