Coalition Overview
What is the Workflow Management Coalition?
The Workflow Management Coalition, founded in August
1993, is a non-profit, international organization of
workflow vendors, users and analysts. The Coalition's
mission is to promote the use of workflow through the
establishment of standards for software terminology,
interoperability and connectivity between workflow
products. Consisting of over 100 members, the Coalition
has quickly become established as the primary standards
body for this rapidly expanding software market.
Mission Statement
- Increase the value of customers investment with workflow technology
- Decrease the risk of using workflow products
- Expand the workflow market through increasing awareness for workflow
The Evolution of Workflow
Workflow software products, like other software
technologies, have evolved from diverse origins. While
some offerings have been developed as pure workflow
software technologies, many have evolved from image
management systems, document management systems,
relational or object database systems, and electronic mail
systems. Vendors who have developed pure workflow
offerings have invented terms and interfaces, while vendor
who have evolved products from other technologies have
often adapted terminology and interfaces. Each approach
offers a variety of strengths from which a user can choose,
adding a standards based approach which would allow a
user to combine these strengths in one infrastructure.
Workflow Standards Framework
The Coalition has proposed a framework for the
establishment of workflow standards. This framework
includes five categories of interoperability and
communication standards that will allow multiple
workflow products to coexist and interoperate within a
user's environment. Technical details are included in the
white paper titled The Work of the Coalition.
Workflow Management Coalition Structure
The Coalition is divided into two major committees, the
Technical Committee and the Steering Committee. Small
working groups exist within each committee for the
purpose of defining workflow terminology, interoperability
and connectivity standards, and for assisting in the
communication of this information to the workflow user
community.
The Coalition's major committees meet four times per
calendar year for three days at a time, with meetings
alternating between a North American location and a
European location. The working group meetings are held
during those three days and as necessary throughout the
year.
Coalition membership is open to all interested parties
involved in the creation, analysis or deployment of
workflow software systems. Membership is governed by a
Document of Understanding, which outlines meeting
regulations, voting rights, etc.
The Work of the Coalition
Overview
The objectives of the Coalition are to :
- Develop standard terminology to describe workflow
systems and their environment
- Enable interoperability between different workflow
systems
- Help users understand workflow through the standard
Reference Model
- Work with other related industry groups to set standards
and communicate its work
This document describes the work that the Coalition is
doing to meet the first two of these objectives. The latter
objectives are being addressed by a communications
program, active participation in industry events, and
liaison with other industry bodies.
Coalition Working Groups
The Coalition has established a number of working groups
each working on an area of specific interest. The work
centers on the development of a Reference Model for
workflow management systems which provides the
framework for the working parties. The Reference Model
identifies the common characteristics of workflow systems
and by specifying the discrete functional areas will set the
scene for the development of interface standards between
them.
Reference Model
In order to progress these objectives the following working
groups have been established:
- Reference Model - Specify a framework for workflow systems,
identifying their characteristics, functions and interfaces.
- Glossary - Development of standard terminology for workflow.
- Process Definition Tools Interface (1) - Define a standard
interface between the process definition tool and the workflow engine(s).
- Workflow Client Application Interface (2) - Define standards for
the workflow engine to maintain work items which the workflow client presents
to the user.
- Invoked Application Interface (3) - A standard interface to allow
the workflow engine to invoke a variety of applications.
- Workflow Interoperability Interface (4) - Definition of a variety
of interoperability models and the standards applicable to each
- Administration & Monitoring Tools Interface (5) - Definition of
monitoring and control functions.
The current focus is on the first two areas of activity since
they lay the foundation for the rest of the work.
Workflow Reference Model
All workflow systems contain a number of generic
components which interact in a variety of ways. To achieve
interoperability between workflow products a standardized
set of interfaces and data interchange formats is necessary.
A number of distinct interoperability scenarios can be
constructed by reference to such interfaces. For example a
standard process to be used by a number of groups of
users, perhaps in different organizations could be defined
using one tool and exported to each group who may use
different workflow systems. Also a given user may use one
workflow client application to receive tasks generated by a
variety of workflow systems.
The model identifies the major components and interfaces.
These are considered in turn in the following sections.
Process Definition Tools
A variety of tools may be used to analyze, model, and
describe a business process. The workflow model is not
concerned with the particular nature of such tools, and
currently each is in a form specialized for the particular
workflow management software for which it was designed.
One of the interfaces proposed by the Coalition enables
more flexibility in this area.
This interface is termed the process definition
import/export interface which would provide a common
interchange format for the following types of information:
- Process start and termination conditions
- Identification of activities within the process, including
associated applications and workflow relevant data.
- Identification of data types and access paths
- Definition of transition conditions and flow rules
- Information for resource allocation decisions
There are other industry groups working in related areas
such as process modeling and CASE tools. The Coalition
intends to work with such groups to advance the definition
of interchange formats.
Workflow Enactment Service
The workflow enactment service provides the run-time
environment in which one or more workflow processes are
executed. This may involve more than one actual workflow
engine. The enactment service is distinct from the application and
end-user tools which are used to process items of work.
A wide range of industry standard or application specific tools
can therefore be integrated with the workflow enactment service
to provide a complete workflow management system.
This integration takes two forms:
- The invoked application interface which enables the workflow
engine directly to activate a specific application to undertake a
particular activity. This would typically be server based and
require no user action, for example to invoke an Email
application or pass data to a mainframe system.
- The workflow client application interface through which the
workflow engine interacts with a separate workflow client
application responsible for organizing work on behalf of a
particular user.
Workflow Client Applications
The workflow client application is the software entity which
presents the end user with his or her work items, and may invoke
application tools which present to the user the task and the data
relating to it, and allow the user to take actions before passing the
case back to the workflow enactment service. The workflow client
application may be supplied as part of a workflow management
system or may be a third party product (such as an Email
product) or written specially for a given application.
There is thus the need for a flexible means of communication
between a workflow enactment service and the workflow client
application which would provide a series of functions for
connecting to the service and for obtaining and processing items
of work.
Invoked Applications
There is a requirement for workflow systems to deal with a range
of invoked applications; for example, to invoke an Email service
such as X400, a fax service, Document Management services or
existing user applications.
The Coalition sees value in the development of standards for the
invocation of such applications by building "tool agents" which will
provide the interface to invoke applications. In addition it is seen
that it may be possible to develop a set of APIs which will allow
other developers to build "workflow enabled" applications which
can be invoked directly from the workflow engine.
Workflow Interoperability
A key objective of the Coalition is to define standards that will
allow workflow systems produced by different vendors to pass
work items between one another. Workflow products are diverse
in nature ranging from those used for ad-hoc routing of tasks or
data to those aimed at highly regularized production processes,
each product having its own particular strengths. In its drive for
interoperability standards the Coalition is determined not to
force workflow product vendors to choose between providing a
strong product focused on the needs of its customers and giving
up those strengths just to provide interoperability.
Interoperability can work at a number of levels from simple task
passing through to workflow management systems with
complete interchange of process definition, workflow relevant
data and a common look and feel. The greatest level of
integration is unlikely to be available generally as it relies on a
commonality of approach by a wide variety of developers deep
in their products where it is likely that healthy innovation is rife.
The following interoperability approaches have been identified
and are being investigated:
- Level I - Coexistence: The ability for a number of workflow
systems to reside on the same hardware and software base
- Level 2 - Unique Gateways: Developed to allow specific workflow
systems to move work between themselves
- Level 2A - Common Gateway API: An enhancement of Unique Gateways
- Level 3 - Limited Common API: A subset of workflow product
functionality is reduced to an open API; for example: connect,
request task, and completion of task function calls
- Level 4 - Complete Workflow API: All aspects of workflow system
behavior are embodied via an open API
- Level 5 - Shared Definition Format: Each workflow product can use
the same process definitions at run time
- Level 6 - Protocol Compatibility: All APIs including transmission
of definitions, work items, and recovery is standard
- Level 7 - Common Look and Feel: Workflow product components
appearance and method of operation are very similar
Administration & Monitoring Tools
A common interface standard which will allow one vendor's
status monitoring application to work with one or more
vendor's workflow enactment service engines. Firstly it will
allow a complete view of the status of work flowing through
the organization regardless of which system it is in, and
secondly will allow the customer to choose the best monitoring
tool for their purposes.
Workflow Management Coalition Office
Avenue Marcel Thiry 204, 1200 Brussels, Belgium;
tel: +32 2 774 96 33. Fax: +32 2 774 96 90.
E-Mail: wfmc@eyam.be
WWW: http://www.wfmc.org or http://www.aiai.ed.ac.uk/WfMC
Last updated: Thu Aug 28 15:38:52 1997
by Austin Tate, AIAI (A.Tate@ed.ac.uk)