Dynamic Bandwidth Allocation for Multiple Traffic Classes in IEEE 802.16e WiMax Networks: A Petrinet Approach

摘要

Problem statement: WiMAX supports multiple types of traffic such as data, voice and video. Each flow requires a certain minimum bandwidth to achieve its QoS. Bandwidth allocation to traffic classes should be in such a way that fairness criteria is met with. We propose a dynamic bandwidth allocation mechanism to achieve fair and efficient allocation. Approach: We present a Generalized Stochastic Petri Net (GSPN) approach to model bandwidth allocation in Broadband Wireless Access (BWA) networks with multiple traffic classes. A dynamic weight assignment mechanism was proposed to enable fair bandwidth allocation among the competing traffic classes. Performance of the weight assignment mechanism was analytically evaluated using the GSPN model developed. Results: Results showed performance improvement in terms of mean delay and normalized throughput of traffic classes compared to existing mechanisms. Simulation was carried out for different traffic rates. Analytical results were validated using simulations. Conclusion: Performance of the proposed system is evaluated in terms of mean delay and normalized system throughput. The model developed is generic and can be extended to any wireless network with multiple traffic classes.