SOI is also an abbreviation for Silicon-On-Insulator.
Service-oriented integration (SOI) is defined as integrating computing entities using only service interactions in a service-oriented architecture. Service-oriented integration addresses problems with integrating legacy and inflexible heterogeneous systems by enabling IT organizations to offer the functionality locked in existing applications as reusable services.
In contrast to traditional enterprise application integration (EAI), the significant characteristics of services-oriented integration are:
Well-defined, standardized interfaces – Consumers are provided with easily-understood and consistent access to the underlying service.
Opaqueness – The technology and location of the application providing the functionality is hidden behind the service interface. In fact, there is no need for a fixed services provider.
Flexibility – Both the providers of services and consumers of services can change - the service description is the only constant. Provided both the provider and consumer continue to adhere to the service description, the applications will continue to work.