You can aggregate data from multiple remote servers into a single DataHub instance, and bring all the data into one client.

This scenario involves configuring three OPC server machines and one OPC client machine for tunnelling. Aggregation takes place on the OPC client machine.

You can also use tunnelling to bring data from a single server to many remote clients.

This scenario involves setting up one OPC server machine and three OPC client machines for tunnelling. Aggregation takes place on the OPC server machine.

You can link multiple DataHub instances together to form a daisy chain.

The middle DataHub instance in this scenario is configured as both a tunnelling slave and a tunnelling master.

See Typical Scenarios for scenarios that let you tunnel through firewalls and DMZs, keeping all outbound firewall ports closed. That section also covers redundant tunnelling connections.