Collaborative and distributed engineering web services are emerging as a viable alternative to the traditional design and engineering process automation. Existing approaches have limitations in supporting long-running engineering transactions, synchronous and asynchronous conversation, and geometric abstraction for transmission and sharing. In this paper, we present a process-centric engineering web services framework to overcome these limitations by utilizing BPEL-based (Business Process Execution Language) process templates and coordination agent-based conversation support. This paper discusses the synchronization of engineering web services which can be either peer-centric or process-centric. In particular, the paper focuses on asynchronous peer-centric services to support long-transactions and conversation. The process orchestration and choreography agent works as a service dispatching and aggregation broker using process templates. Moreover, several coordination agents enable the individual activities of the BPEL-based engineering process to consume the alternative web service through the run-time process brokering. Additionally, the application of the coordination agents helps a process designer model a reusable BPEL-based engineering process. Further, the paper discusses how to support conversation on the running processes based on conversation policy.

Key Words: engineering web services, business process management, BPEL, process orchestration and choreography, web services, semantic web, conversation policy