Proactive content caching at user devices and coded delivery is studied considering a non-uniform file popularity distribution. A novel centralized uncoded caching and coded delivery scheme, which can be applied to large file libraries, is proposed. The proposed cross-level coded delivery (CLCD) scheme is shown to achieve a lower average delivery rate than the state of art. In the proposed CLCD scheme, the same subpacketization is used for all the files in the library in order to prevent additional zero-padding in the delivery phase, and unlike the existing schemes in the literature, two users requesting files from different popularity groups can be served by the same multicast message in order to reduce the delivery rate. Simulation results indicate significant reduction in the average delivery rate for typical Zipf distribution parameter values.

翻译：考虑到非统一文件版面的普及性分布,正在研究用户装置和编码交付的预发内容缓存;提出了一个新的中央集式未编码的缓存和编码交付计划,可适用于大型文件库;拟议的跨级编码交付计划显示平均交付率低于最新水平;在拟议的CLCD计划中,图书馆的所有文件都使用同样的子包装,以防止在交付阶段出现更多的零铺盖;与文献中的现有计划不同,要求不同流行群体提供文件的2个用户可以通过同一个多播式信息服务,以降低交付率;模拟结果显示典型Zipf分配参数的平均交付率显著下降。