An Anonymous Efficient Private Set Intersection Protocol for Wireless Sensor Networks

We present an efficient protocol which, under certain assumptions, provides a suitable level of security and anonymity in the ideal cipher model when computing the intersection of two private data-sets containing lists of elements from a large domain. The assumptions are that each node is pre-loaded with a set of pseudonyms, signed by the network’s trusted authority; that the cardinality of each data-set is globally known. Our protocol first establishes a secure, trusted connection between two partners, then uses lightweight, symmetrical key operations for encoding and privately comparing the elements of two sets. Given a cryptographically secure symmetric encryption scheme, our protocol is safe for both semi-honest and malicious adversaries. The primary target platform for this protocol are Wireless Sensor Networks (WSNs), specifically those used in Ambient Assisted Living (AAL) scenarios, which almost entirely consist of a heterogeneous mix of devices, providers and manufacturers.