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Workflow management systems (WFMS) are enjoying increasing popular­ ity due to their ability to coordinate and streamline complex organizational processes within organizations of all sizes. Organizational processes are de­ scriptions of an organization's activities engineered to fulfill its mission such as completing a business contract or satisfying a specific customer request. Gaining control of these processes allows an organization to reengineer and improve each process or adapt them to changing requirements. The goal of WFMSs is to manage these organizational processes and coordinate their execution. was demonstrated in the first half The high degree of interest in WFMSs of the 1990s by a significant increase in the number of commercial products (once estimated to about 250) and the estimated market size (in combined $2 billion in 1996. Ensuing maturity product sales and services) of about is demonstrated by consolidations during the last year. Ranging from mere e-mail based calendar tools and flow charting tools to very sophisticated inte­ grated development environments for distributed enterprise-wide applications and systems to support programming in the large, these products are finding an eager market and opening up important research and development op­ portunities. In spite of their early success in the market place, however, the current generation of systems can benefit from further research and develop­ ment, especially for increasingly complex and mission-critical applications.



Workflow Management: State of the Art Versus State of the Products

It has been over ten years since the first workflow product was introduced. Despite the large number of workflow vendors and various research efforts all over the world, as well as the hype about the workflow market, workflow technology is still far from pervasive. This paper assesses the situation from a technical point of view, focusing on the development and enactment aspects of workflow processes. We discuss the current capabilities of workflow products, major issues that need to be addressed before workflow can be pervasive, as well as possible future trends and research that will help workflow succeed.
Ahmed Elmagarmid, Weimin Du

A Distributed Workflow and Product Data Management Application for the Construction of Large Scale Scientific Apparatus

Recently there has been much discussion about workflow management for computer-based systems. Workflow management allows business managers to coordinate and schedule activities of organisations to optimise the flow of information or operations between the resources of the organisation. Scientific and engineering applications are also being viewed as potential areas in which the principles of workflow management can be applied. Scientific applications, however, present particular problems of workflow management. Not only do the workflow definitions change frequently [VWW96, ER95] but their refinement may only take place as a result of experimentation as the workflow process itself is followed. For these reasons and others commercial workflow management systems appear to be inadequate for the purposes of managing scientific workflow management applications.
The construction of large scale scientific and engineering systems necessitates the use of complex production management operations. The coordination of these operations can be difficult, particularly if the operations are distributed over many geographically separated institutes. In these environments there can be severe constraints both of time and budget so that controlled management of the inherent workflow processes becomes paramount. One example of this scientific development process is the construction of high precision scientific apparatus for high energy physics such as the Compact Muon Solenoid experiment [CMS95] (CMS) currently being undertaken for CERN, the European Centre for Particle Physics research. The construction of CMS is long scale (1998-2004), heavily constrained by resource availability and allocation and very state-of-the-art in nature. A research and development project, entitled CRISTAL (Cooperating Repositories and an Information System for Tracking Assembly Lifecycles) [LeG96], has been initiated to facilitate the management of the engineering data collected at each stage of production of CMS components. This paper reports on the aspects of scientific workflow management and product data management and the interface between the two which have been identified as being central to the assembly and production of the CMS detector.
R. McClatchey, J-M. Le Goff, N. Baker, W. Harris, Z. Kovacs

Workflow Applications to Research Agenda: Scalable and Dynamic Work Coordination and Collaboration Systems

A workflow is an activity involving the coordinated execution of multiple tasks performed by different processing entities [KS 95]. These tasks could be manual, or automated, either created specifically for the purpose of the workflow application being developed, or possibly already existing as legacy programs A workflow process is an automated organizational process involving both human (manual) and automated tasks.
Amit Sheth, Krys J. Kochut

Design and Implementation of a Distributed Workflow Management System: METUFlow

Workflows are activities involving the coordinated execution of multiple tasks performed by different processing entities, mostly in distributed heterogeneous environments which are very common in enterprises of even moderate complexity. Centralized workflow systems fall short to meet the demands of such environments.
This paper describes the design and implementation of a distributed workflow management system, namely, METUFIow. The main contribution of this prototype is to provide a truly distributed execution environment, where the scheduler, the history manager and the worklist manager of the system are fully distributed giving rise to failure resiliency and increased performance.
Asuman Dogac, Esin Gokkoca, Sena Arpinar, Pinar Koksal, Ibrahim Cingil, Budak Arpinar, Nesime Tatbul, Pinar Karagoz, Ugur Halici, Mehmet Altinel

HP Workflow Research: Past, Present, and Future

Workflow research at HP Labs has evolved through three stages during the past four years. Our effort started with the enhancement of an existing HP workflow product — WorkManager. Then, based on customers’ feedback, a new workflow prototype was developed to support the requirements of enterprise complex business process management. This formed the base for HPs second generation workflow product — AdminFlow. We are now exploring the third generation of workflow system that supports the Internet computing paradigm.
Ming-Chien Shan, Jim Davis, Weimin Du, Ying Huang

Reducing Escalation-Related Costs in WFMSs

Escalations refer to the actions taken when workflow activities miss their deadlines. Typically, escalations increase the cost of business processes due to the execution of additional activities, the compensation of finished activities, or the intervention of highly-paid workers. In this paper, we present two techniques for reducing costs related to escalations; namely, dynamic deadline adjustment and preemptive escalation. The former mechanism uses the slack accumulated during process execution to adjust the deadlines of the remaining activities, i.e., delay escalations. The latter mechanism predicts whether a process is going to escalate at some future point, and it decides whether and when to force escalation at an early stage during execution. Preliminary experimental results show the effectiveness of our techniques.
Euthimios Panagos, Michael Rabinovich

The Workflow Management System Panta Rhei

We present the prototypical workflow management system Panta Rhei which was designed to support various types of workflows in an uniform and elegant way. The main characteristics of this system are its flexibility, the lean architecture, the integration in the Web, the transactional features and its support of process management. We discuss the basic concepts of the system, its architecture and its implementation.
Johann Eder, Herbert Groiss, Walter Liebhart

The WASA Approach to Workflow Management for Scientific Applications

Workflow management has gained increasing attention recently, since it allows one to combine a data-oriented view on applications, which is the traditional one for an information system, with a process-oriented one in which activities and their occurrences over time are modeled and supported properly. While workflow management has mostly been considered in business applications so far, the focus of the WASA project is on scientific applications such as geoprocessing, molecular biology, or laboratory environments. In particular, WASA aims at flexible and platform-independent workflow support, with respect to both specification and execution of workflows. It turns out that the modeling and execution of workflows in traditional and in scientific applications exhibit significant differences. In particular, the need for dynamic modifications of workflow models while workflows are running is an important feature in scientific applications. Observations like these have resulted in a generic WASA architecture, which can be tailored towards various specific application domains. The conceptual design and functionality of a WASA prototype is outlined, in particular that of its core workflow engine, and it is shown how the requirements of flexibility in modeling and executing workflows, imposed by scientific applications, are met by this prototype.
Gottfried Vossen, Mathias Weske

Security Enforcement in Activity Management Systems

Security enforcement is an issue of paramount importance for any system that facilitates computer supported cooperative work. An activity management system is a software that facilitates specification and decomposition, and execution of activities. An activity is a set of coordinated tasks (atomic activities). The focus of this paper is on supporting security in activity management systems. In particular, we present an architecture, and describe the mechanisms that need to be incorporated for enforcing security for activity specification and decomposition, and during activity execution. This paper provides a task-centered approach towards security enforcement, wherein, the security constraints are checked and the task is allowed to be executed only if none of the security constraints are violated. This is handled by the event-condition-action rule paradigm from active database systems.
Kamalakar Karlapalem, Patrick C. K. Hung

Towards a Platform for Distributed Application Development

This paper describes the architecture of a generic platform for building distributed systems over stand alone applications. The proposed platform integrates ideas and technology from areas such as distributed and parallel databases, transaction processing systems, and workflow management. The main contribution of this research effort is to propose a “kernel” system providing the “essentials” for distributed processing and to show the important role database technology may play in supporting such functionality. These include a powerful process management environment, created as a generalization of workflow ideas and incorporating transactional notions such as spheres of isolation, atomicity, and persistence and a transactional engine enforcing these “quality guarantees” based on the nested and multi-level models. It also includes a tool-kit providing externalized database functionality enabling physical database design over heterogeneous data repositories. The potential of the proposed platform is demonstrated by several concrete applications currently being developed.
Gustavo Alonso, Claus Hagen, Hans-Jörg Schek, Markus Tresch

The Integration of Workflow Systems and Collaboration Tools

The design and development of computer support for work environments must consider both the coordination of individual activities and the collaboration that occurs among individuals in organizations. This paper presents our research efforts towards the understanding, design and implementation of a technological framework designated by “augmented work environments”. These efforts build bridges between computational support for formal processes in organizational work (workflow) and computational support for interactive and informal processes (collaborative tools for group facilitation, decision or negotiation).
Nuno Guimarães, Pedro Antunes, Ana Paula Pereira

Interoperability in Large-Scale Distributed Information Delivery Systems

In this paper we address interoperability issues in large-scale distributed information delivery systems. Architecturally, we classify existing approaches and systems into two paradigms: Multidatabase management-based paradigm and Mediator-based information delivery paradigm, and analyze the techniques used in each. Technically, we describe a number of data delivery characteristics in terms of delivery protocols, delivery modes, and delivery frequencies. We further use these characteristics to discuss and compare several data delivery schemes. We argue that an advanced distributed information system must incorporate different types of information delivery so that the system can be optimized according to various criteria, such as network traffic and heterogeneity and constant evolution of online information sources. To illustrate the architectural and technical aspects of distributed information delivery systems, we review a number of research prototypes to demonstrate the various implementation approaches used in practice, and the different solutions to the interoperability issues addressed in the paper.
Ling Liu, Ling Ling Yan, M. Tamer Özsu

Enterprise-Wide Workflow Management Based on State and Activity Charts

This paper presents an approach towards the specification, verification, and distributed execution of workflows based on state and activity charts. The formal foundation of state and activity charts is exploited at three levels. At the specification level, the formalism enforces precise descriptions of business processes while also allowing subsequent refinements. In addition, precise specifications based on other methods can be automatically converted into state and activity charts. At the level of verification, state charts are amenable to the efficient method of model checking, in order to verify particularly critical workflow properties. Finally, at the execution level, a state chart specification forms the basis for the automatic generation of modules that can be directly executed in a distributed manner. Within the MENTOR project, a coherent prototype system has been built that comprises all three levels: specification, verification, and distributed execution.
Peter Muth, Dirk Wodtke, Jeanine Weissenfels, Gerhard Weikum, Angelika Kotz Dittrich

Transactional Support for Cooperative Applications

Cooperative work on shared, persistent data requires computing system support to coordinate the work of multiple users and to ensure data consistency. Conventional database transaction models do not meet the requirements of cooperative applications. Isolation of transactions, as guaranteed by the ACID properties, contradicts the need of cooperation between users. In this paper, we investigate different advanced transaction models that target at improved support for cooperative applications. To that extent we analyze typical cooperative application scenarios and derive from that basic requirements for consistent access to shared databases. In particular we discuss in detail the cooperative transaction model that has been developed within the TRANSCOOP project. This model supports alternating periods of individual and joint work, and allows to exchange and share information consistently. It provides transactional execution guarantees both for the work of single users and for the overall cooperative effort. The model is applicable to a wide spectrum of cooperative applications ranging from creative design applications to structured workflow-like applications.
Jürgen Wäsch, Karl Aberer, Erich J. Neuhold

Migrating Workflows

In this paper we present the concept of migrating workflows, and the considerations related to the implementation of this concept. Migrating workflows are a computational metaphor for the way most people conduct their daily business: they visit a place, use a service (perhaps after some negotiation), and move on to the next place. A migrating workflow behaves similarly: it transfers its code (specification) and its execution state to a site, negotiates a service to be executed on its behalf, receives the results, and moves on. Dialog between the workflow and individual sites may influence the workflow’s migration. Thus the actual workflow instance is defined during run-time, as an effect of merging the static workflow specification and the local site rules and policies.
Andrzej Cichocki, Marek Rusinkiewicz

Technology and Tools for Comprehensive Business Process Lifecycle Management

Business processes are collections of one or more linked activities which realize a business objective or policy goal, such as fulfilling a business contract, and/or satisfying a specific customer need. The lifecycle of a business process involves everything from capturing the process in a computerized representation to automating the process. This typically includes specific steps for measuring, evaluating, and improving the process. Currently, commercially available workflow management systems (WFMSs) and business process modeling tools (BPMTs) provide for complementary aspects of business process lifecycle management. Furthermore, new concepts and interoperating tools in these categories are emerging to provide comprehensive support for managing the entire business process lifecycle. In this paper we provide an overview and an evaluation of the process modeling, analysis, automation, and coordination capabilities provided by integrated BPMTs and WFMSs. We also discuss how state of the art WFMSs and BPMTs can interoperate to provide complete support for the entire business process lifecycle. Although we occasionally discuss research issues, we mainly focus on the state of the art in commercially available technology.
Dimitrios Georgakopoulos, Aphrodite Tsalgatidou

Recent Trends in Workflow Management Products, Standards and Research

In the last few years, workflow management (WFM) has been the focus of intense activity in terms of products, standards and research work worldwide. Work in many areas of computer science impacts workflow management. Many workflow companies and research groups are in existence now. Several conferences and workshops are being held regularly. In this paper, I briefly summarize the recent trends in WFM products, standards and research. I address technical as well as business trends.
C. Mohan

Kerem — Reasoning About the Design of Partially Cooperative Systems

Inter dependencies among information systems is required by a growing number of applications. Partial cooperation occurs when a collection of independent systems have some forms of inter dependencies. These inter dependencies may take a diversity of forms, and various levels of complexity. This paper introduces the Kerem model which serves as a modeling and reasoning tool for partially cooperative systems. The paper presents the two main features of Kerem: the modeling tool for expressing the specification of a cooperative system, and a static analysis reasoning tool, capable of reasoning about validation diagnosis, change management, and issue ad-hoc queries about the cooperative system’s behavior.
Opher Etzion

Workflow Technologies Meet the Internet

Workflow systems are increasingly used in large enterprises for automating complex business processes, where demands are placed on high performance, continuous availability, and end-user mobility. Furthermore, the ubiquitous Internet and Intranets are rapidly becoming the distributed infrastructure over which enterprises want to deploy such services. In this paper, we discuss the opportunities provided by Internet/Intranet technologies to enhance the capabilities of a workflow system. The use of Web browser-based open clients allows users to interact with a workflow system from virtually any computer. Advanced features such as applets allow the end user to dynamically acquire workflow applications and tools. In contrast to existing workflow systems, which have monolithic “workflow engines” and system specific server/client connections, we propose an architecture consisting of distributed, dynamically configurable server components, interacting with one other through messages. Redundant workflow servers can be easily added to meet load demand and to provide high availability. Finally, for inter-enterprise processes (such as those arising in electronic commerce), we describe techniques that facilitate cooperation and synchronization across process boundaries without compromising security or autonomy.
Umeshwar Dayal, Qiming Chen, Tak W. Yan

Workflow Reuse and Semantic Interoperation Issues

Workflow specification is a complex construct highly integrated (correlated) with specifications of other types. Designing a workflow we should consider semantics of workflow objects and objects related to them in an integrated way.
Reusable components are treated semantically interoperable in context of a specific application. For components and for specification of requirements canonical object model semantics and ontological semantics are considered jointly to provide complete specifications
In frame of complete specifications, a notion of the most common reduct for a pair of type specifications is introduced as the basis for detection of reusable fragments. This notion is based on a refinement technique. An approach for component-based design with reuse is outlined.
The multiactivity (workflow) canonical specification framework is defined. The notion of workflow refinement is based on systematic analysis of functional and concurrent workflow specification properties merging conventional well grounded specification refinement technique with determining of process bisimulation equivalence.
A simple example showing a uniform representation of heterogeneous workflow specifications in the canonical model is introduced. The example is used to show how common workflow reducts can be identified and composed in process of the information system development.
Leonid Kalinichenko


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