Asymmetry Helps: Improved Private Information Retrieval Protocols for Distributed Storage
Abstract
We consider private information retrieval (PIR) for distributed storage systems (DSSs) with noncolluding nodes where data is stored using a non maximum distance separable (MDS) linear code. It was recently shown that if data is stored using a particular class of non-MDS linear codes, the MDS-PIR capacity, i.e., the maximum possible PIR rate for MDS-coded DSSs, can be achieved. For this class of codes, we prove that the PIR capacity is indeed equal to the MDS-PIR capacity, giving the first family of non-MDS codes for which the PIR capacity is known. For other codes, we provide asymmetric PIR protocols that achieve a strictly larger PIR rate compared to existing symmetric PIR protocols.
Keywords
Cite
@article{arxiv.1806.01342,
title = {Asymmetry Helps: Improved Private Information Retrieval Protocols for Distributed Storage},
author = {Hsuan-Yin Lin and Siddhartha Kumar and Eirik Rosnes and Alexandre Graell i Amat},
journal= {arXiv preprint arXiv:1806.01342},
year = {2018}
}
Comments
To be presented at 2018 IEEE Information Theory Workshop (ITW'18). See arXiv:1808.09018 for its extended version