Private interrogation of devices via identification codes

Abstract

Consider a device that wants to communicate with another device (for instance a contactless one). We focus on how to withstand privacy threats in such a situation, and we here describe how to query the device and then identify it, with a new identification protocol solution. The interrogation step uses the concept of identification codes introduced by Ahlswede and Dueck. We show that this probabilistic coding scheme indeed protects the device against an eavesdropper who wants to track it. In particular, when using a special class of identification codes due to Moulin and Koetter that are based on Reed-Solomon codes, we directly depend on the hardness of a cryptographic assumption known as the Polynomial Reconstruction problem. We analyse the security and privacy properties of our proposal in the privacy model for contactless devices introduced by Vaudenay at ASIACRYPT 2007. We finally explain how to apply our scheme with very low-cost devices. © 2009 Springer-Verlag.