Towards Plugging Privacy Leaks in Domain Name System

TL;DR

This paper introduces PPDNS, a privacy-preserving DNS system that uses distributed hash tables and cryptographic techniques to enhance user privacy during domain name resolution, addressing fundamental privacy leaks in current DNS protocols.

Contribution

The paper proposes PPDNS, combining DHTs and cPIR to improve DNS query privacy and reduce communication overhead, a novel approach in DNS privacy preservation.

Findings

PPDNS significantly enhances privacy during DNS queries.

PPDNS reduces communication overhead for bandwidth-sensitive clients.

Analysis confirms PPDNS's viability for higher privacy in DNS resolution.

Abstract

Privacy leaks are an unfortunate and an integral part of the current Internet domain name resolution. Each DNS query generated by a user reveals -- to one or more DNS servers -- the origin and target of that query. Over time, a user's browsing behavior might be exposed to entities with little or no trust. Current DNS privacy leaks stem from fundamental DNS features and are not easily fixable by simple patches. Moreover, privacy issues have been overlooked by DNS security efforts (i.e. DNSSEC) and are thus likely to propagate into future versions of DNS. In order to mitigate privacy issues in current DNS, this paper proposes a Privacy-Preserving Domain Name System (PPDNS), which maintains privacy during domain name resolution. PPDNS is based on distributed hash tables (DHTs), an alternative naming infrastructure, and computational private information retrieval (cPIR), an advanced cryptographic construct. PPDNS takes advantage of the DHT's index structure to improve name resolution query privacy, while leveraging cPIR to reduce communication overhead for bandwidth-sensitive clients. Our analysis shows that PPDNS is a viable approach for obtaining a higher degree of privacy for name resolution queries. PPDNS also serves as a demonstration of blending advanced systems techniques with their cryptographic counterparts.