Investigating performance insights of segment-based proxy caching of streaming media strategies
Songqing Chen, Bo Shen, Susie J. Wee, Xiaodong Zhang · Proceedings of SPIE, the International Society for Optical Engineering/Proceedings of SPIE · 2003
In general, existing segment-based caching strategies target one of the following two performance objectives: (1) reducing client startup delay by giving a high priority to cache the beginning segments of media objects, or (2) reducing server traffic by caching popular segments of media objects. Our previous study has shown that the approach targeting the second objective has several advantages over the first one. However, we have also observed that the effort of improving server traffic reduction can increase client startup delay, which may potentially offset the overall performance gain. Little work so far has considered these two objectives in concert. In this paper, we first build an analytical model for these two types of typical segment-based caching approaches. The analysis on the model reveals the nature of the trade-off between two performance objectives and the bounds of each are given under certain circumstances. To provide a feasible way to evaluate different strategies, we propose a new comprehensive performance metric based on the analysis. To understand this performance trade-off, we restructure the adaptive-lazy segmentation strategy with a heuristic replacement policy to improve overall performance. The evaluation results confirm our analysis and show the effectiveness of our proposed new performance metric.