Function Secret Sharing for PSI-CA:With Applications to Private Contact Tracing

24 Dec 2020  ·  Samuel Dittmer, Yuval Ishai, Steve Lu, Rafail Ostrovsky, Mohamed Elsabagh, Nikolaos Kiourtis, Brian Schulte, Angelos Stavrou ·

In this work we describe a token-based solution to Contact Tracing via Distributed Point Functions (DPF) and, more generally, Function Secret Sharing (FSS). The key idea behind the solution is that FSS natively supports secure keyword search on raw sets of keywords without a need for processing the keyword sets via a data structure for set membership. Furthermore, the FSS functionality enables adding up numerical payloads associated with multiple matches without additional interaction. These features make FSS an attractive tool for lightweight privacy-preserving searching on a database of tokens belonging to infected individuals.

PDF Abstract

Categories


Cryptography and Security

Datasets


  Add Datasets introduced or used in this paper