With the advent of Web services, most enterprises that I deal with now have thousands sometimes tens of thousands of services under management. To make matters even more complex, we also have to consider services that are out of our direct control, those found on the open Internet (public services). Clearly, you can count on the number of these services increasing over time, perhaps very quickly over the next few years.

While we do have some interface information about these services, as defined by standards such as WSDL and UDDI, we really need a more complete set of info surrounding the services in order to create a proper SOA. This information should include things such as; the purpose, interfaces, parameters, rules, logic, owner, semantics, included services, and other important data. Let's call this what it is, a service descriptions.

I believe that before understanding the need for service descriptions, we need to first better understand what's information is already available within existing standards such as WSDL and UDDI.