Process Algebras for Protocol Validation and Analysis

Process algebras are a set of mathematically rigous languages with well defined operational semantics that allow for proofs of systems and propositions, either in terms of drawing an isomorphism between two systems such that they can be said to be equivalent, or in terms of deriving a system from its base terms. Process algebras CCS and PEPA are presented as modelling languages for concurrent systems and protocols, and are given a formal definition. PEPA is presented with a worked example of the alternating bit protocol, and it is demonstrated how equivalence relations may be drawn to prove functional and behavioural properties of this protocol, and how mathematically sound performance analysis can be applied using tools associated with this language. The methodology presented here is a generic one, and could easily be applied to other systems and may be considered a framework for modelling, proving and evaluating performance of other network protocols, as well as any concurrent and cooperating system.