Redundancy in process control system

A process control system comprising at least one client device, at least one data source and at least one server device providing data transfer between the at least one client device and the at least one data source, wherein at least two parallel logical connections can be arranged for one client device of the at least one client device for transferring the same data in parallel from one data source of the at least one data source,

• the one client device is configured to check property information on parallel data units transferred by the parallel logical connections, the one client device being provided with predetermined order criteria for the property information,
• the one client device is configured to compare property information on the parallel data units transferred by the parallel logical connections to obtain comparison results,
• the one client device is configured to select data units, based on the comparison results, delivered via the parallel logical connections, having, according to the predetermined order criteria, the best property information for the use of one or more applications processing the data units,
• the parallel logical connections between the one client device and one server device of the at least one server device are arranged according to an OPC standard {OLE (Object Linking and Embedding) for Process Control}, and
• for each comparing, the one client device selects a single data unit, having the best property information, from among the parallel data units, and disregards other data units from among the parallel data units.

A device of a process control system, comprising a client device functionality for communicating with at least one server device providing data transfer in the process control system between the device and at least one data source, wherein the device is configured to set up at least two parallel logical connections for transferring the same data in parallel from one data source of the at least one data source,

• the device is configured to check property information on parallel data units received by the parallel logical connections, the device being provided with predetermined order criteria for the property information,
• the device is configured to compare property information on the parallel data units transferred by the parallel logical connections to obtain comparison results,
• the device is configured to select data units, based on the comparison results, delivered via the parallel logical connections, having, according to the predetermined order criteria, the best property information for the use of one or more applications processing the data units, and the parallel logical connections between the device and one server device of the at least one server device are arranged according to an OPC standard {OLE (Object Linking and Embedding) for Process Control}, and
• for each comparing, the device selects a single data unit, having the best property information, from among the parallel data units, and disregards other data units from among the parallel data units.

A non-transitory computer readable medium storing a computer program for controlling at least one device of a process control system, wherein the computer program controls the at least one device to:

• arrange at least two parallel logical connections for transferring the same data in parallel between one data source of at least one data source and one device of the at least one device via one server device of at least one server device,
• check property information on parallel data units transferred by the parallel logical connections,
• compare property information on the parallel data units transferred by the parallel logical connections to obtain comparison results,
• select the data units, based on the comparison results, having, according to predetermined order criteria, the best property information for the use of one or more applications processing the parallel data units, wherein the parallel logical connections between the one device and the one server device are arranged according to an OPC standard {(OLE (Object Linking and Embedding) for Process Control}, and
• for each compare step, the select step selects a single data unit, having the best property information, from among the parallel data units, and disregards other data units from among the parallel data units.