Proactive content caching at user devices and coded delivery is studied for a non-uniform file popularity distribution. A novel centralized uncoded caching and coded delivery scheme, called cross-level coded delivery (CLCD) , is proposed, which can be applied to large file libraries under non-uniform demands. In the CLCD scheme, the same sub-packetization 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, users requesting files from different popularity groups can still be served by the same multicast message in order to reduce the delivery rate. Simulation results indicate more than 10% reduction in the average delivery rate for typical Zipf distribution parameter values.

中文翻译：

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针对非统一文件流行度的未编码缓存和跨级编码交付


针对非均匀文件流行度分布，研究了用户设备上的主动内容缓存和编码交付。提出了一种新的集中式非编码缓存和编码传送方案，称为跨级编码传送(CLCD)，该方案可应用于非统一需求下的大型文件库。在CLCD方案中，库中的所有文件都使用相同的子分组化，以防止在交付阶段进行额外的零填充，并且与文献中现有的方案不同，请求来自不同流行群体的文件的用户仍然可以由相同的多播消息提供服务，以降低传送速率。仿真结果表明，典型 Zipf 分布参数值的平均传递率降低了 10% 以上。