Many organizations will deploy DirectoryServices such as LDAP or UDDI to manage resources available on their network. A Client can use these services as a way to find Servers by using APIs specific to DirectoryService to query for UA Servers or UA DiscoveryServers available on the network. The Client would then use the URLs for DiscoveryEndpoints stored in the DirectoryService to request the EndpointDescriptions necessary to connect to an individual servers
Some implementations of a GlobalDiscoveryServer will be a front-end for a standard Directory Service. In these cases, the QueryApplications method will return the same information as the DirectoryService API. The discovery process for this scenario is illustrated in Figure 37.