A novel framework for improving bandwidth utilization for VBR video delivery over widearea networks There are great challenges in streaming variablebitrate video over widearea networks due to the significant variation of network conditions. The utilization of the precious bandwidth of widearea networks is often low in such streaming systems. In this paper, we propose a novel framework to improve the bandwidth utilization from a new perspective. Instead of focusing on the performance of each single media stream, we aim to improve the overall bandwidth utilization for video streaming systems. We try to exploit the unoccupied bandwidth in ongoing streams and using it to deliver some prefetched data which can be used to facilitate future streaming. Preliminary results show that our mechanism has great potential to improve both the overall bandwidth utilization and the caching performance of the proxy servers in the streaming systems.

A more aggressive prefetching scheme for streaming media delivery over the internet Efficient delivery of streaming media content over the Internet becomes an important area of research as such content is rapidly gaining its popularity. Many research works studied this problem based on the clientproxyserver structure and proposed various mechanisms to address this problem such as proxy caching and prefetching. While the existing techniques can improve the performance of accesses to reused media objects, they are not so effective in reducing the startup delay for firsttime accessed objects. In this paper, we try to address this issue by proposing a more aggressive prefetching scheme to reduce the startup delay of firsttime accesses. In our proposed scheme, proxy servers aggressively prefetch media objects before they are requested. We make use of serversu0027 knowledge about access patterns to ensure the accuracy of prefetching, and we try to minimize the prefetched data size by prefetching only the initial segments of media objects. Results of tracedriven simulations show that our proposed prefetching scheme can effectively reduce the ratio of delayed requests by up to 38% with very marginal increase in traffic.