Enterprise SOA

What challenges do companies face in adopting ESA?

The biggest challenge any enterprise faces in moving to ESA is the past—the enterprise's own past, that is. This past often weighs down the present in the quite tangible form of legacy applications and layers of IT infrastructure. Due to various mergers and acquisitions, not to mention the decentralized IT purchasing that may have taken place in years past—departmental computing, data marts, and so forth—it's not uncommon for today's large corporation to find itself running a dozen Enterprise Resources Planning (ERP) systems, and perhaps at least that many Customer Relationship Management (CRM) systems. Generally, such corporations conceived, designed, and implemented these systems without the slightest knowledge or forethought of web services, enterprise services, or composite applications. Yet that doesn't mean they must be excluded from the new service-oriented IT landscape. It just takes a little extra thinking to meld them into a new architecture that's based on enterprise services.

The move from old to new—from understanding and managing IT as a collection of isolated, stovepipe applications, each one a realm unto itself, to running IT as an array of service components that can be snapped together like so many building blocks—cannot be achieved overnight. It requires careful and methodical planning.

There is another problem, too. Many people involved in IT for several years now have recognized the great potential of web services. ...