Software Development: What is SOA?

Service-Oriented Architecture (SOA) is a set of guiding principles, processes, and methodologies for software development and design in the form of interoperable components known as services. These component services are really specific business functionalities that are reusable, easy to modify and will not influence or break calling client programs when changes to the service occurs.    

 One goal of SOA is to broadcast the availability and the type of services it provides to the consumers of these services like web-based applications. An example would be several departments in an organization that may have their own development and deployment of a particular SOA service in their own implementation language. There needs to be a way for other client applications to access these services using a well-defined interface. XML is usually the standard used for interfacing with SOA services.      

The ability to integrate different applications with different formats and platforms is one benefit of SOA.  SOA does not use APIs. Instead it uses protocols and functionality to define the interface. A very important term, a bit ironic, is the entry point for the SOA implementation which is called an endpoint.

One requirement for service -orientation is loose coupling with the underlying technologies, host applications and their processes, and the operating system. The reason for this is reusability. Diverse client applications need to access these services and in order for it to be successful, the component service has to be modular, has a specific business functionality being solved, and does not have a lot of baggage on which it is operating under.