Caching Strategies in Transcoding-Enabled Proxy Systems for Streaming Media Distribution Networks

B. Shen, S.-J. Lee, S. Basu
2004 IEEE transactions on multimedia  
With the wide availability of high-speed network access, we are experiencing high quality streaming media delivery over the Internet. The emergence of ubiquitous computing enables mobile users to access the Internet with their laptops, PDAs, or even cell phones. When nomadic users connect to the network via wireless links or phone lines, high quality video transfer can be problematic due to long delay or size mismatch between the application display and the screen. Our proposed solution to this
more » ... problem is to enable network proxies with the transcoding capability, and hence provide different, appropriate video quality to different network environment. The proxies in our transcoding-enabled caching (TeC) system perform transcoding as well as caching for efficient rich media delivery to heterogeneous network users. This design choice allows us to perform content adaptation at the network edges. We propose three different TeC caching strategies. We describe each algorithm and discuss its merits and shortcomings. We also study how the user access pattern affects the performance of TeC caching algorithms and compare them with other approaches. We evaluate TeC performance by conducting two types of simulation. Our first experiment uses synthesized traces while the other uses real traces derived from an enterprise media server logs. The results indicate that compared with the traditional network caches, with marginal transcoding load, TeC improves the cache effectiveness, decreases the user-perceived latency, and reduces the traffic between the proxy and the content origin server. Index Terms-proxy caching, streaming media, video transcoding, network measurements, streaming in wireless networks, streaming media distribution IP Network Transcoder Input Buffer Output ¡ Buffer server link ¢ 128Kbps Caching £ System ¤ RTP/RTSP Client RTP/RTSP Server origin ¥ server ¢ desk ¦ top § lap ¨ t op § cell © phone 56Kbps client link ©
doi:10.1109/tmm.2003.822791 fatcat:bce6qrivanbqznezxsdnrxksvq