Protecting the consistency of workflow applications in collaborative development environments

Collaborative development environments allow a group of users to view and edit a shared item from geographically dispersed sites. Consistency maintenance in the face of concurrent accesses to shared entities is one of the core issues in the design of these systems. The paper introduces a lock based solution and three different algorithms that enable controlled, concurrent access to workflows for multiple application developers. Collaborative development of workflow applications promises better outcome in shorter time. The described method ensures that collaborators cannot break the consistency criteria of workflows by adding cycles or invalid edges to the graphs. A formal analysis of the three graph locking algorithms is also provided, focusing on the number of users who are allowed to edit a single workflow simultaneously. Based on the findings, a more powerful fourth graph locking algorithm is defined.

► Groupware tool for workflow development with lock based concurrency control.
► Four algorithms to partition workflow graphs for concurrent workflow developers.
► Graph consistency without cancelling or compensating the developers’ work.
► A measurement method to evaluate the efficiency of graph partitioning algorithms.
► Analysis of three graph locking algorithms with the measurement method.