and how it is arranged; who should have access to what data;
whether data should also be accessible outside the organization;
which data are shared and which are not; which standards are
used for data exchange; and the like. The data architecture also
contains, when appropriate, the definitions of companywide data
and their interrelationships (i.e., company data model).
·
Application Architecture--The principles and models relating to
the organization's software applications. The application architec-
ture provides the implementation principles of applications (e.g.,
components versus "best-of-breed" packages); the interrelation-
ship between applications; the software environments to be used;
which are shared applications and which are not; how authoriza-
tions are arranged, and the like.
·
Middleware Architecture--Common organization-independent
software components that allow applications and end-users to
work together across the network such as message queuing, TP
monitoring, ORB, RPC, EDI, XML. Middleware is the software that
interfaces between the network and organization-specific applica-
tions. Part of the middleware architecture is the policy on middle-
ware product resources, namely what middleware products the
organization will use, when to use which product, and how these
products work together.
·
Platform Architecture--The platform architecture focuses on IT
equipment. These include the mainframes, desktops, terminals,
peripherals, and their operating systems. The platform architecture
contains the resource policy for this equipment and sets standards
with respect to scalability, availability (contingency plans), and
compatibility.
·
Network Architecture--The set of principles and models relating to
connectivity of devices or the technical network of the organization
(LAN, WAN). The network architecture contains prescriptive state-
ments and models for the realization of the network (dedicated
lines, private lines, telephone lines, wireless), network topology,
bandwidth, communication and transmission protocols to be used,
control and routing hardware and software, and so on.
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