The timed-based automata model, introduced by Alur and Dill, provides a useful formalism for describing real-time systems. Over the last two decades, several dense-time model checking tools have been developed based on that model. The paper considers
the verification of real-time distributed commit protocols using dense-time model checking technology. More precisely, we model and verify the well-known timed two phase commit protocol in three different state-of-the-art real-time model checkers: UPPAAL, Rabbit, and RED, and compare the results.
The paper describes an abstraction for protocols that are based on multiple rounds of Chaums Dining Cryptographers protocol. It is proved that the abstraction preserves a rich class of specifications in the logic of knowledge, including specification
s describing what an agent knows about other agents knowledge. This result can be used to optimize model checking of Dining Cryptographers-based protocols, and applied within a methodology for knowledge-based program implementation and verification. Some case studies of such an application are given, for a protocol that uses the Dining Cryptographers protocol as a primitive in an anonymous broadcast system. Performance results are given for model checking knowledge-based specifications in the concrete and abstract models of this protocol, and some new conclusions about the protocol are derived.
Knowledge-based programs provide an abstract level of description of protocols in which agent actions are related to their states of knowledge. The paper describes how epistemic model checking technology may be applied to discover and verify concrete
implementations based on this abstract level of description. The details of the implementations depend on the specific context of use of the protocol. The knowledge-based approach enables the implementations to be optimized relative to these conditions of use. The approach is illustrated using extensions of the Dining Cryptographers protocol, a security protocol for anonymous broadcast.
