Workflow on the Web: Integrating E-Commerce
And Business Process Management
Authors' Names, Affiliations, Mailing addresses: Gregory Mentzas
Assistant Professor,
Department of Electrical and Computer Engineering National Technical University of Athens,
42, 28th October str., 10682 Athens, Greece, email: [email protected]
Christos Halaris
Department of Electrical and Computer Engineering National Technical University of Athens,
42, 28th October str., 10682 Athens, Greece, email: [email protected]
INTRODUCTION
The dynamic development of Information Technology during the last years resulted in major reforms of the traditional business environment and the way business is performed. Spearhead of this transformation is the continuous spread of the Internet whose users over the world will probably reach 1 billion in the next ten years.
This wide spread is already offering to enterprises the ability of direct contact and electronic transactions with clients throughout the world, often resulting to dramatic cost decreases and impacting severely the way enterprises seek for competitive advantage. As a consequence Internet’s role has been enlarged from a global communication vehicle to a key platform for global business development.
Although E-Commerce provides new useful ways for promotion and transactions, there are many relevant activities performed in the back office especially in the case of business to business transactions. For example when the client is ready to buy a product from a company’s web site the company should check the availability of the product, and then inform sales department to produce an invoice, arrange shipment details, etc. This means that a company has to combine successfully the new Internet based activities with traditional activities performed internally.
In this context the integration of both intranet and internet based activities in an automated information system would create important competitive advantage for the company enabling quick response to the client’s wishes and better process management.
Towards this direction a company’s technology infrastructure could build on Web Based Workflow Management Systems (WfMS). Web based WfMS are the evolution of traditional WfMS that support the automation of processes within a company.
WHAT is WORKFLOW MANAGEMENT?
The workflow concept has evolved from the notion of the process in manufacturing and the office. Such processes have existed since industrialisation and are the result of seeking to increase efficiency routine work activities. According to the workflow approach work activities are separated into well-defined tasks, roles (task performers) and rules, which all together create a process.
More explicitly the term workflow can be defined as the complete or partial automation of relevant tasks performed by people, machines or a combination, that all together create a business process. According to the Workflow Management Coalition1 Glossary Workflow stands for the automation of a business process in whole or part, during which documents, information or tasks are passed from one participant to another according to a set of procedural rules. [WFC}
According to the same source a Workflow Management System (WfMS) is a system that defines, creates and manages the execution of workflows through the use of software. This software is running on one or more workflow engines, which are able to interpret the process definition, interact with workflow participants and where required invoke appropriate IT tools and applications.
This means that a WfMS, according to the defined processes and roles, delivers work items to the defined users, and supports work performance by invoking appropriate applications and utilities. In addition the system provides the ability of monitoring the progress of the tasks through the process and generates statistics on how well the different steps of the process are doing.
1
The Workflow Management Coalition, is a non-profit, international organisation of workflow vendors, users and analysts. The Coalition’s mission is to promote the use of workflow through
We can consequently distinguish three functional levels for WfMS, which are:
•
the Process definition level , concerned with defining, and possibly modelling, the workflow process and its constituent activities•
the Run-time control level concerned with managing the workflow processes in an operational environment and sequencing the various activities to be handled as part of each process•
the Run-time interaction level with human users and IT application tools for processing the various activity stepsAll the above is incorporated in the Workflow Management Coalition’s Reference Model presented in figure 1 P r o c e s s Definition Tools Administration & M o n i t o r i n g Tools Interface 1 Interface 4 Interface 5
Workflow Enactment Service W o r k f l o w A P I a n d I n t e r c h a n g e f o r m a t s Other Workflow Enactment Service(s) Workflow Client A p p l i c a t i o n s Interface 3 Interface 2 Workflow E n g i n e ( s ) WorkflowE n g i n e ( s ) I n v o k e d A p p l i c a t i o n s
Figure 1: Workflow Management Coalition’s Reference Model
The Process Definition Tools are software components used to translate a business process from the real world into a formal, computer prosecutable definition. Information provided includes mainly the actors that perform the tasks, the routing of the activities and the relevant rules and conditions of execution.
The Workflow Enactment Service provides the run-time environment and is responsible for the enactment of the processes utilising one or more Workflow Engines. The Workflow
the establishment of standards for software terminology, interoperability and connectivity between workflow products.
Engines interpret and activate part, or all, of the process definition and interact with the external resources necessary to process the various activities.
The interface around the Workflow Enactment Service is designated WAPI - Workflow APIs and Interchange formats, which may be considered as a set of constructs by which the services of the workflow system may be accessed and which regulate the interactions between the workflow control software and other system components. Many of the functions within the 5 interface areas are common to two or more interface services hence it is more appropriate to consider WAPI as a unified service interface which is used to support workflow management functions across the 5 functional areas, rather than 5 individual interfaces.
BASIC TYPES OF WORKFLOW SYSTEMS
There are many different ways of viewing workflow products, their capabilities, and their applicability to improving different types of business activities. A widely accepted taxonomy distinguishes between administrative, ad hoc, collaborative and production workflow. The basic parameters of this classification are the similarities among the business processes involved and their value to the associated enterprises. However, it is also possible to organise them according to the task complexity and the task structure. Figure 2 summarises both approaches. Production Collaborative Ad Hoc Administrative Repetitive Process Unique Process Business value High Copmlex Administrative Ad Hoc Collaborative Production Task Structure Low High Task complexity Simple Figure 2: Type s of WfMs
In general, administrative WfMS refer to bureaucratic processes where the steps to follow are well established and are based on rules known by all participants. Examples are the registration for courses in a university, applying for a degree after finishing the dissertation,
registration of a vehicle, and almost any other process in which there is a set of forms to be filled and routed through a series of steps. Note that this type of workflows leads almost naturally to the idea of form processing, a new term for the older concept of the paperless office, and is also associated with large scale systems where the number of processes involved tend to be very high. For instance, a typical billing application may involve several million processes a year.
Ad hoc workflows address exceptions and unique situations. It may also be the case that the situation is not exceptional but each particular instance is unique. For example, each journal follows a different protocol for the submission process. Authors, especially given the length in time of these processes, may want to leave the co-ordination of the different steps in the hands of an ad hoc workflow system. This brings an important aspect of ad hoc workflows. While the actual process may be unique, the user will in general be involved in a variety of these processes. The reason for using a workflow system with these characteristics is not the difficulty of tracking each separate process, but the problem of keeping track of all of them simultaneously.
The third class of workflows, collaborative, is mainly characterised by the number of participants involved and the interactions between them. Unlike other type of workflows, which are based on the premise that there is always forward progress, a collaborative workflow may involve several iterations over the same step until some form of agreement has been reached or it may even involve going back to an earlier stage. A good example is the writing of a paper by several authors. It would be very difficult to model such a process using tools that are not geared for collaboration since it is almost impossible to predefine the steps to follow. Moreover, collaborative workflows tend to be very dynamic in the sense that they are defined as they progress. Taken to the extreme, it may be questionable whether this type of progresses are in fact workflow systems since most of the co-ordination is done by humans with the system limited to the role of providing a good interface for recording their interactions.
Production workflows are the high end of these systems. They can be characterised as the implementation of mission critical business processes, i.e., those directly related to the function of the organisation. Credit and loan applications and insurance claims are the typical examples. However, the difference between administrative and production workflows is sometimes a matter of perspective. Usually, when talking about production workflows, the main points to consider are the large scale, the complexity and the heterogeneity of the environment where
they are executed, the variety of people and organisations involved, and the nature of tasks. In particular, production workflows tend to be executed over heterogeneous systems, frequently legacy applications, and it is crucial to have monitoring tools to allow the statistical analysis of the execution of these processes.
Another classification often found in the literature is based on the underlying technology: mail-centric, document-centric, and process-centric. Mail-centric systems are based on electronic mail and can be roughly associated with collaborative and ad hoc workflows. Given the characteristics of the communication media used, e-mail, these systems are not for production workflows or environments with a large number of processes. Document-centric
systems are based on the idea of routing documents and the ability to interact with external applications is limited. Many administrative workflows, those based on forms, can be implemented using document-centred systems. Process-based systems correspond to production workflows. They generally implement their own communication mechanisms, are built on top of databases and provide a wide range of interfaces to allow interaction with legacy and new applications.
WEB BASED WORKFLOW ARCHITECTURE
Web based WfMS are the evolution of traditional workflow systems. They provide the ability to automate processes, parts of which are initiated or performed by users via a web browser. Overcoming the traditional intranet’s client-server architecture web based WfMS combine the abilities of Internet with workflow technology by introducing a 4 layer architecture (Browser/client, Web Server, Workflow Server and Relational Databases). Figure 4 shows the Web components integrated into a full-blown workflow system.
Internet Browser Browser Browser UNIX PC MAC HTTP Server Workflow App Server Process Manager Messaging SQL Server Directory Services Document Database LOB/ Legacy Data Bus.Process Defs Names and Roles Transaction Queue Performance Archive
Figure 4: Web based Workflow Architecture (Source techguide.com)
In this schematic, we see three Browsers that are on different disparate platforms, such as a Macintosh, PC, and UNIX workstation, connected to a Web server over the Internet (or Intranet). All the user needs to connect is a Browser capable of working with the latest HTML standards.
All the information about the routing of the work items, the rules that govern that routing and the roles that perform the workflow tasks are stored in relational databases. As shown in Figure 4, the connection between the Web server and a set of relational databases is made via an application server that ties into a SQL server containing the workflow data. The Process Manager manages the SQL server and consequently the process definitions, the names of the participants in the workflow and the rules which govern their participation, as well as a transaction queue and performance tracking database.
The organisation’s workflow routes are codified using the business process definitions. It is here that all the definitions of all the processes, which co-ordinate the organisation’s business output are stored. Names and roles are stored in a database which defines what each member
has the right to do and which specific actions should be assigned to that individual. In order to allow a rollback to a previously known and valid transaction and restart the process, a transaction log is required in case of any missed or interrupted transactions.
The Process Manager is the heart of the system and uses the information in the stored databases to affect the desired process activity on behalf of the organisation. It is the Process Manager who applies the rules to the process flows and performs the co-ordination of activities among the actors in the system, validating security and access rights, managing exceptions to the standard flow based on defined rules, and so on.
The document database will contain all of the documents required to perform the activities defined in the processes. Additionally, there is a forms database which contains the forms required for the different kinds of transactions used by the organisation. There are three kinds of forms that are needed to create a complete “Web workflow application.” They are Initiation forms, Status and interaction forms, and Work List forms. These forms are filled in by users with information pertinent to desired activities, such as logins, requests for documents, etc. They are also used by the system to transmit required information in the appropriate areas back to the users. These forms act as the carriers of structured information between the process manager and the users and become a key element of the architecture.
Figure 4 does not show the tools required to define and build the process definitions for the system. Workflow implementations are seldom an “off the shelf” fit with any organisation, simply because of the unique and individual characteristics of each organisation. Those tools are usually part of a WfMS and include a number of templates and process models, which however can be considerably easily modified.
Also, a set of administrative tools is required to maintain the process definitions once they have been established. Adding and deleting users, assigning and changing passwords, building and modifying the document structures and their interlocking hyperlinks are all critical administrative tasks which need to be facilitated within the above architecture.
OPERATION of WEB-BASED WfMS
There are three distinct ways of interacting and using workflow technology on the World Wide Web:
1. Initiating workflows – where a casual user may see something they wish to buy advertised on a Web page, or filling in, for example, an insurance claim form. Once the user has entered the required information, a workflow procedure will be initiated and handled by others. The initiator will have no further part in the process – except at the end where some information, goods or payment is sent to the originator. This is identical to sending a request or information via normal mail.
2. Full participation – where a known user (registered on the system) can take part in the full business process. The user can select procedures to start (depending on access rights), will have work sent to them via the procedure which they have to action and complete and they can access the audit trails and management information.
3. The third scenario is essentially a combination of 1&2 above. It involves those instances where a casual user initiates a procedure, but, as a result of their action, becomes part of the full business process.
In order to start the operation of the system the definition of processes has to be complete. As mentioned before Process definition consists on defining of routes, performers, and rules as well as on designing the forms required and mapping documents and applications to be used. This stage is completed by assigning passwords and establishing appropriate security and the system is ready to be used.
The system begins when a Web browser initiates a workflow application. First, each user logs into the work management environment by accessing a specific URL. Using a logon form, the user is prompted to enter his name and password. Following the completed form is sent back to the Web server. The Web server receives the HTTP message earmarked for that specific URL, launches the work management environment and passes input data items as name-value pairs. Accepted transactions go to the next step, while rejected logons are given an error message.
Each user accesses a single place where they can view and manage work, and see a list of applications in which the user is allowed to participate. The server processes the list with user’s work items, including those from personal work, group projects, and structured business processes. Appropriate work items for this user will be validated by the Process Manager, which also determines the validity of each action dependent on the user’s role, the rules
applied to that role, and the process definition. The merged form with the specific user data is then posted back to the requesting user via the http server, and the loop is closed.
To initiate a business process, the user selects an application and an initiation form is presented. The initiation form is a “document” that contains all the information from various sources such as line-of-business and workflow databases, needed at this juncture of the business process. Once the user has completed the form, it is submitted to the workflow application server. The business process is viewed and interacted with from within the user’s work place.
From there, the Process Manager tracks and manages all the steps in the business process according to the defined rules and moves the process toward completion by sending e-mail reminders to participants, or escalating action (steps to participants). In addition, the Process Manager maintains a record of the entire business process to allow, among other things, the ability to monitor and analyse business process performance.
WORKFLOW ON THE WEB AND CUSTOMER ORIENTATION
Web based WfMS can be applied in order to automate customer-oriented business processes over the Web. Depending on the organisation, customers could be internal staff of the organisation, consumers consumer transactions) or a business entity (business-to-business transactions).
When integrated into customer oriented applications, web based WfMS create a new platform of communication and interaction, whic h is a faster and easier than traditional forms such as postal mail and telephone. WfMS are able to manage all types of traditional documents as well as of the new non-traditional digital forms of information, such as voice messages, e-mails, video, and Web pages, as input into a workflow process.
For business to business transactions, web based WfMS provides many advantages. Extranets, which consist of networks among trading partners using the Internet as the network infrastructure, are going to pave the way for extended Web-based workflow applications between organisations with dissimilar computing system environments. Using the Internet’s infrastructure, the extranet will connect the business processes of both the customer and the supplier.
One of the first implementations of network-based workflow between trading partners was Electronic Document Interchange or EDI. EDI is a technology that allows trading partners to send data from one computer system to another. This concept has proven beneficial to many companies. Orders can be sent directly from a customer’s purchase order system to the completely different order entry system of the vendor with no human intervention (see Figure 5). This form of business communication is also a form of workflow. As much as there are upsides to traditional EDI solutions, there are also downsides. Traditional EDI implementations are costly. The Internet-enabled supply chain between business partners is expected to change this. Internet Trading Data Trading Data Internet Standards Internet Standards ERP Company A ERP Company B
Figure 5: Electronic Business to business transactions (Source techguide.com)
Extranet solutions using workflow on the Web will be simpler than EDI in many ways. Using the Web, business partners will be able to share not only data among dissimilar systems but will be able to share documents, too.
Workflow technologies allow companies to extend their organisational boundaries to seamlessly include their customers and suppliers. Consequently a work item can move through multiple organisations linked over the Internet to achieve the required goal. In addition, authorised users can track workflow activity through the various heterogeneous organisations from their desktop.
In the next pages we present the most common, commercially available web based workflow products. It should be noted that we concentrated on studying indicative workflow products that operate over the Web and not every WfMS available on the market. This section describes the following workflow management systems:
• Ultimus’s Ultimus
• Action Technologies’ ActionWorks Metro
• Lotus’s Lotus Notes
• Open Text Corp.’s Open Text Livelink Intranet Suite 7
• InConcert Inc.’s InConcert Workflow
• FileNet Corp.’s Panagon Visual WorkFlo
• Keyfile Corp.’s Keyflow
• Optika’s PowerFlow
• JetForm’s InTempo
• Staffware’s Staffware Global
• TeamWARE’s TeamWARE Flow
Ultimus
Ultimus is an Intranet/Internet (Web) based, client-server application targeted at business workflow automation. It provides a means of developing and deploying sophisticated workflow applications on the Web without any programming, scripting or macros. Because Ultimus relies on an Intranet as the primary transport, the application is scalable in terms of the number of users and the geographical location of the users.
Ultimus Workflow Suite includes:
• a Graphic Workflow Designer, which is an object-oriented tool used for designing the workflow processes,
• an Electronic Forms Designer for designing forms so that the users can interface with the process via a graphical user interface, and
• “Workflow Robots” (Flobots) that allow a process to interact with third-party applications such as spreadsheets, databases, word processors and use them for accomplishing the tasks of a process.
Ultimus also allows the use of the existing databases and provides for simulation of the workflow before its installation.
ActionWorks Metro
It is a product that integrates the Web with a messaging system. Its goals are to manage the commitments people make and to provide an easy way to separate work from information items. The Metro suite offers a Web-based environment for delivering collaborative workflow process management to the enterprise. It includes:
• Process Builder for designing workflows and incorporate them into the system for structured processes.
• Action Manager who interfaces with SQL Server to provide database support for version control, reporting, tracking and archiving of workflows.
Metro can send a complete e-mail messaging package over the Internet that includes notification, status, responses, data, due dates, reply due, as well as a hot URL link. The hot URL lets the user navigate to the Web-based Metro form where they can take the next action. Rather than reply with e-mail, the user links directly to Metro and completes that step in the process.Metro is an open system and can be integrated with a number of document-management and imaging systems, as well as line-of-business applications, such as PeopleSoft and SAP R/3. Metro supports corporate database access at the client and server levels.
Lotus Notes
Lotus Notes combines Web server technology with messaging, workflow application development and document handling. It provides an open Web application server (Domino Server), Domino Enterprise Connection Services (DECS) for easy integration with backend systems, and support for Microsoft’s IIS Web Server. Domino server bridges the open networking environment of Internet standards and protocols with powerful application development facilities and delivers messaging and collaboration services (including discussions, integrated web access, calendaring and group scheduling). Domino is scalable and provides failover protection. Lotus Domino provides a set of integrated services such as, Messaging, Directory, Security, and Replication.
Open Text Livelink Intranet
Open Text Livelink Intranet is a Web-based integrated application suite for the collection, organisation and deployment of enterprisewide information, workflow management and workgroup communication. A collection of tools including shared libraries,
document-management tools, search utilities, project document-management tools and workflows combine to provide a comprehensive collaborative product. Livelink is a Web-exclusive product, that is, the only one not aligned with a messaging product.
Although Livelink does not use a messaging system to handle the flow of work, e-mail messages can be sent from Livelink telling you that a workflow step has arrived. When you click on the link in the e-mail message, Livelink is invoked, security is checked, and you are taken to the appropriate workflow (which is checked out of the Livelink Library from the relational database)
InConcert Workflow
InConcert features a three-tier client/server architecture with multiple client components. Clients are used for building the process, defining the user interface to the workflow tasks, and managing the workflow. Multiple InConcert servers can run on a single machine. A workflow process is restricted to a single server. And, in order to access different processes on different servers, users must explicitly log off one server and onto another.
InConcert servers can run on Windows NT or on a variety of Unix platforms, including SunOS, Solaris, AIX, and HP-UX. The product supports Windows (3.1, Win95, and NT) and Unix (Motif) clients. Supported RDBMSs include Sybase, Oracle and Informix.
Panagon Visual WorkFlo
Using a browser, e-mail system, or HTML form(s) tied to a workflow application FileNet’s Panagon creates an large number of scenarios in business where a process can be initiated by an office user, disconnected employee or partner, or a customer from their home. Examples include credit card applications, expense report approval, insurance claims, travel’s authorisations, home banking, home shopping etc.
Visual WorkFlo allows a standard desktop browser to create work, find a piece of work, check its status, and request updated information on that work. Visual WorkFlo Web Services is based on Java technology and supports applications running on a variety of supported platforms. The use of Java affords a high level of flexibility and scalability in choice of Web servers. Legacy software applications running on any Java-compliant platform can participate in the workflow
Keyflow for Microsoft Exchange Server
Keyflow is a collaborative workflow authoring solution based upon Microsoft Exchange Server. It expands the Exchange routing features by leveraging the messaging environment.
Keyflow takes advantage of Outlook’s or Microsoft Exchange’s client user interface, standard active messaging, user addressing, and public folder and replication facilities. Any user can initiate a workflow and respond to workflow task messages over the Internet using Outlook’s Web access. Because all work is done on the IIS server, clients do not need any extra software installed beyond a Web browser.
PowerFlow
An object-oriented solution for the problem of how to better route, manage, monitor and co-ordinate the information and processes. Procedures are mapped into the system using simple graphical tools without any programming required. Business rules and procedures can be enforced while also granting ad-hoc privileges to authorised users. Parallel processing is supported, allowing multiple workers to perform tasks on the same work item simultaneously. Management control is facilitated through tracking and reporting.
PowerFlow is built on a three-tier architecture using Windows Sockets for efficient and secure processing using the Internet. It also incorporates Internet specific features such as Web browser support, Web object support and HTML-based forms.
InTempo
InTempo uses an open architecture of HTML, Active Server pages and Java, along with traditional clients such as JetForm Filler, InTempo achieving broad applicability across any LAN or intranet IT infrastructure. InTempo uses any e-mail system for transport. Workflow tasks are in the mailbox. For users who want additional work management functionality, it offers a customisable, personal Web Worklist, which allows users to sort, view and process their workflow tasks.
InTempo is optimised for processes that involve structured information - from expense accounts and purchasing, through complex tasks such as project costing, to collaborative enterprise-wide exercises such as human resources surveys. It can also handle unstructured information, such as document review, budget approvals, policy distribution, etc.
Staffware Global
Staffware Global allows users to participate fully in automated processes by accessing the Staffware Workflow server using a Web browser or Network Computing device across the Web. It offers a good compromise between production and administrative workflow requirements while delivering production workflow throughput.
Staffware Global is a set of pure Java applets providing an environment in which a user can access all of the relevant elements with minimal swapping or downloading of applets. The definition of the processes does not require additional programming in Java, HTML or CGI.
TeamWARE Flow
It is a part of the TeamWARE groupware product suite that enables users to organise, find and share information within teams, between teams and between organisations. TeamWARE Flow provides an open development environment with published API, TCL scripting language and standard API which can be utilised in Windows and Web environments. It does not depend on any e-mail product and, for example, TeamWARE Mail, Exchange Mail or Lotus Notes can be launched from TeamWARE Flow. It supports the Workflow Management Coalition’s Workflow API (Interface 2) between the workflow server and client.
TeamWARE Flow supports processes that run in a single server and processes can be migrated from one server to another. When an organisation has multiple TeamWARE Flow servers, each running its own processes, a user can access them by logging separately into the servers.
CONCLUSIONS
Web based WfMS provide the missing link to integrate Internet’s capability to boost global business presence and handle customer and sales related applications with back office business activities and administrative tasks. This paper presented the business advantages that companies operating in the E-commerce era may have by integrating their customer oriented business processes with Web based WfMS
The automation of processes achieved, results on minimising their implementation time as well as on eliminating dead times between the different tasks of each process. Up to 90% of the total time could saved by installing a workflow system, managing for example the delivery of
an order received electronically. This means that companies will be able to enhance their reactivity to client’s demands and therefore gain a competitive advantage.
Companies could also benefit as the introduction of a workflow system eliminates most supervisory tasks. The system takes over most of the daily activity planning and assignment and sends to users a list of tasks to be performed. As a consequence a large amount of resources is deliberated and the productivity of the company would raise.
Supplementary, workflow systems provide clear detailed progress reports presenting the tasks in progress, their status and the person responsible, as well as the tasks remaining in order to complete the process. In this way Managers obtain an on time, accurate view of business performance and clients can have exact information about the stage of elaboration of their request.
In addition workflow systems contribute essentially in the areas of Quality and Cost Control. Since a workflow system maintain a detailed log, including task name, starting and finishing date and time, performer, it is possible to monitor cost evolution, spotting quality problems of customer service and managing bottlenecks.
Last but not least, the use of workflow systems increases the security of the whole system as users access ability is predefined and continuously controlled by the system. All documents to be approved are routed by the workflow engine only to authorised persons and are further processed only after been approved.
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