Designs of Enhanced CAC with QoS Scheme for Efficient Resource Allocations on the IEEE 802.16 Network

Abstract

Five service types with different priorities are defined to meet the QoS needs for different users, there are UGS, ertPS, rtPS, nrtPS, and BE on the IEEE 802.16 network. First, SS has to send a connection request to BS before it is ready to transmit data. Then, SS can be allowed to transmit data while holding the allocated bandwidth from BS. Actually, BS utilizes CAC to identify whether there is enough bandwidth to serve the new connection requests from SS or not. When the numbers of SS are increasing, the more requests in bandwidth are higher. However, the CAC allocates bandwidth in sequence, so it may not satisfy the QoS demand. Based on conventional CAC, we propose an enhanced CAC with QoS scheme, called ECQ, to support efficient bandwidth allocation for connection requests of different service types on the IEEE 802.16 PMP mode. We use the QualNet tool to perform some experiments, and simulation results indicate that the proposed ECQ scheme can obtain a lower CBP of about 17.1% and higher Packet Delivery Ratio and Total Packets Received of about 19.16% and 29.2% compared to CAC, respectively. Finally, the goals of the proposed ECQ are to fix the CAC issue that resource is held by a specified service type and to achieve better performance than the CAC on the IEEE 802.16 network.