The present invention relates to a work flow control system and, in particular, to a business process simulation system for verifying correctness of information defining a business process.
To increase efficiency of business work in offices, there have been introduced work flow control systems. According to such a work flow control system, a flow of business steps to be achieved by a plurality of workers and operators is expressed as a flow of documents expressed in an electronic form for automation of the business for a higher efficiency in the performance of business.
The work flow control system is implemented by a general client-server system. The system includes, as shown in FIG. 10, a work flow (WF) definition client 1001 for defining business processes, a plurality of business clients 1002 for conducting business, and a work flow (WF) manager or WF server 1004 for managing business processes and circulating documents as objects of work. The clients and servers are connected to each other via a local area network (LAN) 1005. Moreover, depending on cases, the system includes an operation management client 1003 for controlling operation of the system.
FIG. 11 shows a software layout of the work flow control system. The system includes a business process description tools 101 for defining and describing business processes, business process defining information 104 generated by the business process description tool 101, and a business process program 1106 for executing business processes according to the business process defining information. The business process program 1106 further includes a node process program 1102 for deciding and controlling flows of documents between business clients and a document control program 1103 for requesting business to each business client and collecting documents. The business process definition tool 101 is executed in the WF definition client 1001 and the business process defining information 104 is stored in a memory of the WF manager 1004. The business process program 1106 is executed by the WF manager 1004.
As an example of the work flow control system, there exists a form control system in which orders of a plurality of items are accepted to conduct delivery, accounting, and stock control for the respective items through mutually different paths.
In this connection, for information related to the work flow control system, reference is to be made, for example, "Automation of Cooperation of Business--Realization of Saving of Time and Management" described in pages 57 to 63 of "Nikkei Computer" published on May 2, 1994.
In the work flow control system described above, there has been known as a business process simulation tool a flow rate simulation tool which simulates the quantity of documents passed to respective workers. However, the simulation tool of the prior art is a tool to evaluate performance of the business processes. Namely, the tool is not prepared to verify validity or appropriateness of the defined business processes.
As above, the conventional flow rate simulation is employed on premise that the business processes defined by the business process definition tool are valid. During operation of the work flow control system, there may possibly occur abnormal states as follows. Case 1: Control is confined in a closed path in a loop. Case 2: Control is unable to conduct transition to a subsequent node due to occurrence of an abnormal state such as a deadlock.
Cases 1 and 2 take place in most cases only when an attribute value or a combination of attribute values in a document is represented in a certain pattern. In consequence, the abnormal states can be recognized only when the document is actually passed to business processes in many cases and hence it is difficult to detect such abnormality only through a syntactic check of the business process defining information.