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

Aggregation takes place on the OPC client machine.

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

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.