Connection admission control (CAC) for QoS differentiation in PMP IEEE 802.16 networks

Connection admission control (CAC) is an important element for quality of service (QoS) provisioning in wireless networks, such as IEEE 802.16 standard, which is also known as worldwide interoperability for microwave access (WiMAX). While the standard defines PHY and MAC requirements, CAC is left to the vendors to design and implement for service differentiation and QoS support. In this paper a Quadra-Threshold (QT) CAC scheme is proposed for IEEE 802.16 networks. The proposed CAC considers four different thresholds for the four connection types namely, UGS, ertPS, rtPS and nrtPS services. The QT scheme is used to prioritize each connection type for service differentiation and QoS support. A performance analysis model based on Markov chains is proposed and numerical results are presented to demonstrate the performance of the proposed scheme. The scheme when compared with complete partitioning scheme performs better in terms of blocking probability.