The most recent trend in the development of technology environments that
match the scope of industrial operations has been the move toward service-oriented
architectures (SOAs), which were introduced in Chapter 16. According to the
Organization for the Advancement of Structured Information Standards (OASIS), an
SOA is “a paradigm for organizing and utilizing distributed capabilities that may be
under the control of different ownership domains. It provides a uniform means to
offer, discover, interact with and use capabilities to produce desired effects consistent
with measurable preconditions and expectations.” This is not too different from the
initial definition of a computer operating system that enables the various functions
within a single computer.
The difference is an SOA provides the distributed infrastructure and services
that turn a distributed multiple computer system from multiple vendors into a
homogeneous system across separate computers. SOAs can support different
computer domains. For example, NetWeaver from SAP is an enterprise SOA (ESOA)
designed to support a business enterprise domain, while ArchestrA from Invensys
is an industrial SOA (ISOA) designed to support a real-time industrial domain. The
development of SOAs is starting to significantly diminish the barriers to systems
integration, providing common computer domains across multiple systems. Although
these SOAs are still in their infancy, they will have a significant impact on industrial
automation and business computing for decades to come.
The need to connect different intelligent systems and devices from different
suppliers into a single interoperating environment has been felt ever since the
introduction of the computer to industrial and business operations. The evolution of
technology and approaches to support this need has been long and gradual. A very
significant shift has taken place over the past few years from an intense focus on
integrating the intelligent technology to an intense focus on solving business problems
enabled by the technology. This is a major step forward for industrial automation
because integration in and of itself adds no value; solving real business problems does.