Exclusive Focus on Web Services May Blur SOA Vision

by Robert Morris
February 1, 2006

Mainframe systems have been the backbone of most enterprises for decades. Companies are now looking to Service-Oriented Architecture (SOA) to enable consistent reuse of applications and data without requiring the consumers of those resources to understand the mainframe. Unfortunately, the focus has been primarily on the mechanics of Web Services (e.g., SOAP, WSDL, XML, HTTP), and not on identifying and meeting the real requirements to deliver SOA benefits.

There’s no shortage of vendors willing to further confuse the issue by offering simplistic solutions to delivering mainframe Web Services, and claiming this is synonymous with delivering SOA. This approach should come with a warning label: “Web Service enclosed. All assembly required.” It’s like delivering a load of lumber to a prospective home-builder. Oh, sure, everything you need to frame the house is there—except a blueprint and a basic plan for how all the pieces fit together. Once you move past the high-level marketing messages—“ Instant house—just add nails!”, you start to realize that delivering mainframe SOA is much more than just delivering mainframe components dressed up as Web Services.

It requires:

• An in-depth understanding of how the components work together to comprise a recognizable business task
• Automating the interaction of the underlying functionality and data sources necessary for the task
• The whole thing be packaged in an easily recognizable and accessible form for effective use and reuse.

 

The assembly of such right-sized services into a standardized, enterprisewide framework for the effective use of an entire company’s information and systems ensures the realization of a true SOA—all of which is why an exclusive focus on Web Services is shortsighted. So, how can organizations cut through the hype and get to a clear, deliverable SOA vision? The following three guidelines may be helpful.

 

1. Think “business services”: There’s a common misconception today that Web Services are necessarily required for—or even synonymous with—implementing an SOA. But talking “Web Services” instead of “business services” really misses the point. Web Services are likely to be a part of an SOA, but only as one of several technology options for standardizing access to services across the enterprise. The business services that comprise an SOA perform a more complex role than simply enabling the invocation of a function in a standard way. Besides being functions that are readily recognizable and understandable, they typically contain multi-step, multi-operation functionality, orchestrated within the service, with transparent communications and data transformation. Critical to successful SOA is the ability to understand and deliver such business services at the optimal level of granularity to facilitate reuse and to insulate the user from downstream maintenance. Otherwise, everything developed in support of the SOA simply becomes an elementary building block that will have to be assembled into a usable structure elsewhere, with all the attendant development, testing, and maintenance ramifications that implies.