Coded caching scheme provides us an effective framework to realize additional coded multicasting gain by exploiting coding into multiple transmitted signals. The goal of coded caching design is to jointly optimize the placement and delivery scheme so as to minimize the amount of transmitted coded signals. However, few research efforts consider multiple-round coded caching design problem, in which fixed and mobile users may coexist in one network, namely different number of active users present in successive rounds. Obviously, such dynamic network configurations may lead to undesired frequent placement caching content updating at user sides, if we assume coded caching scheme for all users in each round separately. Thus how to tailor the coded caching design, such that the frequent caching content updating in the placement phase can be avoided, and simultaneously retaining full caching gain in delivery phase in multiple rounds will become highly desirable. In this paper, by carefully examining the bipartite graph representation of the coded caching scheme, a dynamic centralized coded caching design is proposed on the basis of the concatenating-based placement and the saturating matching based delivery scheme. Our analysis unveils that, the proposed dynamic coded caching scheme can realize the flexible coded multicast, and is order optimal.

中文翻译：

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论动态集中编码缓存设计

编码缓存方案为我们提供了一个有效的框架，通过利用编码到多个传输信号中来实现额外的编码多播增益。编码缓存设计的目标是联合优化放置和传递方案，以最小化传输的编码信号量。然而，很少有研究工作考虑多轮编码缓存设计问题，其中固定和移动用户可能共存于一个网络中，即连续轮次出现不同数量的活跃​​用户。显然，如果我们分别假设每一轮所有用户的编码缓存方案，这种动态网络配置可能会导致用户侧不希望的频繁放置缓存内容更新。从而如何裁剪编码缓存设计，避免在放置阶段频繁更新缓存内容，并且在多轮交付阶段同时保持完全缓存增益将变得非常可取。在本文中，通过仔细研究编码缓存方案的二部图表示，在基于级联的放置和基于饱和匹配的传递方案的基础上，提出了一种动态集中式编码缓存设计。我们的分析表明，所提出的动态编码缓存方案可以实现灵活的编码组播，并且是顺序最优的。在基于级联的放置和基于饱和匹配的交付方案的基础上，提出了一种动态集中编码缓存设计。我们的分析表明，所提出的动态编码缓存方案可以实现灵活的编码组播，并且是顺序最优的。在基于级联的放置和基于饱和匹配的交付方案的基础上，提出了一种动态集中编码缓存设计。我们的分析表明，所提出的动态编码缓存方案可以实现灵活的编码组播，并且是顺序最优的。