nach oben

2013 | Buch | 3. Auflage

Kapitel lesen Erstes Kapitel lesen

Enterprise Architecture at Work

Modelling, Communication and Analysis

verfasst von: Marc Lankhorst

Verlag: Springer Berlin Heidelberg

Enthalten in: Springer Professional "Wirtschaft+Technik" , Springer Professional "Technik" , Springer Professional "Wirtschaft"

Einloggen, um Zugang zu erhalten

Über dieses Buch

An enterprise architecture tries to describe and control an organisation’s structure, processes, applications, systems and techniques in an integrated way. The unambiguous specification and description of components and their relationships in such an architecture requires a coherent architecture modelling language.

Lankhorst and his co‑authors present such an enterprise modelling language that captures the complexity of architectural domains and their relations and allows the construction of integrated enterprise architecture models. They provide architects with concrete instruments that improve their architectural practice. As this is not enough, they additionally present techniques and heuristics for communicating with all relevant stakeholders about these architectures. Since an architecture model is useful not only for providing insight into the current or future situation but can also be used to evaluate the transition from ‘as‑is’ to ‘to‑be’, the authors also describe analysis methods for assessing both the qualitative impact of changes to an architecture and the quantitative aspects of architectures, such as performance and cost issues.

The modelling language presented has been proven in practice in many real‑life case studies and has been adopted by The Open Group as an international standard. So this book is an ideal companion for enterprise IT or business architects in industry as well as for computer or management science students studying the field of enterprise architecture.

Inhaltsverzeichnis

Frontmatter

Chapter 1. Introduction to Enterprise Architecture

Abstract

In current business practice, an integrated approach to business and IT is indispensable. As a real-life example, take the Dutch government, who are currently undertaking a massive redesign of the entire chain of organisations involved in the social security system. Within this context, the collection of employees’ social security premiums is transferred from the central social security organisation to the tax administration. This sounds logical, since collecting taxes is superficially very similar to collecting social security premiums. However, this seemingly simple change entails a major redesign of organisational structures, business processes, IT applications, and technical infrastructure. Enormous flows of data need to be redirected within and among the different organisations: more than 600,000 payroll tax returns are filed each month, a large proportion of which arrive within a peak period of a couple of days.

Marc Lankhorst

Chapter 2. State of the Art

Abstract

This chapter gives an overview of currently used methods and techniques in enterprise architecture. Naturally, this description is a snapshot, and we cannot claim to be exhaustive, since the field of enterprise architecture is evolving rapidly. However, it provides this broad overview of current methods and techniques to give the reader an impression of the advances in this field.

Marc Lankhorst

Chapter 3. Foundations

Abstract

This chapter lays down the fundamental ideas and choices on which our approach is based. First, it identifies the needs of architects in the design, communication, realisation, and change of enterprise architectures. It then describes the central role of architecture models in our approach, the use of models in communication, the relationship between models and their presentation, and the formalisation of the meaning (i.e., semantics) of models.

Marc Lankhorst

Chapter 4. Communication of Enterprise Architectures

Abstract

This chapter presents a communication perspective of enterprise architectures. We provide both a theoretical and a practical perspective of the issues involved in the communication of enterprise architectures. The general idea is that the chapter helps the reader see how architecture development and modelling can be optimally supported by discussing why certain forms of modelling are used in some situation and how this fits the goals in the process. The theoretical perspective will focus on communication during system development in general, where the word system should be interpreted as any open and active system, consisting of both human and computerised actors, that is purposely designed. The practical perspective will take shape as a set of practical guidelines that should aid architects in the selection and definition of architecture description approaches that are apt for a specific (communication) context.

Marc Lankhorst

Chapter 5. A Language for Enterprise Modelling

Abstract

Architecture provides a means to handle the complexity of modern information-intensive enterprises. To this end, architects need ways to express architectures as clearly as possible: both for their own understanding and for communication with other stakeholders, such as system developers, end users, and managers. Unfortunately, the current situation is that architects in different domains, even within the same organisation, often use their own description techniques and conventions. To date, there is no standard language for describing enterprise architectures in a precise way across domain borders. They are often described either in informal pictures that lack a well-defined meaning, or in detailed design languages (such as UML) that are difficult to understand for non-experts. This frequently leads to misunderstandings that hinder the collaboration of architects and other stakeholders. Also, it makes it very difficult to provide tools for visualisation and analysis of these architectures.

Marc Lankhorst

Chapter 6. Guidelines for Modelling

Abstract

This chapter will help you create good enterprise architecture models. To do so, we discuss the act of modelling as a goal-driven activity, the role of the stakeholders, as well as the modelling process in general. The chapter focuses on the key aspects of modelling: the use of abstraction levels, the choice of modelling concepts and relations, and different ways of structuring and visualising models. The results are presented in the form of guidelines for modelling and visualisation.

Marc Lankhorst

Chapter 7. Viewpoints and Visualisation

Abstract

Establishing and maintaining a coherent enterprise architecture is clearly a complex task, because it involves many different people with differing backgrounds using various notations. In order to get to grips with this complexity, researchers have initially focused on the definition of architectural frameworks for classifying and positioning the various architecture descriptions with respect to each other. A problem with looking at enterprise architecture through the lens of an architectural framework is that it categorises and divides architecture descriptions rather than providing insight into their coherence.

Marc Lankhorst

Chapter 8. Architecture Analysis

Abstract

As we have argued in previous chapters, organisational effectiveness cannot be achieved through local optimisations, but is realised by well-orchestrated interaction of organisational components (Nadler et al. 1992). To create such an integrated perspective of enterprise architecture, we need both a description technique for architectural models and model-based analysis techniques to realise this global optimisation in practice.

Marc Lankhorst

Chapter 9. Architecture Alignment

Abstract

As we have described in Chap. 1, achieving alignment between business and IT is one of the most important drivers for architecture. Architecture alignment is the problem of designing architectures at the infrastructure, application, and business levels such that each fits optimally with the other architectures. By studying project documentation obtained in case studies in several large Dutch organisations, we have tried to find alignment patterns that are actually used in practice. These results provide the context in which architectures are designed. Insight into this context helps the reader in better applying the techniques presented in this book.

Marc Lankhorst

Chapter 10. Tool Support

Abstract

Enterprise architecture, by nature, requires the interconnection and accumulation of large amounts of information from various sources. An enterprise modelling language, such as the one introduced in Chap. 5, can only be successful if supported by adequate tooling. Visualisation and analysis of architectures, as described in Chaps. 7 and 8, respectively, can hardly be carried out by hand and require tools as well. In this chapter, we outline the current state of the art in enterprise architecture tools, outline our vision of future tool support, and describe the design and operation of a number of (prototype) tools that support the modelling language, visualisation, and analysis techniques described in previous chapters. Specifically, we will focus on the design of a general enterprise architecture workbench, the necessary infrastructure for viewpoint-based architecture modelling, and tools for functional and quantitative analysis of architectures. The next chapter, on practical applications, will describe the use of some of these tools in practice.

Marc Lankhorst

Chapter 11. Case Studies

Abstract

To obtain input from practice and to validate the concepts and techniques explained in the previous chapters, several partner-specific case studies have been executed. These have also served as an important means for knowledge transfer from research to practice. This chapter will elaborate on three of these case studies.

Marc Lankhorst

Chapter 12. Beyond Enterprise Architecture

Abstract

In the previous chapters we have discussed enterprise architecture modelling and analysis, its roots and foundations, and have seen enterprise architecture being applied in a number of industrial cases. The practice and possible added value have clearly been put forward.

Marc Lankhorst

Backmatter

Titel: Enterprise Architecture at Work
verfasst von: Marc Lankhorst
Verlag: Springer Berlin Heidelberg
Electronic ISBN: 978-3-642-29651-2
Print ISBN: 978-3-642-29650-5
DOI: https://doi.org/10.1007/978-3-642-29651-2