The Filtering Database used by this VLAN. This is one
of the dot1qFdbId values in the dot1qFdbTable. This
value is allocated automatically by the device whenever
the VLAN is created: either dynamically by GVRP, or by
management, in dot1qVlanStaticTable. Allocation of this
value follows the learning constraints defined for this
VLAN in dot1qLearningConstraintsTable.