A string of octets containing one bit per VLAN in the management
domain. The first octet corresponds to VLANs with VlanIndex 1
through 8; the second octet to VLANs 9 through 16; etc. The most
significant bit of each octet corresponds to the lowest value
VlanIndex in that octet. If the bit correspond to a VLAN is set to
'1', then the VLAN is a configured transited VLAN on the local
device. (Default VLANs which must transit the local device are
always considered to be 'configured transited VLANs'.) Any attempt
to set a bit string which has: more bits set than the local device
can transit; or does not have all bits set corresponding to default
VLANs which must transit the device; or set any bits corresponding
to non-existant VLANs (VLANs whose IDs are not defined in the
management domain) will be completely rejected as an illegal
value.