Not all services are created equal. It would be great if implementing SOA were simply a matter of applying a standard design pattern to all services. Once IT had identified and codified an optimal design standard, services could be stamped out in assembly-line fashion until the IT landscape had been transformed. Unfortunately, we don’t live in a cookie-cutter service Utopia.

Different Strokes for Different Folks
Services exist in all shapes, sizes, colors, and flavors. What’s more, they’re not all conducive to the same design approaches. Services are the modern digital incarnation of useful business functions: Get Employee, Create Purchase Order, Calculate Credit Score, Find Recommended Products. Any amount of work done by a system on behalf of another system (or user) qualifies as a business function. IT’s raison d’etre is to provide these functions to the enterprise, and the types of functions offered are as varied as the customers who use them, the complexity of the tasks done, and how each one relates to other functions. Some functions are big, some are small, some are used throughout the enterprise, and some are used only in obscure business niches. No two services are exactly alike and each service delivers a unique amount of value to the enterprise. To understand a service’s value we need to understand how it’s used.

Like books, songs, movies, news, and coffee, different customers prefer different IT services. There are popular “mainstream” services that appeal to large groups and unpopular “niche” services that appeal to only a few people. What’s more, as the world is discovering that there’s tremendous value in offering niche products to obscure “Long-Tail” consumer markets, IT has a similar opportunity in providing big value to the enterprise by offering Long Tail services. This flies in the face of traditional IT strategy (and popular SOA strategy for that matter), but it’s an essential ingredient in the recipe for agility.