The movement toward smaller, focused SOA efforts -- and away from big, enterprisey SOA -- seems to have been gaining a lot of momentum as of late.
Some SOA services may surface at the enterprise level, but most will serve focused, local business needs. And that's okay.
Lorraine Lawson over at IT Business Edge senses this new thinking in the wind, which may help reframe the whole Is-SOA-Failing debate. The SOA-is-all-about-the-enterprise mindset is being replaced by more pragmatic thinking -- simply that SOA works better in some situations than others. As Lorraine put it: "I’m seeing more of this type of cautionary advice, which is interesting because when I first started reading about SOA, everyone seemed to argue that SOA needed to be enterprisewide to achieve its full potential."
There's been plenty of discussion across the blogosphere, analystphere, conferencesphere, and mediasphere about how SOA has not been quite making it because it hasn't been surfacing on the enterprise level. Instead, SOA has been mainly seen in departmental or single business unit settings.
Is this a bad thing?
One long-time proponent of more targeted SOA -- versus broader enterprise sweeps -- is ZapThink's Ron Schmelzer, who argues that in too many cases, the business case for enterprise SOA is not justified:
"The rationale goes that SOA is an aspect of Enterprise Architecture and therefore its scope is enterprisewide, or because it is so important and strategic, it must be implemented at an enterprisewide level. Other IT practitioners are simply used to implementing all of their major initiatives enterprisewide, so why should SOA be different?"
Ron goes on to say that "SOA is simply not appropriate for all problems, and even for problems that need to be solved enterprisewide, not all parts of the solution should be service-oriented.... "Knowing when and how to apply SOA is 80% of the battle."
Ron also observes that "well-scoped SOA projects are often remarkably successful. Most case studies of SOA success relate to organizations fixating on a particular business problem, perhaps at even the departmental level, and solving that in a service-oriented way. The champions of SOA know full well that success comes from focusing the solution on a particular problem and solving it well."
In Ron's words I hear echoes of the "Guerrilla SOA" approach advocated by Jim World-Wide Webber, reported in this blogsite the other month. Jim described Guerrilla SOA as well-targeted, lightweight engagements to address specific business problems, versus the Big SOA approach promoted by many vendors.
The bottom line is that there are many services that will come out of SOA that will never see the light of enterprise day. Last year, I heard Tracy Legrand, chief architect for the financial planning firm Ameriprise Financial, aptly sum up the mixed role SOA will play in individual business units versus enterprise wide.
As Legrand explained from his own experience, not every service is reusable across the enterprise, and some may never get reused at all. Legrand's team actually divided its services into three separate tiers: enterprise reuse, shared reuse, and specialized reuse.
"At the enterprise level, we had very few services that we identified as enterprise in nature," he related. However, the leading enterprise-reuse service — customer management — delivered up to $10 million in savings to the company, he added.
The next level of reuse, shared reuse, occurred at the line-of-business level, versus enterprise reuse. Then there were specialized, services "that frankly weren't intended or expected to be shared to any great degree," Legrand said. But it still was worthwhile to build these services using SOA tools and technology, he said.