A string of octets containing one bit per VLAN in the management domain on this port. The first octet corresponds to VLANs with VlanIndexOrZero values of 0 through 7; the second octet to VLANs 8 through 15; etc. The most significant bit of each octet corresponds to the lowest value VlanIndexOrZero in that octet. A bit can only be set to '1' when the bit is corresponding to a VLAN of Private VLAN isolated, community type which has already been associated with a primary VLAN. Note that if the length of this string is less than 128 octets, any 'missing' octets are assumed to contain the value zero. An NMS may omit any zero-valued octets from the end of this string in order to reduce SetPDU size, and the agent may also omit zero-valued trailing octets, to reduce the size of GetResponse PDUs.