Minimizing information leakage of tree-based RFID authentication protocols using alternate tree-walking

Abstract

The privacy of efficient tree-based RFID authentication protocols is heavily dependent on the branching factor at the top layer. Indefinitely increasing the branching factor, however, is not a practical option. This paper proposes an alternate tree-walking scheme as well as two protocols to circumvent this problem. The privacy of the resulting protocols is shown to be comparable to that of linear-time protocols, where there is no leakage of information, whilst reducing the computational load of the database by one-third of what is required of tree-based protocols during authentication. We also identify and address a limitation in quantifying privacy in RFID protocols. © 2012 Springer-Verlag.