The number of valid frames received by this port from
its segment that were classified as belonging to this
VLAN. Note that a frame received on this port is
counted by this object if and only if it is for a
protocol being processed by the local forwarding process
for this VLAN. This object includes received bridge
management frames classified as belonging to this VLAN
(e.g., GMRP, but not GVRP or STP).