Private Information Retrieval over Random Linear Networks

TL;DR

This paper introduces a new private information retrieval scheme over random linear networks that minimizes communication costs and withstands server collusion, applicable to both error-free and error-prone network conditions.

Contribution

The paper proposes a novel PIR scheme tailored for random linear networks that reduces communication overhead and tolerates server collusion, extending privacy guarantees in distributed storage systems.

Findings

Achieves low communication cost for PIR in random linear networks.

Supports colluding servers in the privacy-preserving scheme.

Effective in both error-free and erroneous network scenarios.

Abstract

In this paper, the problem of providing privacy to users requesting data over a network from a distributed storage system (DSS) is considered. The DSS, which is considered as the multi-terminal destination of the network from the user's perspective, is encoded by a maximum rank distance (MRD) code to store the data on these multiple servers. A private information retrieval (PIR) scheme ensures that a user can request a file without revealing any information on which file is being requested to any of the servers. In this paper, a novel PIR scheme is proposed, allowing the user to recover a file from a storage system with low communication cost, while allowing some servers in the system to collude in the quest of revealing the identity of the requested file. The network is modeled as a random linear network, i.e., all nodes of the network forward random (unknown) linear combinations of incoming packets. Both error-free and erroneous random linear networks are considered.