Title: Functions and Architecture of Workflow System
1Functions and Architecture of Workflow System
2Role of Workflow Management Systems
- Information systems must meet a number of
requirements - IS must set up in such a way that the structure
of the business processes is clearly reflected. - There should be an integrated approach, which
also encompasses non-computerized tasks. - IS must be set up in such a way that the
structure of the business processes can easily be
modified. - The performance of a business process can be
tracked properly, so that any problems can be
discovered at an early stage. - Good workload management is crucial to achieving
effective and efficient business processes.
3Role of Workflow Management Systems
- How information systems are traditionally
structured? - Process management has not been separated from
the application software in information systems. - The process management has been hidden inside the
information system. - Little attention been paid to process structure
within the framework of traditional systems, it
has often been difficult to actually recognize
the business process. - The process contained in the system has sometimes
been incorrect or incomplete.
4Role of Workflow Management Systems
5Role of Workflow Management Systems
- Advantages--
- This makes it possible to reuse the same
functionality in more than one task. - This makes it possible to rearrange the business
process at a later stage. - In this way, it is even possible to integrate new
applications with legacy systems. - The process execution is more manageable, with
progress and bottlenecks being more easy to check.
6A REFERENCE MODEL
- WFMC,1996
- Workflow Enactment Service
- Process Definition Tools
- Workflow Client Applications
- Invoked Applications
- Administration and Monitoring Tools
7A REFERENCE MODEL
8Workflow Enactment Service
- The heart of a workflow system.
- The Enactment Service may consist of several
workflow engines. - Workflow engine
- creating new cases and removing completed ones.
- routing cases, using the interpretation of the
appropriate process definition. - submitting work items to the correct resources
(employees), based upon resource - classification.
- managing and handling triggers.
- starting up application software during the
performance of an activity. - recording historical data.
- providing a summary of the workflow.
- monitoring the consistency of the workflow.
9Process Definition Tools
- The process definition tool
- The resource classification tool
- The analysis tool
10Process Definition Tools
- Ability to establish process definitions (name,
description, date, version, components, and so
on). - Ability to model sequential, parallel, selective
and iterative routing by means of such graphic
components as the AND-split, AND-join, OR-split
and OR-join. - Version-management support (after all, there may
be several versions of the same process) . - Definition of case attributes used in the process
. - Task specification.
- Checking of the (syntactical) correctness of a
process definition and the tracing of any
omissions or inconsistencies.
11Process Definition Tools
- The following is established for each task
- name and description of the task
- task information - any instructions and
supporting information for the employee
performing the task - the requirements with respect to the resource
carrying out the task (for example, a
specification of its role and organizational
unit, or information about the separation of
functions) - the task's routing characteristics (AND-split,
AND-join, OR-split, OR-join) - the specification of any triggers required
- instructions for the workflow engine (for
example priorities, case management and resource
management)
12Process Definition Tools
- The resource classification tool
- A list of the resource classes, often subdivided
into roles (based upon qualifications, functions
and skills) and organizational units (based upon
arrangement into teams, branches and/or
departments). - Any specific characteristics of a resource class.
- Relationship between the various resource classes
(for example, a hierarchy of roles or
organizational units).
13Process Definition Tools
- The analysis tool
- Before a workflow which has been defined can go
'into production', it is first useful to analyze
it.
14Workflow Client Applications
- The standard worklist handler
- Work items may be preformed by an employee
- Provide relevant properties of a work item
- Sort or select work item by properties
- Report the completion of an activity
- The integrated worklist handler
- This specific worklist (customized worklist
handler) handler would contain supporting
facilities alongside the standard functionality
described above - Ex processing similar cases in batch processing
a series of successive tasks for a case
15Worklist Handler
16Invoked Applications
- Interactive application (ex. word, excel)
- Fully-automatic application (ex. calculation)
17Administration and Monitoring Tools
- The operational management tool
- Not case-related (resource-related or
system-related) - addition or removal of staff
- input/revision of an employee's details (name,
address, telephone number, role, organizational
unit, authorization and availability). - Case-related
- inspection of the logistical state of a case
- manipulation of the logistical state of a case
due to problems and exceptional circumstances.
18Administration and Monitoring Tools
- The recording and reporting tool
- These are historical data which may be useful for
management. For example, the following
interesting performance indicators may be
distilled from the data - average completion time for a case
- average waiting time and processing time
(possibly subdivided per task) - percentage of cases completed within a fixed
standard period - average level of resource capacity utilization.
19Components of a Workflow System
20Users of a Workflow Management System
21Roles of people involved
- Workflow management system
- The Workflow Designer
- The Administrator
- The Process Analyst
- The Employee
- Applications
- database designers/programmers
- application designers/programmers
22Data in a workflow system
23Interfacing problems
- WFMC recognizes five interfaces
- Improve the exchange of data.
- Create links between servers in a simple way.
- Applications are entirely independent of the
workflow management system. - Every interface will be achieved using
Application Programming Interface (API).
24Interfacing problems (cont.)
- Interface 1
- Connect/disconnect
- Process definitions and resource classifications
- Opening, creating and saving a process
definition
- Interface 5
- Management
- Addition of an employee
- Permission of authorization
- Execution of a process definition
- Track
- Waiting times
- Completion times
- Processing times
- Routing
- Staff utilization
Interface 4 Other Workflow Enactment Services
- Interface 2
- Connect/disconnect production of case
- Work item state summaries
- Generation of new cases
- Beginning, interruption and completion of
activities
- Interface 3
- Application is opened from the system through
interface 3. (also can opened from the worklist
handler)
25Interfacing problems (cont.)
An application can be started by an engine and/or
from a worklist handler.
An application is called to perform a task.
If the workflow engine does not become accessible
following the execution of the Application due to
a system error, the engine and the application
will be 'out of synch.
Once the system has been corrected, the engine
will have no choice but to roll back the task.
26Interfacing problems (cont.)
- Atomicity
- Completed in full (Commit).
- Restarts from the very beginning (Rollback).
- Consistency
- The result of an activity leads to a consistent
state. - Isolation
- Tasks performed at the same time must not
influence one another. - Durability
- Task is successfully completed.
- The result must be saved.
- Completed with a commit.
27Interfacing problems (cont.)
- In the financial world, we frequently have to
pass the ACID test. - Linking two or more workflow systems, most of
the workflow management systems is not always
entirely clear what the state of a case is.
28Required Technical Infrastructure
- Most workflow system operate within a
client/server environment. - Client
- Worklist handler
- User Interface
- Application
- Server
- Workflow engine
- Application
- DBMS
- Application data
29Required Technical Infrastructure
30Current Generation of Workflow Product
- Product in 2000?200 suppliers
- The number of workflow systems actually in
production is relatively limited. - Why?
- The technology is quite new.
- Resulting in limited functionality and
unsatisfactory reliability.
31Current Generation of Workflow Product
- Staffware
- Graphical Workflow Definer (GWD)
- Graphical Form Designer (GFD)
- Work Queue Manager (WQM)
- Staffware Server (SS)
- Staffware Administration Managers (SAM)
- Audit Trail (AT)
32Current Generation of Workflow Product
- GWD
- The tasks are called steps.
- Automatic steps
- Normal steps
- Event steps
- Semantics
- Step
- OR-join/AND-split
- Wait
- AND-join/AND-split
33Current Generation of Workflow Product
- Condition
- OR-split? two choice
- Compare with Petri net
- Concepts such as AND/OR-split/join play an
important role in both types of models. - One of the core differences is the fact that the
notion of states.
34COSA
- COSAR
- is produced by Software-Ley GmbH.
- It is a workflow management system based upon
Petri nets. - COSA can be described as a traditional workflow
management system that closely follows the WFMC
reference model.
35ActionWorkflow
- ActionWorkflowR is produced by Action
Technologies Inc., and focuses upon supporting
processes in which communication between people
and/or parties plays a major role. - Unlike COSA and Staffware, which concentrate upon
the process, ActionWorkflow centers on
coordination. - ActionWorkflow uses so-called Business Process
Maps (BPM). - Each workflow corresponds with a transaction that
passes through the following stages - (1) preparation
- (2) negotiation
- (3) performance
- (4) completion
36ActionWorkflow(cont.)
- ActionWorkflow is only available for a limited
range of platforms. - COSA is traditional and thorough, enabling the
support of most routine production processes
within administrative organizations. - ActionWorkflow differs in many respects from
standard workflow management system, and appears
to be best suited to supporting processes in
which coordination is crucial.
37Analysis tools
38Analysis tools
- Woflan (WOrkFlow Analyzer) is a tool that
analyzes workflow process definitions specified
in terms of Petri nets. - Todays workflow management systems do not verify
the correctness of workflow process definitions. - Therefore errors made at design time such as
deadlocks and livelocks may remain undetected. - To avoid these costly problems, it is important
to verify the correctness of a workflow process
definition before it becomes operational.
39Analysis tools (cont.)
- Woflan takes a workflow process definition
imported from some workflow product, translates
it into a Petri net, and tells whether or not the
net is a sound workflow net. - Using some standard Petri-net analysis techniques
as well as those tailored to workflow nets, the
tool provides diagnostic information about the
net in case it is not a sound workflow net.
40Selecting a workflow management system
- The selection process begins with the listing of
the requirements which the system must meet.
Based upon these, a shortlist is then compiled. - One way to quickly gain a good impression of a
workflow management system is to work through a
sample process chosen in advance. - The sample process is representative of the
relevant business processes. - Once the workflow management systems on the
shortlist have been put on trial in this way, it
usually becomes clear which package is the best
choice.
41Exercises
- 5.2(a,b)
- Present the future prospects for WFMS in terms of
7 areas of functionality