Proxy caching and video segmentation based on request frequencies and access costs

Partial caching of large media objects such as video files has been proposed in recent proxy caching schemes, as the caching of entire videos can exhaust proxy storage resources within few requests. In this work, the idea of segmenting videos into a number of chunks and replacement decisions can be taken at the chunk level rather than based on the entire objects adopted. In particular, a video segmentation scheme called variable chunk size is presented. This scheme uses the request frequencies to dynamically adjust the size of the chunk and it is shown to be capable of combining a high BHR (byte hit ratio) with small response time to demand changes. Video segmentation is also considered as a mechanism to provide for caching differentiation based on access costs. By employing access cost dependent chunk sizes, an overall access cost reduction is demonstrated.