-11, the BS transmits the PGID_Info MAC control message at a predetermined location in the paging listening interval in order to advertise the paging CHAPTER 4 IEEE 802.16m System Operation and State Diagrams Superframe = 20 ms -Radio Frame = 5 ms Primary ISuperframe Header Secondary Superframe Header Advanced MAPs (Control Channels) PGID_Info Secondary Advanced Preamble Subframe FIGURE 4-11 Transmission of PGID_Info MAC control messages [2] groups that are supported by the BS or to which the BS is associated. The PGID_Info - is transmitted by the BS regardless of any notifications for the mobile stations. The BS transmits the PGID_Info immediately after the superframe header and advanced MAPs in the first subframe of the superframe and during mobile station's paging listening interval, as shown in Figure 4-11. The PGID_Info is transmitted before any paging advertisement message in the superframe. Using the PGID_Info, the MS can determine whether it is located in the same paging group as its preferred BS or the paging group that it most recently belonged to. If none of the PGIDs to which the MS belongs are detected, the MS determines that the set of paging groups has changed and performs Idle Mode location update. The MS monitors a predetermined frame for paging message. The predetermined frame Npaging-frame for MS is given as Npaging-frame = MS Deregistration Identifier mod m (m = 1, 2, 3, or 4). The MS or the serving BS can initiate the Idle State transition using procedures defined in IEEE 802.16m [2] (or alternatively corresponding procedures in reference [1] for the legacy systems). In order to reduce signaling overhead and provide location privacy, a temporary identifier is assigned to uniquely identify the idle mode mobile stations in a particular paging group. The mobile station's temporary identifier remains valid as long as the MS stays in the same paging group. The temporary identifier assignment may happen during Idle State entry or during location update due to paging group 4.1 IEEE 802. 16m mobile s