The bandwidth allocation by queue length (BA-QL) for WiMAX network

Worldwide Interoperability for Microwave Access (WiMAX) is a broadband wireless access (BWA) technology. It provides high data rate and multimedia service. It also supports Quality of Service (QoS) for various types of application. In this network, it is important to allocate appropriate resource to different class of service to guarantee the delay of real-time service and avoid the starvation of non real-time service. In IEEE 802.16, this part is remained opened to be explored. There is a connection admission control (CAC) mechanism in this network to allow a connection reserving bandwidth beforehand. However, a good prediction of the required bandwidth is not easy. A reserved bandwidth may not always meet its load. Thus, an algorithm adaptive to the load is proposed here. In this paper, a reserved bandwidth is allocated to each connection in the first stage. Then, two possible weighted fair queue (WFQ) algorithms are proposed. In the first one, the weight is decided by the left queue length of the connection. In the second one, the weight is decided by the left queue length and class of the connection. In this stage, the allocation will continue until the bandwidth of the frame is exhausted or all packets in the queue have been scheduled. The simulation will be done and compared with the round robin algorithm for both methods. The results show these algorithms can adapt to the load of the connection.