Simple and Fast Private Information Retrieval

Prof. Henry-Corrigan Gibbs MIT Monday, January 9, 2023 @ 4:15 pm Room BC 420 Hosted by: Prof. Bryan Ford

Abstract

Private-information-retrieval protocols allow a client to query a database server without revealing its query to the server. With private information retrieval, a client can, for example, download an article from Wikipedia without revealing which article it fetched. Existing schemes for private information retrieval require large amounts of computation – both asymptotically and concretely. Computational cost is the major barrier to the use of private information retrieval in practice.

This talk will present SimplePIR, the fastest single-server private-information-retrieval scheme known to date. SimplePIR improves the performance of state-of-the-art schemes by over 30x and can answer private queries to a 1 GB database in under 100ms using a single CPU core. The scheme is simple to describe and easy to implement, which gives us hope that it will see adoption in practice. After describing the new scheme, I will discuss how we might apply it to strengthen privacy protections in the Chrome web browser. The talk will conclude with a discussion of the scheme’s limitations, along with a few open problems in the area.

This talk is based on joint work with Alexandra Henzinger (MIT), Matthew Hong (MIT), Sarah Meiklejohn (Google), and Vinod Vaikuntanathan (MIT).

Bio

Henry Corrigan-Gibbs (he/him) is an assistant professor at MIT. Henry builds computer systems that provide strong security and privacy properties using ideas from cryptography, computer security, and computer systems. Henry completed his PhD in the Applied Cryptography Group at Stanford, where he was advised by Dan Boneh. After that, he was a postdoc in Bryan Ford’s research group at EPFL.

For their research efforts, Henry and his collaborators have received an ACM Doctoral Dissertation Honorable Mention Award, three IACR Best Young Researcher Paper Awards (at Eurocrypt in 2020, the Theory of Cryptography Conference in 2019 and at Eurocrypt in 2018), the 2016 Caspar Bowden Award for Outstanding Research in Privacy Enhancing Technologies, and the 2015 IEEE Security and Privacy Distinguished Paper Award. Henry’s work has been cited by IETF and NIST, and his Prio system for privacy-preserving telemetry data collection is used today in the Firefox web browser, Apple’s iOS, and Google’s Android operating system.