论文标题
多访问缓存的多用户私人信息检索
Multi-Access Cache-Aided Multi-User Private Information Retrieval
论文作者
论文摘要
我们考虑多访问高速缓存的多用户私人信息检索（Mupir）的问题。在此问题中，几个文件都在多个服务器上复制。有$ K $用户和$ C $ CACHENODES。每个用户都可以访问$ L $ CACHE节点，并且几个用户可以访问每个缓存节点。每个用户都想从服务器中检索一个文件，但是用户不希望服务器知道其需求。在用户决定各自的需求之前，服务器将从文件内容中填充缓存节点。然后，用户将从服务器请求所需的文件。服务器将执行编码的传输，所有用户都应从这些传输中获取所需的文件以及放置在访问的缓存中的内容。要求任何单个服务器都不应获得有关用户需求的任何信息。这个问题是专用的高速缓存Mupir问题的扩展，该问题本身概括了所研究的单用户PIR设置。在本文中，我们提出了一种Mupir方案，该方案利用了编码的缓存问题的多访问设置。当$ k = \ binom {c} {l} $用户时，提出的方案是最佳订单。我们还表征了循环环境多访问设置的特殊情况的计划速率，其中$ c = k $，每个用户访问$ l $ cose连续的cache nodes以环形环绕方式。
We consider the problem of multi-access cache-aided multi-user Private Information Retrieval (MuPIR). In this problem, several files are replicated across multiple servers. There are $K$ users and $C$ cache nodes. Each user can access $L$ cache nodes, and every cache node can be accessed by several users. Each user wants to retrieve one file from the servers, but the users do not want the servers to know their demands. Before the users decide their respective demands, servers will fill the cache nodes from the content of the files. Users will then request their desired files from the servers. Servers will perform coded transmissions, and all the users should get their desired files from these transmissions and the content placed in the caches they are accessing. It is required that any individual server should not get any information about the demands of the users. This problem is an extension of the dedicated cache-aided MuPIR problem, which itself generalizes the widely studied single user PIR setup. In this paper, we propose a MuPIR scheme which utilizes a multi-access setup of the coded caching problem. The presented scheme is order optimal when $K=\binom{C}{L}$ users. We also characterize the rate of the scheme for the special case of cyclic wraparound multi-access setup, where $C=K$ and each user access $L$ consecutive cache nodes in cyclic wraparound fashion.
