The VLAN ID attribute is only used when the enetEnableMultiService
flag has been set to true. The VLAN ID is a 12-bit VLAN ID and is
used when the OSAP is processing packets to differentiate between the
four service channels. This object must set if an access port supports
multiple services. VLAN ID is a 12-bit value and therefore the
value range is 0 to 4095. However value 0 is not a VLAN ID per
se, but rather a value indicating VLAN tagging is not used.