1. Enterprise Architecture (Unit 6)
Lecture 10
Enterprise Architecture
(Unit 6)
We come across the two terms IS infrastructure and architecture. IS Infrastructure consists of the physical facilities, services, and management that support all shared resources in an organisation. Turban describes this on page 65. neither Turban nor laudon deals with enterprise architecture.

2. Reference
Information Systems management in Practice by Barbara C McNurlin and Ralph H. Sprague Jr, Prentice Hall
Refer to OASIS for additional reading

3. What is an Enterprise?
“.. any collection of organizations that has a common set of goals/principles and/or single bottom line. In that sense, an enterprise can be a whole corporation, a division of a corporation, a government organization, a single department, or a network of geographically distant organizations linked together by common objectives.”
(Institute for Enterprise Architecture Developments)
For example, take a social enterprise. These are businesses that trade in order to fulfil social aims of and objectives. For a sport social enterprise these aims could be: to encourage people who usually do not engage in sports or exercise into doing physical activities, to provide access to sport facilities to low income people, or to provide coaching qualifications to unemployed, etc.

4. Go to the ‘Frequently Asked Questions’ on the Open Group website at: and read the section under the heading, ‘What is an enterprise?

5. What is system architecture ?
A framework is a set of assumptions, concepts, values, and practices that constitutes a way of viewing reality
What is a framework ?
‘the art or practice of designing and building structures’, or ‘a method or style of building’.
What is Architecture ?
the result of a design process for a specific system that specifies the functions of components, their interfaces, their interactions, and constraints.
A framework is a set of assumptions, concepts, values, and practices that constitutes a way of viewing reality (O’Rouke et al.). The Webster’s dictionary defines architecture as, ‘the art or practice of designing and building structures’, or ‘a method or style of building’. System architecture refers to the architecture of a specific construction or system. It is the result of a design process for a specific system that specifies the functions of components, their interfaces, their interactions, and constraints. This specification is the basis for detailed design and implementation steps.
What is system architecture ?

6. Builder’s Implementation
Building
Architect’s Plan
Builder’s Implementation
Owner’s view
Concrete
abstract
Owner has a strategy as to how to live in a house. The architect develops a plan based on this vision. The plan provides a guide to the builders, carpenters, electricians, etc who actually builds the house. Guided by their past experience, industry standards, etc. they will select the best material, construction techniques best suited to the plan. The plan also guides them as to what to put where. The end product should fulfil the owner’s vision. The owner may add the finishing touches such as light fixtures, curtains, and furniture completing the infrastructure. Infrastructure in an organisation is similar to the wiring, plumbing and furnishings in a house.
Similarly an IT architecture provides a blueprint to convert the business strategy into a plan for IS. An IT infrastructure includes everything that supports the flow and processing of information in an organisation, including hardware, software, networks and communications, and data. It consists of components chosen and assembled in a manner that best suits the plan and therefore best enables the business strategy.
Strategy
Architecture
Infrastructure
Information Technology
Pearlson and Saunders, page 129

7. Architecture is…
‘.. That set of descriptive representations, that are relevant for describing an object such that it can be produced and maintained over the period of its useful life.’ Zachman

8. Applying to an Enterprise:
‘.. That set of descriptive representations (i.e. models), that are relevant for describing an Enterprise such that it can be produced to management’s requirements (quality) and maintained over the period of its useful life (change).’ Zachman

9. Simply put…
Enterprise architecture is a means to organise, communicate, and manage IT and business operations.
(O’Rouke et al., 2003)

10. Information Systems Architecture is…
The basic blue print showing how a firm’s data processing systems, telecommunication networks, and data are integrated

11. Objectives of an architecture:
Abstracts the description of complex dynamic systems by providing simple models
helps the designer in defining and controlling the interfaces and the integration of the system components
Based on the previous definitions we can say that an architecture serves the following purposes

12. Objectives of an architecture:
Reduce the impact of changes
architectural model of a system allows to focus on the areas requiring major changes
Indicates the most vital components of the system that should not be violated during modifications and enhancements
Is a means of communication during the design or re-design process
During a redesign process, the architecture enables to reduce the impact of changes to as few modules as possible. The architectural model of a system allows to focus on the areas requiring major changes.
The architecture indicates the most vital components and constructs of the system that should not be violated when adapting the system to new uses. Violating the architecture is similar to removing load-bearing walls in a house, decreasing the system’s ability to change gracefully with changing requirements and constraints.
The architecture is a means of communication during the design or re-design process. It may provide several abstract views on the system which serve as a discussion basis to clarify each party’s perception of the problem area.

13. Bernard (2004) defines EA as ‘both a management program and a documentation method that together provides an actionable, coordinated view of an enterprise’s strategic direction, business processes, information flows, and resource utilization’.

14. As a Management program:
Provides a strategic integrated approach to resource planning.
Can help to identify gaps in the performance
Support the implementation of standardised management policy

15. Value:
For large, distributed global enterprises, can be an effective governance process for IT resources
For smaller, more centralised enterprises, can help to ensure the organisation remains able to align business requirements with technology solutions

16. Value: Improved Planning – Decision making Communication Managing Risk
both top-down and bottom up
Supports program and project management by providing a baseline of reference documents
Decision making
Communication
Managing Risk

17. Developing an EA
The process addresses documenting and understanding the components within the categories:
Business
Applications
Information
Technology

18. Visit ‘Enterprise Architecture Tools’ at Institute for Enterprise Architecture Developments at:
It is important to note that there is not ONE single architecture, but a set of architectural representations that can be produced representing different views of an enterprise. Each representation has a different nature or perspective. The level of detail held in each representation serves a different purpose.

19. Example

21. EA Frameworks
Provide a method of organising, or techniques for the modelling of current views, future scenarios, and establish a repository

22. Go to the ‘Frequently Asked Questions’ on the Open Group website at: and read the section under the heading, ‘Why do I need a framework for enterprise architecture?’.

23. EA Frameworks Zachman Frame work
DODAF –
MODAF -
TOGAF -

24. Zachman’s Framework
Introduces a framework for constructing an architecture for IS
First introduced in 1987 –
3 columns (data, process, network) and 5 rows
1992 – introduced 3 more columns
People, time, and purpose
6 x 6 matrix
It was first published in 1987 in the IBM Systems journal. First he created a descriptive framework from disciplines quite independent of IS. Based on this neutral objective framework he introduced IS architecture. The initial Zachman’s framework consisted of 3 columns (data, process and network) and 5 rows making a 15 grid structure. He also proposed 3 more possible columns. Then in 1992 these 3 columns, people, time, and purpose were described in detail in another publication. Today it stands as 36 cell matrix.

25. Zachman’s Framework Three perspectives from different roles played:
Customer, the ultimate Owner
Engineer or Designer
Builder or product engineer

26. J. A. Zachman, (1999), Systems Architecture, IBM Systems Journal, Volume 38, Numbers 2 & 3, 1999, pp

27. Zachman’s generic logic structure
Buildings
Airplanes
Ballpark View (scope)
Bubble chart
Concepts
Architect’s drawing
Work breakdown structure
owner
Perspectives
Architect’s plans
Engineering design
designer
Constructor’s plans
Manufacturing/ Engineering design
builder
Assembly/fabrication drawings
Sub-contractor
Shop plans
Machine language representation
Numerical code programs
product
Building
Airplane

28. Aspects Perspectives Data (what) Function (how) Network (where)
People (who)
Time (when)
Motivation (why)
Planner (scope)
owner
Perspectives
designer
builder
Sub-contractor
Functioning enterprise

29. Zachman’s Framework WHAT the product is made of (material)
HOW the product works (function)
WHERE the components are located relative to one another (geometry)
WHO does what relative to the product
WHEN do things happen
WHY are various product choices being made

30. The Zachman Institute for Framework Advancement http://www.zifa.com
Enterprise Information Architecture
The Zachman Institute for Framework Advancement

31. Zachman’s Framework
"To keep the business from disintegrating, the concept of information systems architecture is becoming less of an option and more of a necessity."
John Zachman, 1987

32. TOGAF by the Open Group
Originated as TAFIM (Technical Architecture for Information Management) in the US Department of Defence
adopted by the Open Group in the mid-1990s.
The first TOGAF specification was introduced in 1995
The current version is 8.1.1
A common point of perception is that TOGAF is not actually an architecture, but rather a framework for designing and describing an architecture.

33. an open framework freely disseminated by the Open Group
available on the Open Group website
TOGAF specification and all related documentation are freely available on the Open Group website ( and organisations embarking on enterprise architecture are encouraged to use it

34. GM’S Cure for Complexity by Richard Pastore, CIO Magazine, Sep
GM’S Cure for Complexity by Richard Pastore, CIO Magazine, Sep. 1, an interview with GM’s CTO, Tony Scott