Finally, the benefits of easier integration and increased agility lead to greater ROI. Buskard says he’s achieved a 200 percent return on his SOA investment. One of AXA Financial’s most popular SOA-based services is Get Client, in which any front-end app can issue a command and, after probing around the legacy systems, come back with a complete picture of a customer’s investments. Buskard says that Get Client is one example of how AXA achieves its ROI?developers design services to be generic enough that they can work with an array of front-facing systems, reducing development time and freeing developers to spend more time on business solutions. In addition, IT workers can easily incorporate new technologies into the SOA, reducing risk and expense while speeding development of new applications.

What Role Does Web Services Play in an SOA?

First, it’s important to note that an SOA does not require Web services; and Web services can be deployed without an SOA. There are those, however, who believe that building an SOA using Web services is the ideal approach. Gartner’s Thompson belongs to that camp. He cautions, however, that users must implement Web services properly to create an SOA. If done correctly, he notes, a Web service is little more than an SOA that uses SOAP and WSDL.

Buskard, on the other hand, has built his company’s SOA without Web services, as none of his internal or external customers are asking for them at this point (though he’s keeping his ear to the ground in case they do later on). Instead, he uses IBM’s WebSphere MQ as a messaging and integration layer to connect legacy systems with his front-end apps. This works in tandem with Candle’s PathWAI suite, which helps optimize WebSphere MQ by monitoring its performance.

Jon Johnson, chief engineer for Northrop Grumman Mission Systems of the Colorado Springs Engineering Organization, also has built an SOA, based on a publish-subscribe system (see "An SOA Glossary," Page 80) without Web services. He’s deployed Java Message Service as a messaging layer on top of a Web server and an application server, and uses the enterprise service bus from Sonic Software to help with integration and data movement. Johnson says that his services are designed like Web services, only without the Web services interface.

One of the major benefits of the SOA, he says, is that the right data gets sent to the right person or application. For example, when a user logs on using an ID, the system knows who the user is and pushes only the data?for example, maps and task lists?that the person is authorized to see.