Greefhorst / Proper Architecture Principles

The Cornerstones of Enterprise Architecture
1. Auflage 2011
ISBN: 978-3-642-20279-7
Verlag: Springer
Format: PDF
Kopierschutz: 1 - PDF Watermark

E-Book, Englisch, 197 Seiten

Reihe: Business and Management (R0)

Enterprises, from small to large, evolve continuously. As a result, their structures are transformed and extended continuously. Without some means of control, such changes are bound to lead to an overly complex, uncoordinated and heterogeneous environment that is hard to manage and hard to adapt to future changes. Enterprise architecture principles provide a means to direct transformations of enterprises. As a consequence, architecture principles should be seen as the cornerstones of any architecture.In this book, Greefhorst and Proper focus on the role of architecture principles. They provide both a theoretical and a practical perspective on architecture principles. The theoretical perspective involves a brief survey of the general concept of principle as well as an analysis of different flavors of principles. Architecture principles are regarded as a specific class of normative principles that direct the design of an enterprise, from the definition of its business to its supporting IT. The practical perspective on architecture principles is concerned with an approach to the formulation of architecture principles, as well as their actual use in organizations. To illustrate their use in practice, several real-life cases are discussed, an application of architecture principles in TOGAF is included, and a catalogue of example architecture principles is provided.With this broad coverage, the authors target students and researchers specializing in enterprise architecture or business information systems, as well as practitioners who want to understand the foundations underlying their practical daily work.

Danny Greefhorst is a principal consultant and owner of ArchiXL, and works for clients in the financial and public sector. Danny acts as an IT architect and IT consultant, and is TOGAF 9 certified. He has extensive experience with the definition and implementation of enterprise architectures, application architectures and technical architectures. In addition, he coaches organizations in setting up and executing their architecture function, and is active as an instructor for several classes on architecture. Before starting ArchiXL he worked as a principal consultant at Yellowtail, as a senior IT architect at IBM Business Consulting Services and as a researcher at the Software Engineering Research Centre. Danny is active in the architecture community and regularly publishes on IT and architecture related topics. He is the chairman of the governing board of Via Nova Architectura, a portal and electronic magazine on enterprise architecture. He is also a member of the governing board of the architecture department of the Dutch Computer Science Association (Ngi).Erik (H.A.) Proper is a senior research manager at the Public Research Centre -- Henri Tudor in Luxembourg, where he leads Services-oriented Enterprise Engineering programme. He also holds a chair in Information Systems at the Radboud University Nijmegen in the Netherlands. Erik has a mixed industrial and academic background. In the past, Erik worked for companies such as Asymetrix, InfoModeller, Origin, ID Research, Ordina and Capgemini, while interleaving this with his work at research institutions such as the Radboud University of Nijmegen, Queensland University of Technology, the Distributed Systems Technology Centre, and the University of Queensland. His general research drive is the modeling of systems. He applies this drive mainly in the fields of service science, enterprise modeling, enterprise engineering and enterprise architecting. He was co-initiator of the ArchiMate project, and currently also serves on the board of the ArchiMate forum of The Open Group. Erik is also one of the editors in chief of Springer's series on enterprise engineering.

Autoren/Hrsg.

Greefhorst, Danny

Proper, Erik

Inhaltsverzeichnis

1;Foreword;5
2;Preface;7
3;Acknowledgements;8
4;Contents;9
5;Chapter 1: Introduction;14
5.1;1.1 Challenges to Enterprises;14
5.2;1.2 Enterprise Architecture and Architecture Principles;16
5.3;1.3 Motivations and Target Audience;17
5.4;1.4 Outline of the Book;18
6;Chapter 2: The Role of Enterprise Architecture;20
6.1;2.1 Introduction;20
6.2;2.2 Enterprise Transformations and Enterprise Engineering;22
6.3;2.3 Streams of Activities in Enterprise Engineering;24
6.4;2.4 Architecture-Based Governance of Enterprise Transformations;27
6.4.1;2.4.1 The Need for Architecture;27
6.4.2;2.4.2 Architecture as a Bridge from Strategy to Design;29
6.4.3;2.4.3 Steering with Architecture;31
6.4.4;2.4.4 The Three Roles of Enterprise Architecture;32
6.5;2.5 Defining Enterprise Architecture;33
6.5.1;2.5.1 The Purpose of an Enterprise Architecture;34
6.5.2;2.5.2 The Meaning of an Enterprise Architecture;35
6.5.3;2.5.3 The Elements of an Enterprise Architecture;35
6.5.4;2.5.4 Definition of Enterprise Architecture;37
6.6;2.6 Other Forms of Architecture;37
6.7;2.7 Standards for Enterprise Architecture;39
6.8;2.8 The Role of Architecture Principles;41
6.9;2.9 Key Messages;42
7;Chapter 3: A Conceptual Framework for Principles;43
7.1;3.1 Introduction;43
7.2;3.2 Background of Architecture Principles;44
7.3;3.3 Key Classes of Principles;46
7.3.1;3.3.1 Scientific Principles;46
7.3.2;3.3.2 Design Principles as Normative Principles;47
7.3.3;3.3.3 From Credos to Norms;50
7.3.4;3.3.4 Conceptual Framework;52
7.4;3.4 Architecture Principles as Pillars from Strategy to Design;56
7.4.1;3.4.1 Architecture Principles;56
7.4.2;3.4.2 Business and IT Principles;56
7.4.3;3.4.3 Bridging from Strategy to Design;58
7.4.4;3.4.4 Extended Conceptual Framework;60
7.5;3.5 Motivating Architecture Principles;61
7.5.1;3.5.1 Sources for Finding Motivation;62
7.5.2;3.5.2 Drivers as Motivation for Architecture Principles;64
7.5.3;3.5.3 Extended Conceptual Framework;66
7.6;3.6 Formal Specification of Normative Principles;68
7.7;3.7 Key Messages;70
8;Chapter 4: Architecture Principle Specifications;71
8.1;4.1 Introduction;71
8.2;4.2 Dimensions in Architecture Principles;74
8.2.1;4.2.1 Type of Information Dimension;75
8.2.2;4.2.2 Scope Dimension;75
8.2.3;4.2.3 Genericity Dimension;76
8.2.4;4.2.4 Level of Detail Dimension(s);77
8.2.5;4.2.5 Stakeholder Dimension;78
8.2.6;4.2.6 Transformation Dimension;78
8.2.7;4.2.7 Quality Attribute Dimension;79
8.2.8;4.2.8 Meta-level Dimension;81
8.2.9;4.2.9 Representation Dimension;81
8.3;4.3 Attributes;82
8.3.1;4.3.1 Basic Structure;83
8.3.2;4.3.2 Advised Attributes;85
8.3.3;4.3.3 Attributes for Classification;87
8.3.4;4.3.4 Potential Attributes;87
8.3.5;4.3.5 Generic Meta-data Attributes;88
8.3.6;4.3.6 Relationships;89
8.4;4.4 Architecture Principle Sets;91
8.5;4.5 Quality Criteria;93
8.6;4.6 Key Messages;95
9;Chapter 5: A Practical Approach;96
9.1;5.1 Introduction;96
9.2;5.2 Generic Process;99
9.2.1;5.2.1 Determine Drivers;99
9.2.1.1;5.2.1.1 Example: Determining Drivers for EnsureIt;101
9.2.2;5.2.2 Determine Principles;102
9.2.2.1;5.2.2.1 Generate Candidate Principles;102
9.2.2.2;5.2.2.2 Select Relevant Principles;104
9.2.2.3;5.2.2.3 Formulate Principle Statements;107
9.2.2.4;5.2.2.4 Example: Determining Architecture Principles for EnsureIt;107
9.2.3;5.2.3 Specify Principles;109
9.2.3.1;5.2.3.1 Example: Specifying Architecture Principles for EnsureIt;110
9.2.4;5.2.4 Classify Principles;111
9.2.4.1;5.2.4.1 Example: Classifying Architecture Principles for EnsureIt;111
9.2.5;5.2.5 Validate and Accept Principles;111
9.2.5.1;5.2.5.1 Example: Validating Principles for EnsureIt;112
9.2.6;5.2.6 Apply Principles;112
9.2.6.1;5.2.6.1 Transformation;113
9.2.6.2;5.2.6.2 Example: Transforming an Architecture Principle for EnsureIt;114
9.2.6.3;5.2.6.3 Architectural Knowledge Management;115
9.2.7;5.2.7 Manage Compliance;116
9.2.7.1;5.2.7.1 Example: Reviewing Principles for EnsureIt;118
9.2.8;5.2.8 Handle Changes;119
9.2.8.1;5.2.8.1 Example: Handling Changes for EnsureIt;120
9.3;5.3 Key Messages;120
10;Chapter 6: Case Studies;121
10.1;6.1 Introduction;121
10.2;6.2 ICTU;122
10.2.1;6.2.1 Introduction;122
10.2.2;6.2.2 Architecture Principles;123
10.2.3;6.2.3 Approach;125
10.3;6.3 CVZ;125
10.3.1;6.3.1 Introduction;125
10.3.2;6.3.2 Architecture Principles;127
10.3.3;6.3.3 Approach;128
10.4;6.4 Enexis;130
10.4.1;6.4.1 Introduction;130
10.4.2;6.4.2 Architecture Principles;131
10.4.3;6.4.3 Approach;131
10.5;6.5 TKP Pensioen;134
10.5.1;6.5.1 Introduction;134
10.5.2;6.5.2 Architecture Principles;135
10.5.3;6.5.3 Approach;137
10.6;6.6 Schiphol;137
10.6.1;6.6.1 Introduction;138
10.6.2;6.6.2 Architecture Principles;139
10.6.2.1;6.6.2.1 Principle: Reuse Before Buy Before Build;139
10.6.2.2;6.6.2.2 Principle: Adhere to the Corporate Data Model;140
10.6.3;6.6.3 Approach;140
10.7;6.7 Key Messages;142
11;Chapter 7: Architecture Principles in Context;143
11.1;7.1 Introduction;143
11.2;7.2 Types of Architectures;144
11.2.1;7.2.1 Enterprise Architecture Development;144
11.2.2;7.2.2 Reference Architecture Development;145
11.2.3;7.2.3 Solution Architecture Development;146
11.3;7.3 Architecture Maturity;147
11.3.1;7.3.1 Department of Commerce Maturity Model;147
11.3.2;7.3.2 Architecture Maturity and Architecture Principles;149
11.4;7.4 Culture;152
11.5;7.5 Key Messages;155
12;Chapter 8: Summary, Conclusions and Future Work;156
12.1;8.1 Summary and Conclusions;156
12.2;8.2 Future Work;158
13;Appendix A Principles Catalogue;161
13.1;Abstract;161
13.2;A.1 Business Units Are Autonomous;161
13.3;A.2 Customers Have a Single Point of Contact;162
13.4;A.3 Stock Is Kept to a Minimum;162
13.5;A.4 Processes Are Straight Through;163
13.6;A.5 Processes Are Standardized;163
13.7;A.6 Management Layers Are Minimized;164
13.8;A.7 Tasks Are Designed Around Outcome;164
13.9;A.8 Routine Tasks Are Automated;164
13.10;A.9 Primary Business Processes Are not Disturbed by Implementation of Changes;165
13.11;A.10 Components Are Centralized;165
13.12;A.11 Front-Office Processes Are Separated from Back-Office Processes;166
13.13;A.12 Channel-Specific Is Separated from Channel-Independent;166
13.14;A.13 The Status of Customer Requests Is Readily Available Inside and Outside the Organization;167
13.15;A.14 Data Are Provided by the Source;167
13.16;A.15 Data Are Maintained in The Source Application;167
13.17;A.16 Data Are Captured Once;168
13.18;A.17 Data Are Consistent Through All Channels;168
13.19;A.18 Content and Presentation Are Separated;169
13.20;A.19 Data Are Stored and Exchanged Electronically;169
13.21;A.20 Data That Are Exchanged Adhere to a Canonical Data Model;170
13.22;A.21 Data Are Exchanged in Real-Time;170
13.23;A.22 Bulk Data Exchanges Rely on ETL Tools;171
13.24;A.23 Documents Are Stored in the Document Management System;171
13.25;A.24 Reporting and Analytical Applications Do Not Use the Operational Environment;172
13.26;A.25 Applications Have a Common Look-and-Feel;172
13.27;A.26 Applications Do Not Cross Business Function Boundaries;172
13.28;A.27 Applications Respect Logical Units of Work;173
13.29;A.28 Applications Are Modular;173
13.30;A.29 Application Functionality is Available Through an Enterprise Portal;174
13.31;A.30 Applications Rely on One Technology Stack;174
13.32;A.31 Application Interfaces Are Explicitly Defined;175
13.33;A.32 Proven Solutions Are Preferred;175
13.34;A.33 IT Systems Are Scaleable;176
13.35;A.34 Only in Response to Business Needs Are Changes to IT Systems Made;176
13.36;A.35 Components Have a Clear Owner;177
13.37;A.36 IT Systems Are Standardized and Reused Throughout the Organization;177
13.38;A.37 IT Systems Adhere to Open Standards;178
13.39;A.38 IT Systems Are Preferably Open Source;178
13.40;A.39 IT Systems Are Available at Any Time on Any Location;179
13.41;A.40 IT Systems Are Sustainable;179
13.42;A.41 Processes Are Supported by a Business Process Management System;179
13.43;A.42 Presentation Logic, Process Logic and Business Logic Are Separated;180
13.44;A.43 IT Systems Communicate Through Services;180
13.45;A.44 Reuse Is Preferable to Buy, Which is Preferable to Make;181
13.46;A.45 IT Systems Support 24*7 Availability;181
13.47;A.46 IT Systems Are Selected Based on a Best-of-Suite Approach;182
13.48;A.47 Sensitive Data Are Exchanged Securely;182
13.49;A.48 IT Systems May Under no Circumstances Revert to Insecure Mode;183
13.50;A.49 Management of IT Systems is Automated as Much as Possible;183
13.51;A.50 End-to-End Security Must Be Provided Using Multiple Defensive Strategies;184
13.52;A.51 Access Rights Must Be Granted at the Lowest Level Necessary for Performing the Required Operation;184
13.53;A.52 Authorizations Are Role-Based;185
13.54;A.53 The Identity Management Environment Is Leading for All Authentications and Authorizations;185
13.55;A.54 Security Is Defined Declaratively;185
13.56;A.55 Access to IT Systems Is Authenticated and Authorized;186
13.57;A.56 Integration with External IT Systems Is Localized in Dedicated IT Components;186
13.58;A.57 Application Development Is Standardized;187
13.59;A.58 All Messages Are Exchanged Through the Enterprise Service Bus;187
13.60;A.59 Rules That Are Complex or Apt to Change Are Managed in a Business Rules Engine;188
14;Appendix B Architecture Principles in TOGAF;189
14.1;Abstract;189
14.2;B.1 Architecture Principles in TOGAF;189
14.3;B.2 Architecture Principles in TOGAF ADM;190
14.4;B.3 Mapping the Generic Process to TOGAF's ADM;192
15;Glossary;194
16;References;196
17;About the Authors;204
17.1;Danny Greefhorst;204
17.2;Erik (H.A.) Proper;204