This chapter introduces the basic concepts of information control net (ICN) and its workflow models. In principle, a workflow model is the theoretical basis of a workflow modeling methodology as well as a workflow enactment architecture. Particularly, the workflow model is directly related with how its major components are embodied for implementing the underlying workflow enactment system, too. Accordingly, the authors describe the graphical and formal representations of ICN-based workflow model and its advanced models-role-based model and actor-based model-that can be automatically transformed from the ICN-based workflow model in order to improve their verifiability, maintainability and usability. Conclusively stating, we strongly believe that the ICN-based workflow model and its advanced models be very useful not only for maximizing the quality of workflows but also for strengthening theoretical backgrounds of the recent research issues, such as workflow verification/validation, workflow reengineering, workflow intelligence, workflow mining/rediscovery, and advanced workflow architectures, and so on.
As shown in Figure 1, which is slightly modified from (Ellis & Nutt, 1993), a workflow management system is based upon two conceptual supports as well as two sets of functional supports; the former is workflow model and workflow architecture, and the latter is a set of modeling-related tools and another set of enacting-related tools. The modeling-related tools used to contain those graphical tools for a modeler to define, analyze, and maintain all the information necessary to describe a workflow procedure. In other words, in order to efficiently modeling a workflow procedure it is necessary to be supported by several tools, such as graphical editor and browser, simulator, animator, debugger and administrating tool. The workflow editor and browser take in charge of graphical editing supports to the specifications of workflow procedures, and the workflow language and its verification tools are to check the integrity of the specified workflow models. Particularly, the simulator and animator are used to checking up the pragmatical properties of the specified workflow models. Last of all, a defined and verified workflow model through those tools’ supports is translated into one of the workflow languages like WPDL3 or XPDL4.
The constituents of a workflow management system