architecture. These approaches are mostly aimed at the breaking down
of IT support into autonomous building blocks that can be developed,
maintained, and changed independently of each other. In this way,
changes to parts of the provision of information can be carried out
quickly because they are restricted to clearly defined components. This
is the well-known "Lego principle."
The process side of architecture is generally underexposed. The
way in which architecture is employed within an organization, however,
is crucial in achieving the agility required--and therefore the primary
focus of this book is the process side of architecture.
The critical success factor for working under architectural guid-
ance, in the present dynamic time, lies in the way that architecture is
employed within an organization. We present a way of using architec-
ture that is focused on enabling change.
The following are examples of architectural principles that result in an
architecture (i.e., a product) that is explicitly designed to adapt itself to
Data must be registered and maintained in one location.
Applications may retrieve data only from an authorized source.
Clearly defined uncoupling points must be introduced between all
main processes and information provision services.
In IT systems, control and execution mechanisms must be imple-
Presentation of information, business logic, and registration of data
must be implemented separately.
Control is applied to the interfaces instead of the internal working of
the systems (the "black box" approach).
Standard interface and integration techniques will be used.
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