Review: ESB Suites

It's no wonder so many enterprises are looking to build out their SOAs--the agility a service-oriented architecture promises, within both IT and the business, is enticing and financially rewarding. The reuse of legacy assets, if not necessarily code, is a benefit long promised by EAI (enterprise application integration) but rarely realized. Granted, agility is one of those marketing words we try to avoid. But in this case it's warranted to describe the ability to modify business processes without code, as well as to describe the capability to modify the inner workings of a business service without affecting the clients and services that rely on the modified service. In a truly agile system, for example, a customer-lookup service can be changed to use an Oracle database from a COBOL copybook, and the client should be none the wiser.

Problem is, once you start digging, you'll find SOAs are a lot like your skeletal system: There are many moving parts, some of them essential and others--like the coccyx!--you may be able to do without. And like your skeletal system with its bones and ligaments, SOAs aren't just a single product. It's an architectural concept that must be implemented with many types of products, each designed to fulfill a purpose within the overall architecture.