"SOA for the real world" by Ash Parikh and Murty Gurajada, JavaWorld.com, 11/29/06
The focus of most SOA implementations today is on the service layer and often extends to the registry to publish and discover services. This approach to SOA is easy to comprehend. As mentioned previously, the concept of exposing services is not a new one. Most software architects and engineers have years of experience building services and should be comfortable applying their knowledge to expose services using the newer Web and XML technologies. Once the services are implemented, registry products based on UDDI (Universal Description, Discovery, and Integration) are used to publish and discover them.
With this architecture in place, enterprises already have much better visibility than was ever possible before WSDL (Web Services Description Language) and UDDI standards emerged on the scene. Unfortunately, it is because of this pleasing ROI that most implementations stop short in their tracks—that is, until it becomes apparent when trying to scale their model that a service layer with a registry is simply not enough for true SOA ROI.