Concrete Branching Bisimilarity for Processes with Time-outs
Gaspard Reghem, Rob van Glabbeek
TL;DR
The paper advances branching bisimilarity for reactive systems with time-outs by introducing concrete branching reactive bisimilarity that treats time-out transitions as visible actions, avoiding elision of time-outs. It provides a modal characterisation, rooted and generalised forms, and shows that rooted concrete branching time-out bisimilarity is a full congruence for the CCSP$^\theta_t$ language. A complete axiomatisation is given for strongly guarded processes, employing RDP/RSP, branching and reactive-approximation principles, plus canonical representatives to handle infinite cases. Together, these results enable rigorous verification of timed reactive systems within an untimed process-algebraic framework, with preserveability under recursion and environment-driven timing semantics.
Abstract
This paper provides an adaptation of branching bisimilarity to reactive systems with time-outs that does not enable eliding of time-out transitions. Multiple equivalent definitions are procured, along with a modal characterisation and a proof of its congruence property for a standard process algebra with recursion. The last section presents a complete axiomatisation for guarded processes without infinite sequences of unobservable actions.
