The discovery process is how clients lookup services that providers have published into a directory. There are many vehicles available for performing this function.

One extreme is to simply have the client hard coded to know where a service is. While this is arguably not really discovery, it is nonetheless a viable possibility in some situations. For instance, if the directory for most methods is itself a remote service, the client needs to know how to find that directory and hard coding (or placing in a parameter file) may be the only option. Still, for most service requests, hard coding should not be used as a discovery vehicle. After all, a major goal of web services is to create loose coupling, and hard coding service locations does not help.

Another possibility is that a service provider may also supply its own directory. This has the advantage of keeping the provider independent of third parties.

Finally, a directory may be given by a separate provider, perhaps even a public provider on the Internet.