Hybrid Segment-Based Transcoding Proxy Caching of Multimedia Streams

Streaming media has contributed to a significant amount of todaypsilas Internet traffic. Like traditional Web objects, rich media objects can benefit from proxy caching, but caching streaming media is more of challenging than caching simple Web objects, because the streaming media have features such as huge size and high bandwidth. Due to huge size of streaming media, lots of researches manage the contents with segments for efficient storage management. And to support various bandwidth requirements for the heterogeneous ubiquitous devices, a transcoding proxy is usually necessary to provide not only adapting multimedia streams to the client by transcoding, but also caching them for later use. In this paper, we propose the hybrid segmentation strategy for the transcoding proxy that is uniform segmentation in the same version and is also exponential segmentation among the multiple versions. This strategy reduces the replacement count than uniform segmentation and gets the similar performance to uniform segmentation. The performance results show that hybrid segmentation with aggregated profit function have a high delay saving ratio, high byte-hit ratio and less transcoding data.