Research On Distributed Workflow Management System Based On Grid

Workflow is The computerised facilitation or automation of a business process, in whole or part. Workflow is concerned with the automation of procedures where documents, information or tasks are passed between participants according to a defined set of rules to achieve, or contribute to, an overall business goal.Workflow Management System is A system that completely defines, manages and executes "workflows" through the execution of software whose order of execution is driven by a computer representation of the workflow logic. A Workflow Management System (WfMS) is one which provides procedural automation of a business process by management of the sequence of work activities and the invocation of appropriate human and/or IT resources associated with the various activity steps. Along with the rapid development of computer and network, the application scope of WfMS is not only limitted in special field and always in a distributed and heterogeneous environment.The topic of flexibility, cooperation and integration in WFMS is still opening. In this article, adopting with Grid middleware and Pi-Calculus technologies , we analyse and discuss the design of distributed workflow architecture and technology of implementation based on practical experiences. Then we introduce a prototype system.In the 1~st chapter, we firstly introduce the origin, development and future of workflow management and distributed compute. Through describeing the status in quo and the opening problems in this area, we make a conclusion that Grid is the best technology to achieve distributed workflow management.In the 2~nd chapter, we firstly describe the development period of Grid and introduce the main technology. Then on this basis, we propose a distributed architecture of WFMS. Finally we analyze several key components of it.In the 3~rd chapter, a novel formal modeling method was proposed. we first defined a formal foundation for structure modeling of inter-virtual-organizational business processes, which is based on Pi-Calculus technique. The proposed method works well on the collaboration between different workflow processes and appropriates for the modeling of distributed cooperative workflow systems.In the 4~th chapter, a distributed architecture of workflow engine is proposed. Based on this architecture, we introduce a decentralized scheduling system and describe its idea, policy and implement in detail.In the 5th chapter, based on the distributed workflow designe above, we demonstrate a prototype system.In the end, all of the works in this dissertation are summed up, and their futures are prospected.