An improved timed automata model for computing exact worst-case delays of AFDX periodic flows

In Avionics Switched Ethernet network (AFDX), guarantees on worst-case end-to-end (E2E) communication delays are obtained thanks to safe upper bounds computed by Network Calculus and Trajectory Approaches. Up to now, the computation of an exact worst-case delay is intractable, except for very small configurations. This paper proposes a modified timed automata approach which increases the size of the configuration for which an exact worst-case can be obtained. This is achieved thanks to a drastic reduction of the search space.