Research And Application On Workflow Data Model

Data are essential parts of enterprise business process. Along with prevalence of Internet, traditional centralized applications are transformed into distributed ones, so more data including key and confidential data transmit on-line heavy. Meanwhile, due to applications of workflow in special departments, such as the department of military or bank, the confidentiality of data is requested more and more highly. Therefore, the research on security and access right of workflow data is more and more important. On the other hand, because the external environment of workflow management system of practical applications is complicated and changeable, diversified exceptions will inevitably occur during workflow instances executing, which cause mistakes of data during workflow executing. Therefore, it is urgent to adopt some measures to protect the consistency of data.The paper firstly comprehensively introduces research situation on workflow data, in which status and function of data in workflow system, classification of workflow data, research of data consistency and authority etc. are contained. Then, based on application of practical system, a modeling method of workflows case relevant data (WRID) is proposed in which a workflow instance is represented as system net of object Petri net, while access mechanism of WRID is represented as object net of object Petri net, to guarantee the security of WRID. Furthermore, an improvement of a version management mechanism of WRID is introduced. Four models of basic routing WRID: the sequential routing model, the choice routing model, iteration routing model and concurrent routing model as well as data consistency of them are discussed. And a collaborative communication mechanism of concurrent tasks is established to solve inconsistency of data during the execution of workflow. Finally, the model of WRID is applied into the laboratory project: document flow sub-system of Office Automation System. The result has shown that the model effectively guarantee access right and integrality control of WRID without adding any modeling complexity.