Collaborative Enterprise Modelling project Goals

Remigijus Gustas © Importance of Enterprise Modelling

Collaborative Enterprise Modelling project

Goals The ultimate goal of this study on enterprise engineering is to develop a unified method for collaborative

modelling and integration of the strategic, organisational and technical descriptions of enterprise architectures. Realising a future vision on collaborative enterprise engineering that can be enabled through semantic web technologies, it requires to reassess many of the existing theories, concepts and practices of knowledge-based system development, business process re-engineering and information system engineering. To deliver a collaborative vision to enterprise modelling, we need to solve a number of fundamental problems: - How can various types of enterprise architectures support traceability and management of knowledge? - How can we develop supporting technologies to rapidly re-design, evolve, compose new services and

integrate them with the overall technical system architecture? - How can we deal with the inherent complexity of the detail organisational and technical representations

and at the same time to maintain consistency with the general strategic and holistic view to business process reengineering?

Solutions to the given problems have strategic importance in the area of information technologies. New enterprise engineering methods must support traceability and management of enterprise

architectures along various perspectives and across different views. A new collaborative enterprise modelling approach is necessary to facilitate reasoning on quality of architectural solutions across organisational and technical system boundaries. Research on modelling and integration of enterprise architectures includes work on: - New theories and techniques for a graphical description and reasoning about the strategic,

organisational and technical aspects of enterprise architectures, - New methods for unambiguous representation service capabilities and new principles of quality

assessment, - New graphical approaches for enterprise modelling and integration of enterprise knowledge that is

represented on various levels of abstraction, - New techniques for computer supported composition, decomposition and re-engineering of enterprise

architectures, - New methods of the permanent change management and enterprise architecture version control that is

caused by changes in individual views, - New techniques to support and promote interaction across various perspectives and views by using

collaborative technologies, - New cost-benefit analysis techniques for the use and deployment of technical and organisational

components. Integrity of representations is essential for bridging a communication gap between managers and IT

experts, because it facilitates reasoning across organisational and technical system boundaries. Before the collaborative enterprise engineering becomes reality, there are a number of challenging problems that need to be addressed. The most important fundamental research issues include enterprise component deployment and service modelling, new service composition, evolution, integration and engineering of supporting technologies. A self-describing nature of services on the Internet and particularly the ability to define requirements for business collaborations should provide significant competitive advantages. Adopting a new service oriented paradigm as a glue for integration of enterprise modelling has the potential to reduce web-based system development complexity and costs, to lower maintenance costs, to increase e-business re-engineering efficiency and to identify new revenue streams.

The research on enterprise modelling and integration by using semantic web technologies should bring significant benefits including:

- Improving the ability of organisations to maintain enterprise architectures and to manage business knowledge in a systematic way,

- Reduce the development costs of information system applications by providing new integration techniques,


- Improve collaboration and communication within small and big companies by providing traceability of enterprise knowledge assets on different levels of abstraction, across various perspectives and views.

IT adaptation problems worldwide demonstrate that an integrated enterprise representation is necessary to understand orderly transformations from the current to the target architecture. Development of a common business and technical process modelling foundation for web service engineering is not sufficient. Additionally, to support development of collaborative business formations, enterprises have to share the pragmatic knowledge that defines intensions of various actors involved. The following fundamental research tasks are critical in this area: 1) Analysis and identification of a core set of dependencies that should serve as building blocks of the

essential architectural patterns on various levels of abstraction. The core dependencies should be propagated and rooted in the basic building constructs of the traditional approaches that define various views on organisational and technical system development solutions. Achievement of this goal should help us to identify various types of interdependencies, which would serve as glue for different perspec-tives and views on the enterprise architecture.

2) Development of the cooperative enterprise modelling approach and demonstration of its usage for enterprise engineering across organisational and technical system boundaries. This goal is especially relevant for modelling of electronic business. It should be relevant for definition of the strategic knowledge such as information about problems, opportunities and intensions of actors.

3) Definition of a consistent enterprise modelling foundation. It is necessary to define a restricted set of dependencies and inference rules, which would assist in identification of quality problems in enterprise modelling. A new modelling method should be defined in terms of the basic set of modelling constructs and their interplay with the traditional semantic dependencies that are used in UML. It should be noted that uncontrolled use of different dependency types in UML often results in contradictions among static and dynamic views.

4) Development of principles for the semantic integrity control. The intention is to concentrate on undesirable qualities such as inconsistency, incompleteness (underspecification, overspecification), incoherence and ambiguity of business process models.

5) Development of a new approach for enterprise model evolution. The most important issue in relation to this goal is definition of conceptual operations for enterprise architecture change management such as generalisation, aggregation and negation of enterprise modelling fragments.

Graphical representations of information system requirements should be useful in reengineering and assessment of the IT solutions across the organizational and technical system boundaries. The ultimate goal of the collaborative enterprise modelling approach is to introduce a unified basis for integration of enterprise architectures on different levels abstraction, in various perspectives and across different views. A new service-oriented modelling method must satisfy a number of challenging requirements. It should be adopted in the new application domain of e-business development by enforcing distributed information system application development through use of the semantic web based technologies.

State of the art: Fundamental modelling problems of Enterprise Architectures The term of Enterprise Architecture has been used for many years within information system engineering

community. It refers to various types of graphical representations that define how business, data, technology and software application structures (Spewak, 1992) are perceived from different points of view. The concept of enterprise in the context of information system development sometimes denotes a limited area of activity in organisation (Bubenko, 1993) that is of interest by a planner, owner, designer or builder of enterprise architecture. In the Nineties, the term of architecture started to be used even by business managers, especially those involved in business process re-engineering, to refer to the graphical descriptions of organisational business processes. Today, enterprise architecture or enterprise modelling can be used to denote a comprehensive graphical description of the semantic relationships across organisational and technical system boundaries. For instance, when managers are talking about the alignment of information technology (IT) systems and applications with respect to business processes, they define graphical enterprise models, which demonstrate how the alignment should be achieved. As a result of congressional legislation, governmental agencies in USA are required by law to maintain enterprise architectures (www.cio.gov).

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There are many different modelling approaches for description of enterprise architectures. The Zachman

framework (www.zifa.com) can be considered as a comprehensive guide of documents or blueprints that comprise the enterprise architecture. Typically, it is defined in various perspectives such as the "what", "who", "where", "when" and "how" (Zachman, 1996). The matrix of various representations of enterprise architectures is given below.

Data

(What) Function (How)

Network (Where)

People (Who)

Time (When)

Motivation (Why)

Scope Planner view

List of concepts

List of processes

List of locations

List of organizational units

List of business events

List of business goals

Organisational system Owner view

Entity relationship diagram

Business Process diagram

Diagram of logistic network

Organisation decomposition chart with roles

Schedule charts

Business Strategy / Plan

Information System Designer view

Logical DataArchitecture

Software application architecture

Distributed system architecture

Human interface architecture

Control structure

Constraints and rules

Technology Builder view

Physical Data architecture

Deploy-ment archi-tecture

Technology architecture

Presentation/ Layout structure

Component control structure

Rule design

Representa-tions Subcon-tractor view

Data definition

Process design

Network architecture

Interface architecture

Timing definitions

Rule specifica-tion

Functioning System

Data Compo-nents

Network Organisation Schedule Strategy

An integrated representation of the organisational and technical system is necessary to develop a holistic understanding and to plan orderly transitional processes from the current to the target enterprise architecture. There are two basic challenges facing the overall enterprise engineering process: enterprise modelling and integration (Vernadat, 1996). Modelling involves visualisation or externalisation of enterprise architectures from different points of view such as planner, owner, designer, builder and subcontractor. Modelling would involve representation and population of various cells of the Zachman Framework with instances of diagrams that represent the strategic, organisational and technical system development perspectives. It should be noted that different views and perspectives do not make the enterprise architecture. To obtain value from the graphical representations that are used in organisation by different groups of people, these documents must be integrated. The developers of enterprise engineering tools usually rely on a common repository (for instance, www.popkin.com, www.metis.no ). The key problem is that existence of a common repository does not guaranty consistency and integrity of various enterprise representations.

Many companies have been building information systems for many years, but just few of them have actually understood interdependencies among various diagrams that define distinct architecture types. The fundamental problem still remains how to maintain integrity of enterprise representations. Quite often enterprise architects have no complete agreement on the basic relationships that should be represented in various documents. This often results in wasting huge financial resources for technical system development without a significant impact. One of the major reasons of such failures is a communication gap between the management and IT development personnel. The problem resides is in a difficulty to integrate enterprise modelling views of two subcultures: business management and IT development personnel. Any change in the traditional work practice may be considered to be a symptom for a new problem. Managers and their staff do not want to be information technology experts. What they want is flexible methods for tracing their business knowledge into the information system specifications.

The traditional information system analysis and design methods are not working well enough for the achievement of that purpose. The Unified Modelling Language (UML) is intended for requirements engineering and information system modelling (Booch et al., 1999), (www.uml.org). It provides twelve

http://www.zifa.com/

http://www.popkin.com/

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standard diagram types to analyse a technical system solution. Nevertheless, the current UML foundation has some inherent integrity problems of static and behavioural aspects. Another weakness of UML is its focus on the technical system part, not on organisational system or strategic description. The underlying modelling foundation of conventional information system modelling approaches is too weak to achieve integrity and to manage evolution of enterprise architectures. Integrated enterprise models might help managers and IT experts to define, visualise, assess and trace organisational changes from one view to another. Therefore, they should be considered as a corporate resource in diagnosing potential problems. Graphical models are crucial to enable reasoning about business process integrity and the purposeful implications of an organisational change.

Enterprise engineering in the context of this project is going to deal with modelling and integration of various strategic, organisational and technical development aspects. At the same time, enterprise engineering is viewed as an extension and generalisation of the traditional system analysis and design phase. Thus, enterprise modelling and integration is taking into account the early, middle and late information system development life cycle. It should be noted that enterprise modelling could be viewed as three dimensions of requirements engineering (Pohl, 1993). The agreement dimension should be based on the basic strategic decisions and enterprise evolution processes, the representation dimension is based on the essential semantic aspects of system analysis and the specification dimension – on the implementation oriented system development aspects. The most difficult part of enterprise modelling is arriving at a coherent, complete and consistent graphical description of a new organisational and technical system. The ability to describe essential system solutions in a clear and sufficiently rich way is acknowledged as crucial in many areas including software requirements engineering, conceptual modelling, database design, business process modelling, ontology integration, knowledge representation and information system engineering.

Research Objectives of Collaborative Approach to Enterprise Modelling Traditional methods of information system analysis are based on the idea of dividing the technical system

representations into three major parts that are known as data architecture, application architecture and technology architecture. Although there is a great power in separation of different technical architectures, there is also a deep fallacy in such orientation. The major problem is that the implementation dependent level of abstraction is not taking into account some important interdependencies that are crucial to glue the static and dynamic aspects of enterprise architecture. Such system development tradition tends to draw attention away from the strategic and business process modelling aspects. For instance, the object-oriented models do not take care of interdependencies of various diagrams as well as the communication dependencies among organisational and technical system components. If the organisational system infrastructure and enterprise re-engineering strategy is not considered in building the information technology infrastructure, then it may result in wasting huge amounts of resources.

Various studies of enterprise engineering problems in different companies and in the public sector have demonstrated that an integrated representation of the organisational and technical system structure is necessary to understand orderly transitional processes from the current to the target enterprise architecture. The organisational and technical requirements need to be captured, visualised and agreed upon (Gustiene & Gustas, 2002). Just as the complex buildings or machines require explicit representations of their design structures, so does an overall enterprise infrastructure. The integrated enterprise modelling foundation (Gustas, 2000) is necessary to facilitate reasoning and understanding of enterprise architectures across organisational and technical system boundaries (Gustas & Gustiene, 2003). Various static and dynamic dependencies that define enterprise engineering products can not be analysed in isolation, they should be shared in collaborative enterprise modelling along the planner, owner, designer, builder and subcontractor perspectives (CIO council, 1999). In this project, we are going to define a core set of dependencies that should serve as building blocks of the essential architectural patterns on various levels of abstraction. The core dependencies should be propagated and rooted in the basic building constructs of the traditional approaches that define system development solutions in different perspectives and across various views. We will concentrate our research around the following development layers and views:

�� The strategy-oriented business process development layer (planner view), �� The business process modelling and integration layer (owner view), �� The technical system development layer (designer and builder views).


We are going to consider a twofold nature of collaborative enterprise engineering: among different types

of participants, i.e. across perspectives and views, and among the same type of experts, i.e. within one perspective and across different views, but on various levels of abstraction. The strategy – oriented enterprise engineering is dealing with development of the target architecture and consists of a vision, principles, goals and objectives (CIO council, 1999). Since this activity concentrates on the strategic description and transitional processes, we will sometimes refer to it as the pragmatic layer of enterprise engineering. The target architecture consists of two parts: business process architecture and technical system architecture. The business process architecture is implementation independent and it is supposed to prescribe the technical system architecture. We will refer to business process re-engineering activity as enterprise engineering at the semantic layer. The technical system modelling would correspond to enterprise engineering at the syntactic layer.

The pragmatic layer concentrates on a strategic description (Yu & Mylopoulos, 1994), i.e. it is supposed to give a definition of the "why" - a long-term intention or a vision of the enterprise under development. A pragmatic description of enterprise components motivates the semantic descriptions (Gustas et al., 1996) on various levels of abstraction. Sometimes, desired technical components can be easily described before the goals are well understood. Elaboration of the objectives is then done backwards, by asking for the reason for existence of the introduced components. Information system methodologies recognise that it is not enough to concentrate distinctly on the syntactic layer, without taking into account the semantics and pragmatics. Since various types of dependencies cannot be analysed in isolation, one of the main theoretical objectives of this project is to identify and to define interplay among various types of enterprise modelling dependencies (Gustas, 1997) that describe different layers, perspectives and views.

The enterprise engineering quality (Gustiene, 2003) is essential for understanding of the organisational and technical system fitness. Nevertheless, it is very little known on how the enterprise modelling quality problems are identified. Various diagrammatic constructions that humans employ for representation of enterprise architectures on different levels of abstraction should be evaluated by certain quality criteria. The quality criteria are still poorly understood in the area of information systems. Lindland, Sindre and Solvberg (Lindland et al., 1994) have proposed a framework for understanding the syntactic, semantic and pragmatic quality. The syntactic quality can be characterised by correctness of modelling language. Two characteristic features of the semantic quality are validity and completeness. Validity means that all statements in the model are relevant to the problem. Completeness means that the enterprise model contains all relevant statements. It is not easy to apply these two criteria in practice, because we do not know how the semantic quality can be measured. A better pragmatic quality of system specification would mean that all concerned participants understand how the intended system is going to function and all stakeholders agree on what is going to be achieved. Misunderstanding and disagreement among them in terms of the semantic differences in diagrams would automatically imply a lower pragmatic quality of enterprise architecture.

The semantic quality is essential when the enterprise engineering product is intended to serve for effective communication of various architectural solutions among system designers and system users. A new enterprise modelling method should be used for visualisation and reasoning about integrity of enterprise architectures. Integrated way of dealing with the graphical dependencies at various levels of abstraction might help us to use enterprise models for identification of such undesirable qualities as inconsistency, incompleteness (underspecification, overspecification), incoherence and ambiguity of business process models. Communication action based paradigm to enterprise modelling (Gustas, 1997), (Gustas, 1998), (Gustas & Gustiene, 2002), (Gustas & Gustiene, 2003) has been proved to be useful for identification of the semantic quality problems. Consistent way of dealing with the graphical dependencies on various levels of abstraction might help us to better understand quality problems during enterprise modelling and integration. A new graphical enterprise engineering method should open a totally new way for collaborative enterprise engineering in the area of electronic commerce.

Various processes of services should be defined and analysed with respect to the business objectives. Although some progress has been made in the area of web service design as far as new technical standards are concerned (Petit, 2003), there is still a long way to go. The semantic issues need to be addressed and fundamental research must be performed in connection to the integrated enterprise modelling foundation and engineering principles. Our expectation is that the new enterprise modelling foundation might help us to find solutions for the following difficult problems:

1) Ambiguity problem. Systems are spanning across organisational and technical system boundaries. These boundaries are changing over time and not always clear. That is why sometimes requirement


specifications are ambiguous. We are going to use the strategic and actor communication dependencies in a core of our approach, because they are crucial for identification of boundary shift and architectural changes.

2) Integration problem. Various models are used for representation of static and behavioural aspects of enterprise architecture. A clear way of integration between these models is missing. A service based actor communication approach will help us to glue the static and dynamic aspects enterprise architecture. Enterprise models will provide a comprehensible foundation to understand the interplay between various pragmatic and semantic dependencies.

3) Consistency problem. The same enterprise architecture can be perceived by different actors in a number of ways and therefore it can be represented on the various levels of abstraction. Consistent way of dealing with the strategic, business process and implementation dependent representations of requirements is missing in most information system methodologies. A new enterprise modelling method will help us to identify contradictory statements across different views.

4) Completeness problem. There are no stopping rules for a process of enterprise modelling. Properly defined foundations of enterprise architecture on the pragmatic, semantic and syntactic layers might suggest a new way of dealing with over specification and under specification in various perspectives.

5) Change problem. Every new solution can be considered to be a symptom for a new problem. Any change that is caused by an individual actor view or perspective should be managed in a systematic way by using different versions of the enterprise architecture. A new enterprise modelling approach will prescribe cooperative principles of fragment control. Influences from one actor view to another should be possible to trace, because of well defined strategic and communication interdependencies. Therefore, an overall enterprise architecture change management problems can be tackled in a collaborative and systematic way.

Potential impact One of the most difficult problems in the area of electronic business development is a communication gap

between system designers and users. System designers use a computer jargon that is alien to the users. Similarly, the terminology used by stakeholders may be difficult to understand for the development staff of computerised information system. A key problem is determining the true needs and how these needs can be integrated into the unambiguos, complete and consistent description of enterprise architecture. Managers would like to have flexible methods for capturing their business knowledge and converting it into the specifications of computerised system. There is also a need for reliable methods that assist assesment of business possibilities for electronic commerce. Today we experience a major paradigm shift in the way organisational and software system architectures are designed. Service oriented system engineering is a new emerging approach for e-business development that has evolved from the object-oriented and component-based system engineering. Services can be represented as autonomous descriptions that are defined and published using XML artefacts (www.xml.com).

Graphical descriptions of services are subject for search, change, analysis and integration across technical and organisational boundaries. Service representations should include not just software components, but definition of interoperation details among various actors of business processes. A self-describing nature of services on the Internet and particularly the ability to define requirements for business collaborations would provide significant competitive advantages. Recent developments in the area of workflow management systems, semantic web and knowledge engineering give us indication that service modelling can provide the automated support needed for e-business integration both at the data and the business process level. Adopting the service oriented paradigm as a glue for enterprise modelling and integration has the potential to reduce web-based system development complexity and costs, to lower maintenance costs, to increase e-business re-engineering efficiency and to identify new revenue streams.

However, before the collaborative enterprise engineering becomes reality, there are a number of challenging problems that need to be solved. The most important fundamental issues include service and service deployment architecture modelling, service composition, evolution, integration and engineering of supporting technologies and infrastructure. Most of the current World Wide Web (WWW) content about services is designed for humans to navigate hypertext links. Surely computers can parse web pages, but they have no reliable way to process the semantics of information on the Web (Berners-Lee et al., 2001). Many researchers believe in a possibility of the WWW extension, which is referred to as the Semantic Web (see www.w3.org). It is supposed to carry out sophisticated tasks for users by meaningfully manipulating information that is presented on various websites. Weaving of the semantic information into well defined

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meaning would enable human and computer to better ‘understand’ each other, not merely enter, store and display what is represented in each separate information warehouse.

The challenge of Semantic Web is to provide a language that expresses semantics of concepts and allows to introduce reasoning rules about services. It seems like the important techniques for developing of the semantic web are already established: XML and resource description framework (RDF). XML allows to define own tags that create the structure for text presented on web pages. XML gives possibility for users to classify words in the documents, but it says nothing about the meaning of concepts. RDF schema can be used for the expression of meaning. It asserts various concepts such as properties (attributes) of resources (subjects) with certain values (objects). Resources and values can be identified with a Universal Resource Identifier (URI) in the same way as links are defined between web pages. Nevertheless, the same words about services in various places may have a different meaning, as well as different words may have the same meaning. Programs that are supposed to process the semantic information must have a way to discover commonalities and differences of concepts across different services on the Internet. A solution to this problem could be provided by the semantic and pragmatic structures of distributed enterprise models that sometimes are called ontology.

The term of ontology is used in many different senses. In philosophy, ontology is a theory underlying the nature and existence of various types of objects. Many semantic web researchers would use the notion of ontology to call a document that formally defines the relations among various terms. The most typical ontology for the semantic web has a concept taxonomy structure and a set of inference rules. In the area of artificial intelligence, ontology is defined as a specification of a conceptualisation. Service ontology should define its actors, concepts, actions and business relationships. Thus, foundations of service ontology should analyse how the general similarities and differences of abstract concepts can be defined. It must be able to address fundamental semantic issues on how service structures are built and processed. Although some promising models and methods in the area of enterprise and information system engineering exist, unfortunately, comprehensive fundamentals of ontology processing are not developed yet.

Many internet agents already exist, but none of them has a capacity to locate another one that is necessary to perform a specific service. This functionality is not possible to implement, because the agency on the Semantic Web is not enforcing any universal semantic structure, which can be used for service discovery and re-engineering. Therefore, ontology should not just express the static semantic structures to be used for the further enhancement of reasoning, but it should also be able to define the dynamic structure of available services. RDF language can describe properties of any equipment such as cell phones, software components or computers. Since an URI can point out to any organisation, software component or hardware device, such syntactic service identification capability on the web should help enterprise engineers to cross boundary between conceptual representations of services and physical reality.

The main barrier in designing new electronic businesses on the Internet lies in difficulty to define and agree on the standards of interoperation. Therefore, the ontological representations of services should be complemented by a capacity to define the agent interoperation dependencies. The consumer and producer agents can reach mutual ‘understanding’ by exchanging their own enterprise representations that include semantic descriptions of products and services. Due to variety of electronic commerce systems and components deployed, a common enterprise (service and product) engineering language should have a sharing and reasoning capability on how organisational and technical system components are used. The problem is especially acute when a large number of trading partners attempt to take advantage of services that only partially match their needs.

A typical collaborative enterprise engineering attempt should take into account value chains of the existing organisations and to facilitate reasoning on how new requested products or services are constructed on demand. Therefore, development of the semantic foundation for enterprise or web service engineering is not sufficient. Additionally, to sustain and to support development of agent formations, organisational and technical components have to share the pragmatic knowledge: information about problems, opportunities and intensions of agents. If the integrated semantic and pragmatic representations are properly maintained on the web, it can assist evolution of knowledge for wider communities. It should be noted that coordinating actions across wider groups of individuals is painfully slow, because it involves a lot of communication. Nevertheless, quite often the process of bridging similar concepts in different groups of people brings great benefits.


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