Twenty percent of SOA value from service reuse; where's the other 80%?

Is service reuse a worthy part of the SOA value equation?  This is a question that has been endlessly debated in recent years.

Mashups may hold the key to long-term SOA value

For example, last month, we quoted Forbes' Dan Woods, who argued that companies are focusing on building SOA-based services that will be available for reuse as soon as they are tested and released to the registry/repository. Perhaps, he says, we should worry less about reusability at the beginning phase of service development.

Or, even if reuse does deliver ROI, it may only have a limited reach. Marc Rix recently weighed in on the topic, suggesting out that "basing SOA on reuse only modernizes 20% of IT and, thus, does not yield agility." The other 80% of the equation, he says, is based on deployment of data services.

He arrived at the 20% figure by calculating the fact that reusable services tend to be the most popular or mainstream services, and "tend to orbit around relatively static business data (employees, customers, vendors, suppliers, etc.)." Building and deploying these services means relatively immediate reuse, and therefore, ROI. However, there's little ROI beyond the immediate rush, he says.

For SOA value, Marc says, look to the " Long Tail of IT" -- data taken out of core enterprise systems and manipulated by business users, in applications such as business intelligence and analytics. "This is where business is really conducted and this is where SOA is really needed," he says.

Why I hear Marc saying is the real meat of SOA will be seen in more dynamic, user-created (or at least user specified) composite apps. Enterprise mashups come to mind in this context. In these situations, end users can create their own interfaces as business requirements demand. They can be quickly built and used. However, what is needed is a way to make this possible within a governed framework. With SOA governance and best practices applied on this end at the architectural level, organizations have assurance that these enterprise mashups are subject to the same security and vetting as core SOA services.