多层卫星网络数据缓存技术研究

Research on Caching of Multilayered Satellite Networks

针对星间链路和星地链路传播时延大、内容分发经过多跳传输后总体时延较大的问题,研究在多层卫星网络中部署网络内缓存技术,并提出基于卫星缓存容量大小和内容流行度的概率缓存策略。仿真结果显示,当每个卫星节点缓存容量大小仅占内容总量大小30%时,与IP协议、未部署缓存的NDN协议以及NDN-LCE缓存策略相比,采用提出的缓存策略,用户平均内容访问时延分别下降60%、53.4%和7.1%。

The propagation delay of inter-satellite link and satellite-terrestrial link is large,and so is the overall delay of content distribution after multi-hop transmission.To solve this problem,the in-network caching was deployed in the multilayered satellite networks and a probabilistic caching strategy based on satellite cache size and content popularity was proposed.The simulation results showed that when the cache capacity of each satellite node was only 30% of the total content size,the average content access delay of the proposed caching strategy decreased by 60%,53.4% and 7.1% respectively as compared with that of the IP Protocol, cache-undeployed NDN Protocol and NDN-LCE caching strategy.