Honesty by Typing

Abstract

Abstract. We propose a type system for a calculus of contracting processes. Processes may stipulate contracts, and then either behave honestly, by keeping the promises made, or not. Type safety guarantees that a typeable process is honest -that is, the process abides by the contract it has stipulated in all possible contexts, even those containing dishonest adversaries.

Choreographies in the wild

“…Here, instead, we require that the participant is ready (Definition 5.5) in all possible contexts, similarly to [18]. The two notions are equivalent in the contract model based on binary session types considered in [18]. In the present paper, a similar correspondence is highlighted by Theorem 6.1, which states that an honest participant A who is culpable at some session s can always fire some do s after a sequence of its own moves.…”

“…Just like contract ready sets, the interactions are represented by participant/sort pairs. Definition 5.3 is adapted from [18] to suit our multiparty contract model.…”

“…As in [18], the definition of honesty subsumes a fair scheduler, eventually allowing participants to fire persistently (weakly) enabled do actions.…”

“…Here, instead, we require that the participant is ready (Definition 5.5) in all possible contexts, similarly to [18]. The two notions are equivalent in the contract model based on binary session types considered in [18].…”

“…Two different approaches have been proposed in [18,24], where CO 2 is instantiated with binary session types. In [18], a type system for CO 2 processes is presented, associating behavioural types to all session variables used in a processe; honesty is then verified by model checking these behavioural types.…”