In modern organizations, business processes and information systems form
a symbiotic relationship: many leading-edge business processes would be
impossible without computers and most of the justification for
information systems investment comes from their support of business
processes. However, the domains of business and computers are very
different: business focuses on entities, processes, locations, people,
times, and purposes while computers consist of data, the programs that
manipulate the data, and a technology infrastructure. For information
systems to be usefully applied to problems in the real world, there must
be mechanisms to relate the two domains.
A number of modeling techniques have emerged over the years to bridge
these worlds, such as flowcharts, entity-relationship and process flow
diagrams, and data flow diagrams. But each of these techniques is
specialized for a different purpose. By concentrating on one aspect, the
individual technique loses sight of the overall information system and
how it relates to the enterprise and the surrounding environment.
Flowcharts, for example, focus on the operations performed by a computer
and their sequence. Flowcharts are useful for showing algorithms, but
pay little attention to the data structure processed by the algorithm;
data is considered only as it is being operated on.
An
architecture provides a means of describing and relating these different
views of an information system. The pioneering work in an architecture
for information systems was done by John Zachman of IBM who proposed, in
1987,
a framework for information systems architecture (ISA).12
This initial work defined an architecture relating data, function, and
network models, which are the what, how, and where of an information
system.
In 1992, Zachman extended ISA to include three additional views: people
(who), time (when), and motivation (why).13
It may be more convenient to think of the people view as the challenge
of allocating work and structuring authority and responsibility in an
organization. Similarly, time is the challenge of optimizing the
utilization of resources while satisfying commitments. Finally,
motivation considers the issue of organization objectives and strategies
for achieving them.
