Architecture in ICT
Prof. dr. Daan Rijsenbrij
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Beyond the hype
Why a hype?
Having solved a few minor problems such as the year 2000 and the euro, the really
interesting challenges are yet to come.
1. The adoption of new technology in your business processes
2. Faster system development, necessary because of the e-business craze
3. Security of web based systems
4. Dismantling of legacy systems
5. Reduction in complexity and the reduction of the total cost of ownership
6. Continuous alignment between the business and ICT
According to the advertisements these are all things that can only be solved under
architecture.
At the same time many ICT managers have the idea that if a major project is getting out
of hand or the information supply has become too inflexible, then an architect is
required.
In short, architecture is the panacea for all your ICT problems.
This is not true of course. But behind all this architecture hype there is the very real
notion of architecture. And what is it exactly?
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What is architecture? - 1
In the building trade the term architecture is about 5000 years old; it has been in use
since the building of the first pyramids. Architecture stands for something like order and
harmony.
Prof. Blaauw used the term architecture in the development of OS 360, the old IBM
operating system from the sixties.
Chipmakers such as Intel also use the term architecture.
In the world of application software we have only been using the term architecture a
mere ten years. But what is it exactly? Is it more than just a fancy word for structure?
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What is architecture? - 2
Arc de Triomphe.
Our head office in Rue de Tilsitt, a “modest” building designed by one of Napoleon’s
architects, backs onto the Place de l’Etoile. I have therefore often wondered about the
architecture of this triumphal arch. Then I see
 some functionality in the structure,
 a method of construction and a particular choice of materials,
 a certain perception.
The Sydney Opera House.
The biggest extension in time and costs in the modern history of building construction.
But really very different!
What can we see here in the way of architecture?
The functionality of the building was considered: the acoustics were the main priority.
And of course the design was important. As you can see, the result is a fantastic
combination of form and function.
Finally, the Erasmus Bridge.
Here we have the beautiful Erasmus Bridge in Rotterdam. This bridge has a different
style and design, but has a problem with its construction. With too much crosswind it
starts to swing rather dangerously. But it remains a beautiful bridge.
This example shows that in addition to design aspects, consideration must also be
given to construction aspects. So in addition to architects you need engineers to do the
calculations. Co-operation is important here.
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Design Levels
What also catches the eye when you are looking at physical architectures is that there
are several layers of abstraction to be distinguished. This is done to maintain an
overview of the complexity, a sort of “divide and rule” principle in the architecture, and
to maintain an overview of the connections.
When you are designing a town, you lay it out at town level in order, only then, to be
able to do justice to the areas in terms of functionality and to erect buildings and allow
them to be used effectively and efficiently, so that it is clear what functions parts of a
given town have: work, living, recreation, schools, shops, etc., etc.
This zooming in on different levels also happens with ICT architecture. We might for
example talk about ICT architecture at enterprise level (enterprise architecture), ICT
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architecture in a project for several information systems and the architecture of an
individual information system.
In some places in the literature you will find that mention is only made of architecture at
enterprise level and that the rest is seen as specialisation. This is also where the
fundamental line of demarcation lies between architect and designer.
At the different levels there are different stakeholders with different interests. Once
again it is important to identify these levels explicitly in your ICT.
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Aspects of architecture
When you look at a building, there are three important aspects to consider: style,
content / structure and construction. Or, to put it another way, how you experience the
building, what you can do with it and how it is put together.
Style is just as important where information systems are concerned as it is in the
designing of buildings. This is expressed in the house on the left.
ICT Architecture is like industrial design. Whether you use “Word” or “Excel”, the keys
all intuitively have the same feeling, the same style.
Beauty, or “look and feel”, is important for a building. It often seems to be thought that
the exterior is there to be looked at and the interior to be used. Where ICT architecture
is concerned, both the exterior and the interior are attractive and good to use.
The style, the manifestation is important in use. Style is of vital importance for the way
in which the information system interacts with its users and its environment. Style is
also to do with beauty.
The house in the middle is the structure or the content house. What is the positioning of
the different functionalities in respect of one another and how are the quality
requirements incorporated? In other words, of what components does the information
system consist and how do they work with one another? The different client-server
models belong in this house.
The house on the right is the construction house. In other words, what materials are
used to build the house? In ICT these are questions such as:
 do I work with package software or with components?
 do we use Java and XML or do we do it with a 4GL?
 do we use a genetic algorithm or do we put down a neural network?
The houses are not of course completely detached from one another. Choices in one
can influence the freedom in another. But it is important to pay sufficient attention to all
three houses. We can see that from way back a great deal of attention has been paid to
the house on the right, a little to the house in the middle. The house on the left is the
poor relation. The problem here is that we do not yet really know what this user might
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want. It is important for this house to find the Human Dimension in ICT. Just as an
interior architect takes the Human Dimension into account when he is designing a
room.
The last thing I want to say about the houses is that information systems have nothing
to do with houses. This is the worst analogy you can possibly imagine, but at the
moment we have nothing better.
An information system is a piece of production machinery. Data go into it and refined
data or information come out of it.
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Formal definition
Looking through the dictionaries we can find many definitions of the term architecture.
On two occasions I have tried to worm out of a real (physical) academically trained
architect precisely what architecture is, and in both cases there was ten minutes’
silence!
In my perception, and that of Gartner, architecture is a coherent set of principles, rules,
guidelines and standards that are used in the design and the construction of information
systems and the information supply as a whole. So it is a sort of metaterm, within which
certain archetypes can perhaps be distinguished.
IEEE, an extremely respectable society, sees architecture as a first outline. At first sight
this seems rather a trivial definition. But what it should say is “the highest level of
Conception of a System, where the most important stakeholders agree”. Then the
definition begins to acquire more substance.
What is important in this definition is that architecture is not a feature of a system in
isolation, but that the environment of the system must also be taken into account.
So the system must fit in with its environment architecturally.
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Gap or Challenge
The managerial need for architecture is extremely great. We are living in one of
mankind’s greatest periods of transition. Historians looking back from the year 10,000
will be amazed that in an extremely short space of time of no more than 100 years on
the threshold of the third millennium, the whole of society was radically transformed.
Between 1950 and 2050 we saw a dramatic changeover from unwieldy, clumsy, stupid
computers to a fully ICT enabled society. A society in which ICT helps people and
business to develop to the full.
We are currently in the midst of this turbulent age. Everything around us is being ICT
enabled and has to be on the Internet. New technologies are washing over us. It is
logical that now and again we feel we are drowning in the chaos of new ICT challenges.
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The term ICT architecture has made its entrance in the software industry in this need
for “order and measure”. There is a fundamental need for “order, measure, discipline
and beauty” in the information supply, in software products, in ICT services and even in
the development process as such.
Given solution patterns for given problems, given style in given environments, given
constructions under given circumstances. Or ICT architecture: a coherent set of rules,
guidelines, (meta) models and standards under which an information supply (of a part
thereof) is designed and implemented.
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Major changes in an integrated manner
Elaborating a little on the previous picture, we can see that senior managers are
confronted by a wide variety of interesting trends:
 The Internet is radically changing the way in which we do business and the
associated business models (CRM, ISCM, XRP, e-business B2B and B2C).
 New technologies such as voice recognition, advanced technologies in the field of
knowledge management, mobile communication, ubiquitous computing, security
technologies, data warehousing & business intelligence, call centres and content
technology are coming to the fore
 As a “global” trend we can see that the art of cooperating is becoming more
important than the art of competing. Traditional trade boundaries are starting to blur.
Entirely new markets and target groups are coming into existence. We would argue
that technology is a catalyst for business developments. Through the integration of
technology - and by making use of architecture -, a quick advantage over
competitors can be gained.
By considering and developing technology together with management you can respond
more quickly to the trends of tomorrow. With this approach technology is becoming
embedded in the boardroom and decisions about it are no longer taken in smoky back
rooms.
All these trends require a complete review of business activities. This requires a
thorough, structured and integrated approach. Ad hoc solutions will no longer do. In
short, this requires simple pictures that can serve as an atlas for piloting your business
into the Information Age.
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What it’s all about…
Architecture is the means of planning and directing.
Some important objectives for the use of architecture
 Atlas for senior management
 Complexity control
 Framework for implementation
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
Communications tool
Atlas for senior management
Architecture can be compared to the development plan for a town. It must be clear at a
glance how business processes work, how the business is developing and how
technology has been integrated, and how clients are connected to it.
Apart from the information supply, there are also all kinds of other assets that are
constantly changing, that have to be adapted, that have to be adjusted. Examples
include the organisational structure, the staff, the buildings, the means of production.
To synchronise the changes in these things with the changing information supply you
need architecture as the atlas. An atlas for maintaining the overview.
It is therefore something of a pity that while the senior managers of businesses may
well concern themselves with the architecture of their main building, they pay scant
regard to the architecture of their information supply.
Complexity control for the ICT manager
Architecture is used so that the ICT manager can maintain an overview. So how do I
ensure that I can still see the wood for the trees? The answer is by “delegating” the
complexity downwards. In this case architecture ensures that you as a manager can
look at the whole, and then at the various individual parts and the part they play in the
whole.
Architecture as a tactical tool has a “choice limiting effect” and is therefore the best
weapon for tackling complexity.
Framework for execution
Since many transformations in the information systems consist of complex system
integration tasks and several projects are often running simultaneously, the important
thing is that there is a common framework. Because although you can develop things
separately, in the end everything has to work with everything else.
What is important here is that clear agreements are made, which processes come first
and what comes afterwards. You make a plan and you specify the order in which the
plan is made or built over.
Communications tool
Architecture is primarily a means of communication. The framework, the atlas… they
are all utterances. It shows how a given system fits together.
As has been said repeatedly, there are many stakeholders surrounding the subject of
architecture. The different architecture models must therefore be usable as
communications tool to ensure that a commonly accepted information supply is
designed. PR is very necessary in this respect.
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Architecture’s role in the transformation process
The architecture at enterprise level and at project level are anchored in the way in
which Cap Gemini tackles major projects, where business and ICT are transformed
“concurrently”.
In the phase that is referred to here by scope, architecture is used for arriving at the
correct demarcation and for including the consequences of the environment.
The transformation programme is implemented in a number of transformation projects,
each of which transforms part of the business and the ICT systems. This is what
happens with the Cap Gemini Programme Management approach.
Each project begins with a project-level architecture.
This picture illustrates very clearly that architecture is a tactical tool, that is, a tool for
regulating the layout.
The upper levels impose restrictions on the lower levels, while the lower levels give
feedback to the upper levels. Such an arrangement is consequently undergoing
constant adjustment and is therefore in perpetual motion, which my web artist has
made clear.
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Influences
An interesting question is how do you come by an architecture?
Even more interesting is the question, by what factors is architecture determined? To
avoid embarking on a 45-minute lecture, I will simply highlight the factor “prevailing
culture”.
It is extremely important that the information supply fits in with your business. Which
means that the architecture is influenced by the prevailing culture.
For instance:
When I was young, I was an account manager and had a financial client who needed a
credit information system. The platform was IBM, IMS, CICS and PL/1. Yes, it was a
long time ago. At the time somewhere abroad an information system for a large bank
had just been completed, with the same functionality and on exactly the same platform.
I flew to that particular country with a number of bank managers. Functionally the
system met the requirements perfectly; the only problem was that the screens and the
output were in that foreign language. But that was a translation agency level problem.
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However….. the credit information system was shot through with that particular foreign
mentality. You do what the boss says and it is unseemly to question what he says. You
will understand that this is not the way right-minded Dutchmen do things. Every
authorisation had this patriarchal slant. So because such a business culture is so unDutch, the bank in question had the application built itself, by Cap Gemini in the
Netherlands of course.
This cultural aspect is also extremely important with package software.
You will also find culture in the management and the strategy determination (actually in
all aspects of a business). Interaction between people is culturally determined. So it
must also be included in architecture.
Yet I want to raise a warning finger against too much cultural dependence. Culture often
consists of old, set patterns. And you would not want your information supply to
perpetuate such patterns!
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The CG architecture approach - 1
Look before you leap. This certainly holds for transformations in ICT. Which is why Cap
Gemini has defined a number of clear steps in its architecture approach:
Why and What
before we dive into the
How, What with and When.
In architecture the how question is very important. People generally do think about what
they want, but it is often not at all clear in what way this must be achieved and whether
it is actually feasible. Together with the client an explicit choice must be made for the
resources and strategies to be employed. I want to stress explicitly that it is not a
question of phasing here: so not the why and what first; but it is first and foremost a
matter of answering all the questions.
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The CG architecture approach - 2
In the IAF Framework we distinguish four architecture areas, along the horizontal axis:
1. Business architecture : products, services, business processes and organisation
structures
2. Information architecture: a picture of the information and knowledge flows in and
around the organisation. This is in fact an aspect of the business architecture
3. The architecture of the information systems
4. The architecture for the technological infrastructure
Along the vertical axis we have placed the five tricky questions that are necessary to
computerise properly.
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The “what” bar is the conceptual layer. This is where the needs of the users and the
organisation play a dominant part.
The “how” bar is the logical layer. This is where we look at solution forms separately
from the physical implementation. So this requires the most creativity.
The “what with” bar is the physical layer. This is where the rules are formulated on the
basis of which products and suppliers can be selected.
These three layers bear a strong relationship to the three houses that I showed you 15
minutes ago.
In the 20 cells we then have we can enter the principles, rules, guidelines, metamodels
and standards that we want to use. Also very important are the relationships between
the cells to ensure a consistent architecture.
So this matrix contains the whole architecture process. The columns define the different
parts of the information supply. The rows support the progress in the decision-making
process.
This framework too can be used as:
 an atlas,
 a communications tool,
 for complexity control and of course
 a framework for development.
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Cap Gemini Architecture
In physical construction they talk about schools of architecture. Of course every
architect delivers a unique product. Every architect has his own creativity. But within a
school there are certain characteristic things. For instance, anthroposophical buildings
are rounded off.
Would this be the case with ICT architecture as well? We certainly think so! Which is
why we have begun to list a number of common features under the working name
“Utrecht School”.
Since you can all read, I will not deal with them all. But I shall explain two of them:
- merging of business and ICT. We only believe in integrated solutions based always
on a business case, with clear business benefits
- we believe in an architectural approach to security and management. These
features must be included on an integrated basis.
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The Architect - 1
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Last week we spent two days discussing architecture with about 100 people, half of
whom were from the academic world. The final conclusion was that we will probably not
arrive at a scientifically watertight definition of the concept “architecture” in the short
term; a definition that is also sufficiently discriminating. But nor is that necessary. It is
more important to describe the work of the architect clearly.
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The Architect - 2
The ideal architect should be a man of letters,
a mathematician,
familiar with historical studies,
a diligent of philosophy,
acquainted with music,
not ignorant of medicine,
learned in the responses of jurisconsultis,
familiar with astronomy and astronomical calculations.
Vitruvius, ca. 25 BCE
In modern parlance:
An architect must:
 be able to listen and formulate carefully,
 have a feel for stereometry and three-dimensional relationships,
 have a feel for measure, order and harmony,
 demonstrate a feel for factors that affect human well-being,
 be acquainted with the trends of the past,
 and be a practical philosopher.
So a little bit of Plato, but a lot of Pythagoras
This also appears to contain some useful elements for the ICT architect.
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The Architect - 3
This picture positions the architect between the client and the developer / the builder.
1. The architect represents all the stakeholders,
 all the client groups,
 internal users and end users,
 indirect users,
 the future maintenance staff,
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 the future operating staff,
 the developers,
 standard setters
and is director of the image-forming process.
2. He makes and monitors the integrated concept.
3. He is responsible for a well-defined task going to the builder.
A relationship based on trust with the principal is important.
In short, more than 50% of the architect’s effort consists of observation, and therein lies
the fundamental difference between the architect and the designer.
The architect produces
 models that visualise the appearance and the behaviour of the system as the clients
and users will experience it. With these models they must be able to judge whether
the future system is going to meet their requirements.
 prescribing models, concerning the structure and the cohesion and cooperation
between the components.
 models for judging the implementation of the other quality attributes, such as
security, performance, costs, business benefits.
It is in our view important that the architect maintains supervision over the detailed
design and the realisation of the system. This guarantees that the system is
implemented in accordance with the architectural description.
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The Architect - 4
At Cap Gemini we recognise different types of architect.
A regular architect is skilled in one of the columns of the IAF framework, the technical
infrastructure, for example.
A senior architect is skilled across the board; that is, he also has a profound
understanding of the requirements in the other layers of the IAF framework and the
interrelationships.
Since an architectural assignment is often carried out by a small team of specialised
architects, a managing architect is needed who has developed these management
skills.
Top right we position the principal architect. This is a managing architect who also
acquires assignments independently and negotiates with the client about them.
At Cap Gemini we anticipate that architects are going to be playing an increasingly
important role in the design of an information supply. If an information supply functions
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poorly or, like a straitjacket, has business activities by the short hairs, in the future
everyone will point the finger at the architect. Which is why Cap Gemini, worldwide, has
begun an internal certification programme to ensure the quality of our architects.
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Résumé
The main points I wanted to bring to your attention are:
1. The three aspects of architecture, visualised in the three houses: give all three of
them the proper attention!
2. Use the IAF framework for a coherent and mutually consistent view of all your
architecture decisions.
3. Ensure that you position the architect properly.
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