Petri net

About: Petri net is a research topic. Over the lifetime, 25039 publications have been published within this topic receiving 406994 citations.

Conformance checking of service behavior

Abstract: A service-oriented system is composed of independent software units, namely services, that interact with one another exclusively through message exchanges. The proper functioning of such system depends on whether or not each individual service behaves as the other services expect it to behave. Since services may be developed and operated independently, it is unrealistic to assume that this is always the case. This article addresses the problem of checking and quantifying how much the actual behavior of a service, as recorded in message logs, conforms to the expected behavior as specified in a process model. We consider the case where the expected behavior is defined using the BPEL industry standard (Business Process Execution Language for Web Services). BPEL process definitions are translated into Petri nets and Petri net-based conformance checking techniques are applied to derive two complementary indicators of conformance: fitness and appropriateness. The approach has been implemented in a toolset for business process analysis and mining, namely ProM, and has been tested in an environment comprising multiple Oracle BPEL servers.

Process-Aware Information Systems: Lessons to Be Learned from Process Mining

Abstract: A Process-Aware Information System (PAIS) is a software system that manages and executes operational processes involving people, applications, and/or information sources on the basis of process models. Example PAISs are workflow management systems, case-handling systems, enterprise information systems, etc. This paper provides a brief introduction to these systems and discusses the role of process models in the PAIS life-cycle. Moreover, it provides a critical reflection on the state-of-the-art based on experiences with process mining . Process mining techniques attempt to extract non-trivial and useful information from event logs. One aspect of process mining is control-flow discovery, i.e., automatically constructing a process model (e.g., a Petri net) describing the causal dependencies between activities. The insights provided by process mining are very valuable for the development of the next generation PAISs because they clearly show a mismatch between the models proposed for driving these systems and reality. On the one hand, models tend to oversimplify things resulting in systems that are too restrictive. On the other hand, models fail to capture important aspects of business processes.

Discovering Architectures from Running Systems

Abstract: One of the challenging problems for software developers is guaranteeing that a system as built is consistent with its architectural design. In this paper, we describe a technique that uses runtime observations about an executing system to construct an architectural view of the system. In this technique, we develop mappings that exploit regularities in system implementation and architectural style. These mappings describe how low-level system events can be interpreted as more abstract architectural operations and are formally defined using colored Petri nets. In this paper, we describe a system, called DiscoTect, that uses these mappings and we introduce the DiscoSTEP mapping language and its formal definition. Two case studies showing the application of DiscoTect suggest that the tool is practical to apply to legacy systems and can dynamically verify conformance to a preexisting architectural specification

Supervisory control of discrete event systems based on structure theory of Petri nets

Abstract: The present work is related to the use of Petri nets structural techniques in the supervisory control of discrete event systems. A relevant property of the system behaviour under supervision is to be non-blocking, i.e. from any state reachable from initial state, it is always possible to reach a desirable (or marked) state. Recent works had shown that the synthesis of proper supervisors based on Petri net modelling of DES is an interesting approach. In this paper, we present a proper supervisor synthesis method based on a purely structural reasoning. This parametrized method is especially well-suited for a large class of discrete event systems, called G-Task, for modelling concurrent automated manufacturing systems with flexibility on routings and on synchronization patterns with shared resources. Also, it can be exploited for enforcing constraints on the reachability set of any bounded uncontrolled net.

Information Systems Engineering: A Formal Approach

Abstract: Engineers and scientists need powerful formalisms to make conceptual models of systems in order to analyze and design them. These models can be used to verify the behavior of the systems, or as an executable specification of them. In this book, Professor van Hee concentrates on discrete dynamic systems, e.g. computer hardware, and information and logistical systems. He develops an integrated formalism that can be used as a prototyping language. It has three components: Petri nets, extended with time, token values and hierarchy; a specification language that is a subset of Z; and a binary data model, extended with complex objects. Much attention is paid to methods for constructing models of systems and analyzing their behavior, i.e., putting the theory into practice. The book is aimed at graduate students and researchers in computer science, electrical engineering, and applied mathematics.