Support for Service Component Architecture (SCA) offers a way to construct applications based on Service-Oriented Architecture (SOA). The support uses the Apache Tuscany open-source technology to provide an implementation of the published SCA specifications.
SCA is defined in a set of open specifications produced by IBM® and other industry leaders through the Open SOA Collaboration (OSOA).
You can use SCA to assemble and compose existing services in your enterprise. The key principle of SOA demonstrated by SCA support is the ability to use your existing services to create new ones.
Another key objective of SCA is to highlight the ease-of-use characteristics of SCA service development in Java. This is accomplished by demonstrating annotated Plain-Old Java-Object (POJO) components deployed using simple JAR packaging schemes, an easy to use assembly model, and wiring abstractions that enable service definition over different transports and protocols.
SCA enables your organization to move quickly into the world of SOA, as follows:
SCA in WebSphere® Application Server follows the definition of the technology as documented by OSOA. Defining a set of compliance test suites was not part of the OSOA charter, so the implementation provided in this product uses the following specifications as guiding principles. However, IBM provides an implementation that adheres strictly to our interpretation of the specifications.
See the "Unsupported SCA specifications sections" topic for restrictions and limitations that are unsupported at this time.
As already noted, multiple specifications are defined at OSOA, as well as Tuscany extensions provided in open source that go beyond the basic mission of WebSphere Application Server. Each vendor can decide which aspects of SCA apply to their product. For WebSphere Application Server, the focus is on enabling compositions as services, Java components, and integration of key qualities of service-like transactions and security.
SCA can enable mediations, business rules, and business process execution language to be treated as any other service, and while WebSphere Application Server provides the mechanisms to wire services that are implemented in those languages and environments, the product does not provide native support to host those kinds of service implementations.