Local Private Information Retrieval: A New Privacy Perspective for Graph-Based Replicated Systems

Fuente: arXiv
Saved in:
Bibliographic Details
Main Authors: Meel, Shreya, Nomeir, Mohamed, Ulukus, Sennur
Format: Preprint
Published: 2026
Subjects:
Online Access:
Tags: Add Tag
No Tags, Be the first to tag this record!
_version_ 1866909033580986368
author Meel, Shreya
Nomeir, Mohamed
Ulukus, Sennur
author_facet Meel, Shreya
Nomeir, Mohamed
Ulukus, Sennur
contents We rethink the definition of privacy in multi-server, graph-replicated private information retrieval (PIR) systems, and introduce a novel setting where the user's privacy is governed by the servers' storage structure. In particular, while retrieving a message from a server, the user is concerned with hiding their desired message index from the server, only if the server stores the corresponding message. We coin this privacy requirement as local user privacy and the resulting PIR problem as local PIR on the graph. Our goal is to measure the gain in communication efficiency of local PIR, compared to that of canonical PIR, by establishing its capacity, i.e., the maximum number of message symbols retrieved, per downloaded symbol. To this end, we observe a remarkable gain in the local PIR capacity of graphs, that are disjoint union of distinct graphs, which is multiplicative, compared to the PIR capacity, when the individual graphs are identical. For connected graphs, we propose schemes to establish capacity lower bounds for edge-transitive and bipartite graphs, which are greater than the best-known PIR capacity bounds. Finally, we derive the exact local PIR capacity for the cyclic graph, and the path graph with an odd number of vertices.
format Preprint
id arxiv_https___arxiv_org_abs_2605_10872
institution arXiv
publishDate 2026
record_format arxiv
spellingShingle Local Private Information Retrieval: A New Privacy Perspective for Graph-Based Replicated Systems
Meel, Shreya
Nomeir, Mohamed
Ulukus, Sennur
Information Theory
Cryptography and Security
Networking and Internet Architecture
Signal Processing
We rethink the definition of privacy in multi-server, graph-replicated private information retrieval (PIR) systems, and introduce a novel setting where the user's privacy is governed by the servers' storage structure. In particular, while retrieving a message from a server, the user is concerned with hiding their desired message index from the server, only if the server stores the corresponding message. We coin this privacy requirement as local user privacy and the resulting PIR problem as local PIR on the graph. Our goal is to measure the gain in communication efficiency of local PIR, compared to that of canonical PIR, by establishing its capacity, i.e., the maximum number of message symbols retrieved, per downloaded symbol. To this end, we observe a remarkable gain in the local PIR capacity of graphs, that are disjoint union of distinct graphs, which is multiplicative, compared to the PIR capacity, when the individual graphs are identical. For connected graphs, we propose schemes to establish capacity lower bounds for edge-transitive and bipartite graphs, which are greater than the best-known PIR capacity bounds. Finally, we derive the exact local PIR capacity for the cyclic graph, and the path graph with an odd number of vertices.
title Local Private Information Retrieval: A New Privacy Perspective for Graph-Based Replicated Systems
topic Information Theory
Cryptography and Security
Networking and Internet Architecture
Signal Processing
url https://arxiv.org/abs/2605.10872