2007/01/01 by Aaron Hunter, Hunter, Aaron, James P. Delgrande +1
Computer Science · Social Sciences · #Access Control and Trust #Advanced Authentication Protocols Security #Belief change #Logic, Reasoning, and Knowledge #belief evolution #cryptographic protocol verification
paper · doi:10.4230/dagsemproc.07351.7
openalex publication_date 2007/01/01 · openalex created_date 2025/10/10 · openalex updated_date 2026/07/28
Cryptographic protocols are structured sequences of messages that are used for exchanging information in a hostile environment. Many protocols have epistemic goals: a successful run of the protocol is intended to cause a participant to hold certain beliefs. As such, epistemic logics have been employed for the verification of cryptographic protocols. Although this approach to verification is explicitly concerned with changing beliefs, formal belief change operators have not been incorporated in previous work. In this paper, we introduce a new approach to protocol verification by combining a monotonic logic with a non-monotonic belief change operator. In this context, a protocol participant is able to retract beliefs in response to new information and a protocol participant is able to postulate the most plausible event explaining new information. We illustrate that this kind of reasoning is particularly important when protocol participants have incorrect beliefs.