Multipoint session types for a distributed calculus

Session types are a means of statically encoding patterns of interaction between two communicating parties. This paper explores a distributed calculus with session types in which a number of fixed sites interact. The reduction schemes describing the operational semantics satisfy the locality principle: at most one site is involved. Both session engagement and data communication are local and asynchronous. Furthermore, our setting is a natural one in which the novel notion of multipoint session types, sessions in which more than two parties may be involved, can be introduced.