Information Technology Reference
In-Depth Information
requirements to be fulfilled by our architecture in the context of IS solution building.
Essentially, the function of a building architect can be summarized as follows (Buffam, 2000;
McConnell & Tripp, 1999):
The architect creates in his or her mind a concept of the overall form of the
building to fit the intended purpose. This same architect creates a tangible set
of blueprints that express his or her concept with sufficient clarity and rigor
that the building owners can verify that the design satisfies their needs. Also,
the architect — before committing to construction — can verify, through
inspection, simulation, and calculation, that the building will stand up to its
anticipated load, withstand environmental conditions and requirements, and
meet regulatory standards. Tellingly, craftsmen can construct a building
fulfilling that concept.
Accordingly, in the IS context, we could provide a number of reasons to support the
provision of an architecture. First, we need this architecture to ensure that the IS environment
is aligned with the organization's imperatives. Namely, this architecture provides the basis
for IS professionals and organizational leaders to ensure that the proposed system is properly
aligned with the mission, objectives, and processes of their business. Such an alignment
supports typical organizational goals as enhancing the capabilities of existent information
systems and taking advantage of new strategic opportunities. Second, we need the architec-
ture to help build an IS environment that can be easily changed and extended, so as to retain
its alignment with changing business imperatives in the organization. Third, we need
architecture to communicate appropriate views of the solution to, and among, the various
stakeholders, so as to ensure that the solution gets built on time and within budget, while
fulfilling the intended requirements. Fourth, we need architecture to help keep our IS
environment (and its supporting processes) intellectually manageable. We recognize that
information systems are complex. The control of complexity, and through it the ability to keep
our systems understandable, is the biggest single challenge in the IS construction. One of
the most important functions of the architecture is to support a “divide-and-conquer”
approach. Other functions include to provide a framework for making and communicating
technology choices, to give us freedom of choice of information technology (IT) components
through component interoperability and through component portability, and to maximize our
efficiency in building and evolving the IT environment through reuse of earlier work. In other
words, it is too important for IS/IT professionals to neglect the essence of architecture — the
reminder of a whole sequence of organizational and technological concerns.
The WHAT of Architecture in IS
The architectural context of IS solution building could be considered as a set of
principles acting on and intimately integrated with, the total process of creating IT solutions.
This process is often formulated in several distinct directions, such as the common-
component sense, the design sense, the blueprinting sense and the framework sense (Pour,
Griss, & Lutz, 2000; Bourque et al., 1999; Repenning et al., 2001; Zachman, 1987):
•
The
Common-Component Sense
: This sense is based on the idea of reusability; namely,
design is based on leveraging reusable standard components, subassemblies, frame-
works, patterns, and idioms. To understand its significance, we can compare a
traditional IS design with one guided by architectural principles. Traditional IS design
