Formal description and validation of an interaction policy in an object-oriented framework

Formal methods are increasingly used to validate the design of software and hardware components of safety critical systems. We describe here a case study where a formal verification method was applied in practice. As a case study we have considered a safe interaction policy between communicating objects, the Multiple Levels of Integrity policy. This policy can be seen as a communication protocol that guarantees the integrity of sensible data. Formal specification is given using a process algebra, and validation is done following a model checking approach.