An Efficient Connection Admission Control Mechanism for Ieee 802.16 Networks

In WiMAX network, Connection Admission Control (CAC) plays an important role in providing QoS guarantee [47]. The multimedia services are supported in IEEE 802.16 using connection admission control (CAC), packet scheduling, dynamic subcarrier assignment etc. It provides QoS guarantee between Base Station (BS) and Subscriber Station (SS) [21]. The CAC algorithm provides bandwidth guarantee and also ensures QoS guarantees to connections according to their service types [23].The connection admission control (CAC) mechanisms is not specified in the 802.16 standard. All real-time connections need CAC for guaranteeing any delay bounds or packet loss rates [48]. The minimization of blocking of connection requests and the QoS violation due to many admitted connection is the major concern of CAC [23]. The new connection is admitted only if the performance of existing traffic is not compromised by such admission. A new connection request is admitted or rejected based on availability of resources by the CAC. The new connections seeking for the admission may be of two types namely, handoff sessions and newly originated connections. In an admission control standpoint, the handoff sessions are often given higher priority over new sessions [47]. The radio resource management technique that plays a dominant role in the effective management of the resources is the admission control. In the wireless networks, the admission control reduces the call blocking probability by the optimized utilization of the available radio resources. The need of guaranteed QoS in the mobile