Running BPEL Processes without Central Engines

WS-BPEL, or simply BPEL (Business Process Execution Language), is becoming a de facto standard for web services composition. It is natural to anticipate that the compositions are performed dynamically by a large number of end-users. However, the current process technology based on central process engines impedes the adoption of BPEL for this purpose. We propose an approach to execution of BPEL processes without central engines. The approach is of continuation-passing style, where continuations, or the reminder of executions, are passed along with messages for process execution. Two continuations are associated with an execution: a success continuation and a failure continuation. Recovery plans for processes are automatically generated at runtime and attached to failure continuations. *