Petri Nets.

In 1962, C.A. Petri introduced in his Ph.D. thesis [351] a formalism for describing distributed processes by extending state machines with a notion of concurrency. Due to the simple and intuitive, but at the same time formal and expressive, nature of his formalism, Petri Nets became an established tool for modelling and analyzing distributed processes in business as well as the IT sector. This chapter gives a brief introduction to the theory of Petri Nets and shows how Petri Nets can be applied for effective workflow management with regard to the choreography, orchestration, and enactment of e-Science applications. While choreography deals with the abstract modelling of applications, orchestration deals with the mapping onto concrete software components and the infrastructure. During the enactment of e-Science applications, runtime issues, such as synchronization, persistence, transaction safety, and fault management, are examined within the workflow formalism. [ABSTRACT FROM AUTHOR]