Joint Bandwidth Allocation and Connection Admission Control for Polling Services in IEEE 802.16 Broadband Wireless Networks

Although the medium access control (MAC) protocol and the physical layer are well defined in IEEE 802.16 standard, bandwidth allocation (BA) and connection admission control (CAC) remain as open research issues. In this paper, we present a joint adaptive bandwidth allocation and connection admission control method for real-time and non-real-time polling services in the IEEE 802.16-based broadband wireless networks which use adaptaive modulation and coding at the physical layer. This method is based on an optimization-based approach where the in-connection (i.e., packet-level) performances (i.e., delay and transmission rate for real-time and non-real-time polling services, respectively) are used as cost functions and decision criteria for allocating bandwidth and for accepting or blocking a new connection, respectively. A queueing model is used to analyze transmission delay and transmission rate under adaptive modulation and coding. Binary integer programming is used to obtain the solutions for the optimization formulation. Typical performance results demonstrate the superiority of the proposed scheme over traditional static and adaptive band-width allocation schemes.