A dynamic and adaptive bandwidth management scheme for QoS support in wireless multimedia networks

In this paper, a dynamic and adaptive bandwidth management scheme is proposed to provide as satisfactory quality-of-service (QoS) guarantee as possible for wireless multimedia services under variable traffic conditions. Under the highly variable wireless environment, the existing bandwidth management schemes result in more frequent quality changes for active flows than necessary, which are undesirable and intolerant to multimedia real-time applications. The proposed scheme is designed to provide high bandwidth utilization efficiency and low call blocking probability with minimum QoS fluctuation. In order to minimize the impact of bandwidth change for the QoS of existing flows, a controlled bandwidth degradation algorithm is performed when the free bandwidth in a cell isn't enough to admit a new flow. Compared with existing schemes, our scheme reduces the probability of frequent quality changes and provides more satisfactory services for higher priority flows. The performance analysis has shown that, under the same network load, our proposed scheme outperforms existing ones with lower QoS degradation probability.