Another important element of an SOA is a service registry. The registry is where you can login and take inventory of what services are available, etc. If an organization has to manage hundreds, maybe even thousands of web services, a functioning service registry is a critical element.
When organizations are just starting out, they might overlook the importance of a service registry. It would be best to implement one as soon as possible.
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service registry [ April 18, 2008: Message edited by: James Clark ]