Modelling communication in distributed systems

We argue that communication is a two dimensional phenomenon and message passing and variable sharing disciplines represent only its spatial and temporal dimensions. Thus any model, e.g. CSP or the pi calculus, which selects one absolute discipline and derives other disciplines on top of it delivers, in our opinion, only a fragmented and distorted view of communication. We discuss a method of modelling the two-dimensional communication called multi-handshake which integrates synchronous communication as well as asynchronous message passing and variable sharing at one abstraction level.