Asynchronous π-calculus & DEL

In the full π-calculus by Milner, Parrow and Walker [7] all communication is done by synchronous interaction between processes. In terms of knowledge, this situation has an important consequence, that is, common knowledge is achieved on every interaction. However, many communication scenarios that arise in Computer Science, require to consider asynchronous interaction. A common example can be found on the Consensus Problem, better known as the “Byzantine Generals Problem”[6]. Asynchronous version of π-calculus is a subcalculus of Milner’s one. It was originally proposed by Honda and Tokoro [5] and later also by Boudol [4]. Here we will use the later with the semantics that appear in [3]. Also, asynchronous bisimulation was proposed in [1].