Wireless Video Streaming QoS Guarantees Based on Virtual Leaky Bucket

With recent rapid advances in wireless communication and networking, the demand for wireless video streaming is exploding. Unlike data streaming, video streaming is much more challenging due to unique characteristics such as bursty flow, stringent delay bound, and selective loss tolerance. Under the dynamic nature of wireless channels, wireless video streaming is virtually impossible to achieve deterministic quality-of-service (QoS) guarantee. Recent development in statistical QoS guarantees has shown great potential for wireless video streaming. However, in the case of statistical QoS guarantee, loss of data due to queue length bound violation or delay violation is often inevitable. Because of unequal importance of video data stream and their inherent dependency, different loss patterns will result in distinctive loss impact. It is critical to design an appropriate scheme to control the loss of video data in such a way that it will minimize the impact of such loss. We develop in this research a prioritized packet dropping scheme based on virtual leaky bucket to control the delivery of video streams. We have carried out analysis based on effective capacity, effective bandwidth, and virtual leaky bucket to demonstrate the potential of the proposed scheme. Preliminary results obtained from simulations show that an improved performance in QoS guarantees can be achieved for wireless video streaming.