中文摘要：

Internet网络上媒体流的应用受限于应用时的网络状况，如时延、包丢失率等．本文研究通过在网络边缘处设置缓存代理来减小这些影响，提出一种新的缓存管理算法NRC，即接入媒体流服务时，用户以两种方式获取媒体流对象：一部分对象内容从代理缓存中获取，而另一部分对象内容则直接从流媒体源服务器处传输而来；从而加速媒体流接入服务，提高媒体流服务质量,算法同网络特性和媒体流特性相关．最后仿真实验证实同网络和流媒体特性相关的缓存管理算法NRC可以很好地减少服务延迟和提高媒体流的总体服务质量．

英文摘要：

Internet streaming applications are affected hy the high packet loss rates and the long delays. This paper aims at miti- gating such effects by leveraging the availability of client-side caching proxies. A novel cache management algorithm that turns the edge caches into the accelerators of streaming media delivery is presented. A salient feature of this caching algorithm is that it allows partial caching of streaming media objects and joints the delivery of content from caches and origin servers. The caching algorithms are both network-aware and stream-aware by taking into account the popularity of streaming media objects, their bit-rate requirements, and the available bandwidth between clients and servers. Our experiments demonstrate that net-work-aware caching algorithms can significantly reduce the service delay and improve overall stream quality.