 24-bit Organizationally Unique Identifier (OUI) value administered by the IEEE Registration Authority [4]. There are three logical identifiers defined to recognize an active user and its associated connections as follows: Station Identifier (STID): the serving BS assigns a 12-bit STID to the MS during network entry or re-entry that uniquely identifies the MS within the coverage area of the serving BS. Each MS registered in the network is assigned an STID. Some specific STIDs are reserved, e.g., for broadcast and multicast and ranging. Temporary Station ID (TSTID): this logical identifier is used to protect the mapping between the STID and the MS MAC Address. A TSTID is assigned during the initial ranging process. During registration procedure, the BS assigns and transfers an STID to the MS using an encrypted registration response message. The serving BS discards the TSTID when the MS successfully completes the authentication procedures. Flow Identifier (FID): each MS connection is assigned a 4-bit FID that uniquely identifies the connections with the MS. The FIDs identify control and transport connections. The downlink and uplink transport FID values are chosen from 0b0011 to Ob1111 range. An FID that has been assigned to one DL/UL transport connection cannot be assigned to another DL/UL transport connection belonging to the same MS; therefore, the assigned FIDs in the downlink (or uplink) are unique for a particular terminal. However, an FID that has been used for a DL transport connection can be assigned to another UL transport connection associated with the same MS. Some specific FIDs may be pre-assigned. An FID value of 0b0000 designates a control FID (unicast control FID when PDU is allocated by unicast assignment A-MAP IE or broadcast control FID when PDU is allocated by broadcast assignment A-MAP IE). An FID value of 0b0001 indicates a MAC signaling header. Deregistration Identifier (DID): the DID uniquely identifies an idle-mode MS for paging purposes. Context Retention Identifier (CRID): if Deregistrati