On modelling security protocols for logic-based verification

Formal verification is an imperative step in the design cycle of security protocols. One of the most critical steps in formal verification is the formalisation of the security protocol in the language of the verification technique, as any mistakes in the formalisation can invalidate the outcome of the verification. However, security protocols are constantly evolving. Hence, verification techniques need to be adjusted to facilitate appropriate formalisations of newly arising features or operations of security protocols. This paper concerns modelling security protocols for formal verification. Different ways to model lightweight operations in a logic-based verification tool are discussed. An extension of the verification tool, that facilitates direct modelling of lightweight operations in security protocols, is then described. Finally, a remote authentication scheme is formalised and verified using the extended tool.