An extension of coded caching referred to as multi-access coded caching where each user can access multiple caches and each cache can serve multiple users is considered in this paper. Most of the literature in multi-access coded caching focuses on cyclic wrap-around cache access where each user is allowed to access an exclusive set of consecutive caches only. In this paper, a more general framework of multi-access caching problem is considered in which each user is allowed to randomly connect to a specific number of caches and multiple users can access the same set of caches. For the proposed system model considering decentralized prefetching, a new delivery scheme is proposed and an expression for per user delivery rate is obtained. A lower bound on the delivery rate is derived using techniques from index coding. The proposed scheme is shown to be optimal among all the linear schemes under certain conditions. An improved delivery rate and a lower bound for the decentralized multi-access coded caching scheme with cyclic wrap-around cache access can be obtained as a special case. By giving specific values to certain parameters, the results of decentralized shared caching scheme and of conventional decentralized caching scheme can be recovered.

翻译：本文研究了称为多接入编码缓存的缓存扩展方案，其中每个用户可接入多个缓存，每个缓存可服务多个用户。现有文献多关注循环环绕式缓存接入模式，即每个用户仅允许访问一组专属的连续缓存。本文考虑更通用的多接入缓存问题框架，允许每个用户随机连接特定数量的缓存，且多个用户可访问同一组缓存。针对所提出的采用去中心化预取的系统模型，本文设计了一种新的交付方案，并得到了每用户交付速率的表达式。利用索引编码技术推导出了交付速率的下界。在特定条件下，所提方案在所有线性方案中达到最优。作为特例，可得到循环环绕式缓存接入的去中心化多接入编码缓存方案的改进交付速率及下界。通过为特定参数赋予具体数值，可恢复去中心化共享缓存方案和传统去中心化缓存方案的结果。