Gilpin uses the telecommunications industry to illustrate the concept. SOA is the lingua franca that bridges all of a telco's services -- land line, Internet, mobile, television and more -- so they can be delivered in a unified manner on a carrier's Web site. This setup could even be extended to the company's retail outlets, where it would enable salespeople to see details of service packages on a monitor.
With SOA, all of that could be more tightly integrated, allowing a company to market, provision and create bills for combined and bundled services from all sources.
Each of those systems could run on different underlying technologies, Gilpin explains. "Land lines might live on a mainframe, while mobile services are running on a Java platform. SOA is the enabler, and this lowers cost."
Similarly, in the financial services industry, SOA could enable banks to process loans faster or offer speedier service with fewer hassles, he adds.
At Cigna Corp., SOA evolved differently than it did at MassMutual, but it yielded similar results. The Philadelphia-based health insurer got started with SOA around 2001, jumping into the technology wholeheartedly. While many other user organizations were testing Web services at the departmental level, Cigna rolled out SOA for large-scale, companywide systems. Deployments included new call center software and a consumer accounts management application.
"We built out the existing hardware and software infrastructure, and now there are pieces of SOA in nearly every mission-critical application," says Stephen Bergeron, senior director of architecture at Cigna.
The company relies on SOA for process orchestration, data services and business services, among other things, he says.
Cigna has rethought -- from both a business and an IT perspective -- how different business units will access and use shared applications, Bergeron explains.
Because many business applications have overlapping features, it's important to define upfront the function that each service is intended to fulfill, and to govern each one's use accordingly, Bergeron says. Doing so will ensure that technology is used appropriately. Taking that step is "especially important as SOA is adopted across the enterprise," he adds.
Today, Cigna's shared-services registry and repository promote greater data sharing. The registry contains information about which applications are integrated with the SOA, and which reusable code each uses. The repository stores the reusable code.
Expansion Strategy The use of services for mission-critical applications represents a shift. It's different from an application made up of services, or one that uses services that are separate from the SOA, Forrester's Gilpin explains.
The use of SOA typically expands in this manner: Companies first use Web services for small, one-off projects and then, as those smaller initiatives succeed, start deploying SOA across the entire enterprise.
To be successful, such an expansion needs to be accompanied by a shift in thinking about what SOA requires from a business process standpoint.
Elevating Web services from application integrators to enterprisewide SOA adds complexity, which creates challenges. These include figuring out which applications ought to consume services, and how they should do that. For this shift to occur successfully, IT managers need to ask different questions than they did during the technology's earlier days.