The manual implementation of local controllers for autonomous agents in a distributed and concurrent setting is an ambitious and error-prune task. Synthesis algorithms, however, allow for the automatic generation of such controllers given a formal specification of the system’s goal. Recently, high-level Petri games were introduced to allow for a concise modeling technique of distributed systems with a safety objective. One way of solving these games is by a translation to low-level Petri games and applying an existing solving algorithm. In this paper we present a new solving technique for a subclass of high-level Petri games with a single uncontrollable player, a bounded number of controllable players, and a local safety objective. The technique exploits symmetries in the high-level Petri game. We report on encouraging experimental results of a prototype implementation generating the reduced state space. The results for four existing and one new benchmark family show a state space reduction by up to three orders of magnitude.

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Petri games are a multiplayer game model for the automatic synthesis of distributed systems. We compare two fundamentally different approaches for solving Petri games. The symbolic approach decides the existence of a winning strategy via a reduction to a two-player game over a finite graph, which in turn is solved by a fixed point iteration based on binary decision diagrams (BDDs). The bounded synthesis approach encodes the existence of a winning strategy, up to a given bound on the size of the strategy, as a quantified Boolean formula (QBF). In this paper, we report on initial experience with a prototype implementation of the bounded synthesis approach. We compare bounded synthesis to the existing implementation of the symbolic approach in the synthesis tool ADAM. We present experimental results on a collection of benchmarks, including one new benchmark family, modeling manufacturing and workflow scenarios with multiple concurrent processes.

The correctness of networks is often described in terms of the individual data flow of components instead of their global behavior. In software-defined networks, it is far more convenient to specify the correct behavior of packets than the global behavior of the entire network. Petri nets with transits extend Petri nets and Flow-LTL extends LTL such that the data flows of tokens can be tracked. We present the tool AdamMC as the first model checker for Petri nets with transits against Flow-LTL. We describe how AdamMC can automatically encode concurrent updates of software-defined networks as Petri nets with transits and how common network specifications can be expressed in Flow-LTL. Underlying AdamMC is a reduction to a circuit model checking problem. We introduce a new reduction method that results in tremendous performance improvements compared to a previous prototype. Thereby, AdamMC can handle software-defined networks with up to 82 switches.