There are two general modes of Server Redundancy, transparent and non-transparent.

In transparent Redundancythe Failoverof Serverresponsibilities from one Serverto another is transparent to the Client. The Clientis unaware that a Failoverhas occurred and the Clienthas no control over the Failoverbehaviour. Furthermore, the Clientdoes not need to perform any actions to continue to send or receive data.

In non-transparent Redundancythe Failoverfrom one Serverto another and actions to continue to send or receive data are performed by the Client. The Clientshall be aware of the Redundant Server Setand shall perform the required actions to benefit from the Server Redundancy.

The ServerRedundancy Objectdefined in OPC 10000-5indicates the mode supported by the Server. The ServerRedundancyType ObjectTypeand its subtypes TransparentRedundancyType andNonTransparentRedundancyType defined in OPC 10000-5specify information for the supported Redundancymode.