3.1 Terms and definitions

For the purposes of this document, the terms and definitions given in OPC 10000-1, OPC 10000-2, OPC 10000-3, and the following apply.

3.1.1 Active Server

Server which is currently sourcing information

3.1.2 Deadband

permitted range for value changes that will not trigger a data change Notification

3.1.3 DiscoveryEndpoint

Endpoint that allows Clients access to Discovery Services without security

3.1.4 Endpoint

physical address available on a network that allows Clients to access one or more Services provided by a Server

3.1.5 EphemeralKey

public-private key pair generated for each execution of a key establishment process.

3.1.6 Failed Server

Server that is not operational.

3.1.7 Failover

act of switching the source or target of information.

3.1.8 Gateway Server

Server that acts as an intermediary for one or more Servers

3.1.9 HostName

unique identifier for a machine on a network

3.1.10 Redundancy

presence of duplicate components enabling the continued operation after a failure of an OPC UA component

3.1.11 RedundantServerSet

two or more Servers that are redundant with each other

3.1.12 SecurityToken

identifier for a cryptographic key set

3.1.13 ServerUri

ApplicationUri for a Server

3.1.14 SoftwareCertificate

digital certificate for a software product that can be installed on several hosts to describe the capabilities of the software product