Providing Transactional Properties for Migrating Workflows

The paper deals with two limitations of current workflow management systems: the lack of workflow flexibility necessary in today's changing business environment, and the lack of transactional guarantees for workflow applications. To handle the dynamic character of business processes, we have proposed the Migrating Workflow Model. A migrating workflow transfers its code (specification) and its execution state to a site, negotiates a service to be executed on its behalf, receives the results, and moves on. Thus, the actual workflow instance is defined during run-time, as an effect of interactions between the static workflow specification, the local rules, and the decisions made by the user. The transactional properties are addressed by merging of the Migrating Workflow Model with a Transactional Workflow Model, in which the workflow are endowed with properties such as failure atomicity and execution atomicity. The result is a migrating workflow model that guarantees the correct execution of workflow applications in the presence of failures and accesses to shared data.