Patent ID: 8132042

Claim:
A method for exchanging data based on OPC communications protocol, comprising: providing at least one standby OPC server connected in parallel to a master OPC server, wherein an OPC client is connected to the master OPC server via a first communications connection and to the at least one standby OPC server via an at least second communications connection; exchanging data between the OPC client and automation devices via the first communications connection and the master OPC server, and the at least second communications connection and the at least one standby OPC server; evaluating, by the OPC client, the data coming from the master OPC server and the at least one standby OPC server; and switching over, by the OPC client, from the master OPC server to the at least one standby OPC server such that program execution is continued hitlessly at the same place, the switching over in response to the evaluating.