In many cases Clientsdo not know which Serversexist but possibly know which hosts might have Serverson them. In this situation the Clientwill look for the LocalDiscoveryServeron a host by constructing a DiscoveryUrlusing the well-known addresses defined in OPC 10000-6.

If a Clientfinds a LocalDiscoveryServerthen it will call the FindServers Serviceon the LDS to obtain a list of Servers and theirDiscoveryUrls. The Clientwould then call the GetEndpoints service for one of the Serversreturned. The discovery process for this scenario is illustrated in Figure 3.

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Figure 3– The Local Discovery Process