o the traffic load, and also includes the functions of load control (load balancing), admission control, and interference control; 3.2 The IEEE 802.1 16m protocol structure Network Layer Management SAP and Control SAP CS-SAP Relay Radio Resource Location System configuration Functions Management management Convergence Sublayer management Mobility Idle Mode Multi-Carrier Management Management Classification Security Service flow and Network-entry Self Organization Connection management Header Management Management suppression Radio Resource Control and Management (RRCM) MAC SAP Fragmentation/Packing Medium Access Control (MAC) Multi Radio Sleep Mode Scheduling and Coexistence Management Resource Multiplexing MAC PDU formation PHYControl Data Forwarding Interference Link Adaptation Control Encryption Management Ranging (CQI, HARQ, power Signaling control) Control-Plane Data-Plane PHY Protocol (FEC Coding, Signal Mapping, Modulation, MIMO processing, etc.) Physical Layer FIGURE 3-12 The IEEE 802. 16m general protocol stack [12] Mobility management block scans neighbor BSs and decides whether MS should perform handover operation; Network-entry management block controls initialization and access procedures and generates management messages during initialization and access procedures; Location management block supports location based service (LBS), generates messages including the LBS information, and manages location update operation during idle mode; Idle mode management block controls idle mode operation, and generates the paging advertisement message based on paging message from paging controller in the core network; Security management block performs key management for secure communication. Using managed key, traffic encryption/decryption and authentication are performed; System configuration management block manages system configuration parameters, and generates broadcast control messages such as superframe headers; CHAPTER 3 IEEE 802. 16m Reference Model and Protocol Structure Multicast and broadcast service (MB