Workflow Reference Model

Workflow Reference Model(Workflow Reference Model) is the architecture model of the workflow management system proposed by the workflow management Alliance in 1995.

The workflow reference model identifies the basic components that constitute the workflow management system and the interfaces that these basic components interact. These basic components include: workflow execution service, workflow engine, process definition tool, client application, calling application, and management and monitoring tool. interfaces used for interaction between basic components include: interface 1, interface 2, Interface 3, interface 4, and interface 5. This model greatly affected the discussion of workflow technology later.

Reference Components in the Model

The basic components and interfaces of the workflow reference model identity are as follows:

• Workflow execution serviceIs the core component of the workflow management system. Its functions include creating and managing process definitions, creating, managing, and executing process instances, applications may interact with the workflow execution service through programming interfaces. A workflow execution service may contain multiple distributed workflow engines.
• Workflow EngineIs a software component that provides a runtime environment for the process instance and explains the execution process instance.
• Process definition toolIt is a tool used to manage process definitions. It may display and operate complex process definitions graphically. The process definition tool interacts with the workflow execution service.
• Client applicationIt is an application that interacts with the workflow execution service through a request, that is, the client application calls the workflow execution service, and the client application interacts with the workflow execution service.
• Call an applicationIt is an application called by the workflow execution service. The called Application interacts with the workflow execution service. To collaborate to complete the execution of a process instance, different workflow execution services interact with each other.
• Management and monitoring toolsIt mainly refers to the maintenance and management of organization and role data and monitoring of process execution. management and monitoring tools interact with workflow execution services.
• Reference interfaces in the Model
  • Interface 1 (workflow definition exchange) is used to exchange workflow definitions between modeling and definition tools and execution services. Mainly data exchange formats and APIs. Data exchange is implemented through xpdl, and API is implemented through WAPI.
  • Interface 2 (workflow client application interface) is used for the workflow client application to access the workflow engine and work list, which is completed through WAPI.
  • Interface 3 (called application interface) is used to call different application systems.
  • Interface 4 (workflow system interoperability Interface) is used for interoperability between different workflow systems.
  • Interface 5 (system management and monitoring) is used for system management applications to access the workflow execution service.