Move vs Copy: Towards a Formal Comparison of Ambients and Higher-Order Process Calculi

C. Di Giusto and J.A. Pèrez
Appeared as Technical Report of ICTCS 2009, pp: 107-112
We describe ongoing work on a formal comparison between Ambient-like and higher-order process calculi. Both formalisms are similar in that they communicate complex objects. Also, in both cases the associated behavioral theory can be hard to define, and employs similar techniques. However, some other characteristics suggest deep differences. Communication in Ambients resembles a “move” operation whereas in higher-order settings it is better assimilated to a “copy” operation. Most notably, there is a subtle discrepancy when it comes to scoping: most (higher-order) process calculi adopt static scoping only, whereas Ambient-like formalisms exhibit features of both static scoping and dynamic binding. As a first step towards a comparison, here we present an encoding of Ambients into a higher-order calculus with dynamic scoping.