SOA - From Vision to Practice

I have just been reading the September 2009 issue of the Microsoft Architecture Journal which is focused on SOA. The foreword starts off by referring back to the report 'Understanding SOA' that David Sprott and I wrote for the very first issue back in 2004. As editor Diego Dagum puts it, "the main difference with the article that we published in the early days is that, this time, thoughts have emerged as a consequence of a practice; in 2004, thoughts had emerged as a consequence of a vision."

The inevitable "SOA is Dead" discussion is raised in the report Model- Driven SOA with"Oslo". But that report and others in the journal really serve as reminders that SOA is in reality still in its infancy, and we are still developing best practice, and in Microsoft's case at least, the modeling tools to support it.

Encapsulating best practice in modeling tools is essential if we are to

• move beyond perceptions by some that "SOA is a technology"
• demonstrate business value by making the SOA investment more relevant and 'visible' to business sponsors

That's a key reason why we ourselves have invested so much in our CBDI-SAE Meta Model for SOA and the associated UML profile that enables users to move from business models to implementation in a consistent and traceable manner.

It would be interesting to see how we might implement that in Microsoft Oslo. Oslo offers the promise of "the model is the code". Not surprisingly, Microsoft do have a slightly myopic view of the world that typically extends only as far as their own technologies. Though it may not be a business modeling language, Service Component Architecture (SCA) that I have been looking at in more detail this month does already provide a model-driven approach to modeling the Service Implementation Architecture, which is a good level of abstraction at which to consider "the model is the code". Unfortunately, SCA isn't implemented on the Microsoft platform. It's a pity that wheel is going to be reinvented I guess.

Nevertheless, it is good to see Microsoft continue to develop the SOA vision and turn it into practice, and in particular to embed that vision deep into their platform and tools, such that SOA becomes just 'business as usual'.