Process algebraic frameworks for the specification and analysis of cryptographic protocols

Two process algebraic approaches for the analysis of cryptographic protocols, namely the spi calculus by Abadi and Gordon and CryptoSPA by Focardi, Gorrieri and Martinelli, are surveyed and compared. We show that the two process algebras have comparable expressive power, by providing an encoding of the former into the latter. We also discuss the relationships among some security properties, i.e., authenticity and secrecy, that have different definitions in the two approaches.