Abstract  In WiMax networks the routing and the scheduling are t ightly coupled. The routing and scheduling problem for WiMAX networks is different from 802.11 based mesh networks and can be designed and operated separately. Standard problems in wireless systems include Bandwidth allo cation and Connection Admission Control (CAC). In t his paper we design a joint routing, scheduling and admission control p rotocol for WiMax networks. In the adaptive schedul ing, packets are transmitted as per allotted slots from different pr iority of traffic classes adaptively, depending on the channel condition. A bandwidth estimation technique is combined with rou te discovery and route setup in order to find a best route. The admission control technique is based on the estimation of ban dwidth utilization of each traffic class, with the constraint that the delay requirement of real1time flows should be satisfied. The current available bandwidth is estimated for a ll the nodes and for the new incoming flows, it estimates the requested band width and decides to admit this new flow or not. By simulation results, we show that our proposed protocol achieves better thr oughput and channel utilization while reducing the blocking probability and delay.

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[19] Yu K., Wang X., Sun S., Zhang L., and Wu X., A Statistical Connection Admission Control Mechanism for Multiservice IEEE 802.16 Network, in Proceedings of the 69 th IEEE Vehicular Technology Conference , Barcelona, pp. 1-5, 2009. Raja Murali Prasad received his Engineering degree from the Institution of Engineers in 1989 and M.Tech degree from the Department of Electronics and Communications, Pondicherry Engineering College in 1993. He worked in various engineering colleges as faculty member. Presently, he is working as faculty member in the Department of Electronics and Communication Engineering, Vardhaman College of Engineering, Hyderabad. He is pursuing PhD at JNT University Anantapur. His research interests include digital communications, control systems and wireless communications. 94 The International Arab Journal of Information Techn ology, Vol. 10, No. 1, January 2013 Pentamsetty Satish Kumar received B.Tech degree in the Department of Electronics and Communication from Nagarjuna University in 1989 and M.Tech degree from Pondicherry University in 1992. He completed PhD degree from JNT University, Hyderabad in the year 2004. He has published 15 research papers at national and international level. Presently, he is working as a professor in the Department of Electronics and Communication Engineering, Vardhaman College of Engineering , Hyderabad. His research interests include multirate signal processing, image processing and wireless communications.