On the Optimal Communication Complexity of Error-Correcting Multi-Server PIR
On the Optimal Communication Complexity of Error-Correcting Multi-Server PIR
复制标题
纠错多服务器PIR的最优通信复杂度
DOI:
10.1007/978-3-031-22368-6_3
复制
发表时间:
2022
期刊:
影响因子:
--
通讯作者:
Koji Nuida
中科院分区:
文献类型:
--
作者:
Reo Eriguchi;Kaoru Kurosawa;Koji Nuida
An-server Private Information Retrieval (PIR) scheme enables a client to retrieve a data item from a database replicated amongservers while hiding the identity of the item. It is calledb-error-correcting if a client can correctly compute the data item even in the presence ofbmalicious servers. It is known thatb-error correction is possible if and only if. In this paper, we first prove that if error correction is perfect, i.e., the client always corrects errors, the minimum communication cost ofb-error-correcting-server PIR is asymptotically equal to that of regular-server PIR as a function of the database sizen. Secondly, we formalize a relaxed notion of statisticalb-error-correcting PIR, which allows non-zero failure probability. We show that as a function ofn, the minimum communication cost of statisticalb-error-correcting-server PIR is asymptotically equal to that of regular-server one, which is at most that of-server one. Our main technical contribution is a generic construction of statisticalb-error-correcting-server PIR for anyfrom regular-server PIR. We can therefore reduce the problem of determining the optimal communication complexity of error-correcting PIR to determining that of regular PIR. In particular, our construction instantiated with the state-of-the-art PIR schemes and the previous lower bound for single-server PIR result in a separation in terms of communication cost between perfect and statistical error correction for any.