SOA Adopters Discuss Best Practices - MetLife's approach to building out an SOA infrastructure shares some similarities with the snowball metaphor Microsoft sometimes uses to describe a recommended way to implement an SOA paradigm -- again, the idea being to start small. As the snowball picks up momentum, it grows bigger.

"The notion of starting with a specific business requirement and taking an experimental and experiential point of view on the whole process is definitely a good approach," says Dan Woodman, industry technology strategist for Microsoft's financial services team. "SOA is not something you can just take on and say, 'We're going to implement SOA.'"

Allstate's IT department focused first on individual domains, some of which boast their own eight- and nine- figure IT budgets, and chose platforms and technologies that were most appropriate for each, according to Abbattista. Two and a half years ago, for instance, the company revamped its claims processes. In this particular space, it made sense to use .NET protocols to expose services and create a type of building block architecture for claims, Abbattista says. Meanwhile, Allstate's premium domain is mostly Java-centric.

Another key to successful SOA implementation is governance. Specifically, organizational structures need to be in place to foster collaboration among business lines and movement beyond specific silos. Allstate, for instance, has a very federated development organization, according to the company's Abbattista, and the carrier's SOA development standards and architecture are centralized.

"The baseline is governance" when discussing SOA best practices, says TowerGroup's Gorman. "We're seeing things like enterprise steering committees, business architecture models, councils of architects, project management offices and certification of reusable services. Those are the guiding principles from a governance perspective."