"Service-Oriented Architecture" (SOA) and "Software as a Service" (SaaS) are two driving forces in software architectures today. In this article, I explore how to grow a local SOA into a federated SOA distributed over the Web to both use and deliver SaaS. In the process, I examine how "mashups" relate to SOA over the Web and how, if used inappropriately, they may circumvent some of the benefits of SOA and SaaS.

SOA

Service-oriented architecture has established its value in enterprise systems as an architecture for integration, consolidation, and reuse. This has provided a path to integrate and consolidate legacy systems onto a consistent platform for growth and agility going forward. The building blocks of the SOA are services that all adhere to the pattern in Figure 1.