West Coast travels and SOA

It’s a long trip travelling east-to-west, fighting the jet stream along the way, from PHL to SFO. However, it affords the traveler a great chance to catch up on a ton of reading. Since I travel quite a bit, I am the kind of person that keeps a stack of material to read for just such an occasion. This trip allowed me to get through a two-inch thick manila folder of great open source articles (and about 10 packs of US Airways’ “Fancy Cashews & Honey Sesame Sticks”).

The topic I’d like to throw open for discussion here is the correlation between open source and services-oriented architecture (SOA). I’ve come across a few analysts that don’t see much (if any) correlation between the two, but thankfully they seem to be in the minority (and I won’t mention them by name). Open source is an enabler to SOA, and although not all SOAs are built completely with open source components, the modular, loosely coupled nature of open source components make them ideal for many SOA implementations. And, with approximately 80% of CIOs making SOA a priority, this is a worthy discussion.

But, a step back is probably in order. If you ask 10 people to define SOA, or even “architecture” for that matter, you will most likely get 10 different definitions. My view (or definition) of SOA in one sentence: a defined, governed infrastructure environment (or parts thereof) where business rules & processes have been decomposed into a set of registered, discoverable services, which, when invoked, perform a function and perhaps return a result. The goal: leverage existing assets (ie legacy applications and mainframes) and the build or acquisition of new assets in an intelligent, modular approach such that component reuse is high and solution developers can focus on their core value-add rather than having to reinvent parts of the wheel for every solution. Analyst firms like Kennedy estimate that organizations can save 30-40% on their infrastructure costs “because clients can easily reuse software once it is developed”. But another huge benefit of building a SOA environment and thinking through the business processes that are core to the business is the ability to more effectively link business rules with the infrastructure and thereby create a paradigm where the business rules drive the IT infrastructure, rather than the other way around. At Unisys, we call this 3D-VE or 3D visible enterprise, where the linkages are defined all the way from a company’s vision, down through its business processes and applications, and into the IT infrastructure. By seeing how it all fits together (or, in many cases, doesn’t) and understanding the impact of changes before they are actually implemented, it is a lot easier to build a future state environment like the one I just described.

The hard part, of course, is developing a governance model that is used by the entire organization and coming up with the right level of “granularization” for the service components. Take the presentation layer as one example. User sign-on. Security. Policies and access models. Interoperation of the security components with the rest of the middleware environment. Companies need to think through all this to get it ideal, and it will have ripple effects throughout the infrastructure. But, one of the beauties of open source is that you can start with a low cost without spending a fortune and being stuck on the path of a purely proprietary implementation. The hottest SOA areas right now are around portals, integration, business intelligence, and security, and there are plenty of open source components to help.