It is often said that the best way to understand something is to gain knowledge of its history. Service-orientation, by no means, is a design paradigm that just came out of nowhere. It is very much a representation of the evolution of IT and therefore has many roots in past paradigms and technologies (Figure 4.20). At the same time, it is still in a state of evolution itself and therefore remains subject to influences from on-going trends and movements.
The sections that follow describe some of the more prominent origins and thereby help clarify how service-orientation can relate to and even help further some of the goals from past paradigms.
Object-Orientation
In the 1990s the IT community embraced a design philosophy that would lead the way in defining how distributed solutions were to be built. This paradigm was object-orientation, and it came with its own set of principles, the application of which helped ensure consistency across numerous environments. These principles defined a specific type of relationship between units of solution logic classified as objects, which resulted in a predictable set of dynamics that ran through entire solutions.