At the top of the architectural framework in Exhibit 6.1, it reads
"Business Objectives," indicating that all domain architectures serve
one or more specific business objectives.
The horizontal axis of the framework indicates the various possible
objects of architecture, which may lead to separate domain architec-
tures. The vertical axis of the framework shows that each domain archi-
tecture can be divided into three conceptual levels:
The highest level is the level of general principles. These reflect
the common vision of business and IT top management. The
general principles apply to everyone and must, therefore, also
be comprehensible to everyone.
The second level contains the concrete policy directives that give
shape to the general principles. These directives are often more
specialized than the general principles. They are a translation of
the general principles into concrete details for each domain
architecture. Standards and guidelines can be found at this
level. Together, the general principles and policy directives are
referred to as the architectural principles.
The third level is the level of the specific models. Depending
on the object of architecture, they may take different forms.
Graphic design often plays a major role here. The models are
generally the realm of specialists.
In Chapter 3 we saw that, in addition to the dimensions of object of archi-
tecture and level of architecture, there is also a time aspect attached to
architecture, the today, tomorrow, and next-minute architectures. Placing
this time dimension on the architectural framework, we see that the
general principles and policy directives are instances of next-minute
architecture. They give definite direction to the decisions that must be
made today. The models may serve as today architecture or as tomor-
row architecture. These give a view of both the existing and the desired
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