VlanIdOrNone
The VLAN-ID that uniquely identifies a specific VLAN, or no VLAN. The special value of zero is used to indicate that no VLAN-ID is present or used. This can be used in any situation where an object or a table entry must refer either to a specific VLAN, or to no VLAN. Note that a MIB object that is defined using this TEXTUAL-CONVENTION should clarify the meaning of 'no VLAN' (i.e., the special value 0).