Service-oriented architecture
A service-oriented architecture (SOA) is a collection of services that communicate with each other, for example, passing data from one service to another or coordinating an activity between one or more services.
Companies want to integrate existing systems to implement IT support for business processes that cover the entire business value chain. A variety of designs are used, ranging from rigid point-to-point electronic data interchange (EDI) to Web auctions. By using the Internet, companies make their IT systems available to internal departments or external customers, but the interactions are not flexible and are without standardized architecture.
Because of this increasing demand for technologies that support connecting and sharing resources and data, a need exists for a flexible, standardized architecture. SOA is a flexible architecture that unifies business processes by structuring large applications into building blocks, or small modular functional units or services, for different groups of people to use inside and outside the company. The building blocks can be one of three roles: service provider, service broker, or service requestor.