Towards a WPSL: A Critical Analysis of the 20 Classical Worko w Control-o w Patterns

In 2000, after a comprehensive survey of tools and techniques for worko w management, 20 control-o w patterns were identied (5) and made these available through www.worko wpatterns.com. Since then, many commercial and academic worko w management systems have been evaluated using these patterns. Moreover, standards such as BPEL and XPDL have been evaluated and these evaluations have triggered improve- ments in them. Although the 20 worko w patterns have proven to be useful, the selection of these patterns was done in an ad-hoc manner and the description of the patterns in natural language has been rather am- biguous. Therefore, we propose a more analytical approach using a new Worko w Pattern Specication Language (WPSL). WPSL is independent of any implementation language utilized by contemporary worko w man- agement systems. In this paper, we analyze the 20 original worko w pat- terns using WPSL, discuss the dieren t variants of the patterns, and use WPSL to capture the detailed semantics of existing worko w management systems.