In: Lecture Notes in Computer Science, Vol. 1376: Recent Trends in Algebraic Development Techniques, pages 122-140. Springer-Verlag, 1997.
Abstract: This paper provides both an operational and an abstract concurrent semantics for zero-safe nets under the individual token philosophy. The main feature of zero-safe nets is a primitive notion of transition synchronization. Besides ordinary places, called stable places, zero-safe nets come equipped with zero places, which are empty in any stable marking. Connected transactions represent basic atomic computations of the system between stable markings. They must satisfy two main requirements: (i) to model interacting activities which cannot be decomposed into disjoint sub-activities, and (ii) not to consume stable tokens which were generated in the same transaction. Zero tokens act as triggers for the firings of the transactions which compose the transaction. The abstract counterpart of zero-safe net consists of a P/T net where each transition locates a distinguished transaction. The second part of the paper follows the `Petri nets are monoids' approach, making use of category theory to analyze and motivate the proposed framework. More precisely, the operational semantics of zero-safe nets is characterized as an adjunction, and the derivation of abstract P/T nets as a coreflection.
Keywords: individual tokens, transition synchronization, zero-safe nets.
Back to the Petri Nets Bibliography