A PRIORITIZED ADAPTIVE BANDWIDTH RESERVATION SCHEME FOR REAL-TIME WIRELESS NETWORKS

Abstract

In the next generation high-speed wireless networks, it is important to provide quality-of-service (QoS) gurantees as they are expected to support multimedia applications. Recently an admission control scheme based on adaptive bandwidth reservation to provide QoS gurantees for multimedia traffic carried in high speed wireless cellular networks was proposed. This scheme allocates bandwidth to a connection in the cell where the connection request originates and reserves bandwidth in all neighboring cells. When a user moves to a new cell and a handoff occurs, bandwidth is allocated in the new cell, reserved bandwidth in more distant cells is released. The amount of bandwidth to reserve is dynamically adjusted, reflecting the currrent network conditions. In this dissertation, first both the existing and recently proposed schemes are compared and togeather with it a new scheme is proposed which prioritizes the new connection requests. Prioritized scheme has been compared to the recently proposed scheme. The performance of all the schemes is compared througi simulations of realistic cellular environments. The simulated network consistsJof a large number of cells, mobile users with various movement patterns are assumed, and a variety of multimedia applications (e.g. audio phone, video conference, video on demand, file transfer, etc.) is considered. It is shown that the proposed scheme provides small iii handoff dropping probability (i.e. the probability that handoff connections are dropped due to a lack of bandwidth) and achieves high bandwidth utilization. The implementation is done in C language on the TATA ELXSI RISC system under UNIX environemnt.