Patent ID: 8509081

Claim:
A method of selecting paths in a process control and/or automation network, the process control and/or automation network including one or more wireless end devices for transmitting data and/or receiving data, and either one or more wireless intermediate devices for transmitting data and/or receiving data and routing received data and one or more wireless gateway devices for assigning data paths, transmitting data, receiving data and routing received data, or one or more wireless intermediate devices or one or more wireless gateway devices, wherein a source-destination pair includes links between the one or more wireless end devices, and the one or more wireless intermediate devices and/or the one or more wireless gateway devices, the method of selecting paths comprising: a. specifying a minimum reliability requirement for a selected source-destination pair; b. specifying a minimum number of paths between the selected source-destination pair; c. determining possible paths between the selected source-destination pair; d. calculating the reliability of each of the possible paths, or an effective reliability of one or more groups of possible paths; e. identifying one or more reliable paths, or one or more reliable groups of paths, by comparing the reliability of each of the possible paths or groups of possible paths with the specified minimum reliability requirements; and f. assigning the minimum number of paths for the selected source-destination pair to a routing table from the identified reliable paths or the identified reliable group of paths, and discarding, or assigning as alternate paths to the routing table, identified reliable paths or identified reliable groups of paths that exceed the minimum number of paths; wherein the wireless process control and/or automation network includes plural of the wireless intermediate devices grouped into intermediate field network sets and/or plural of the wireless gateway devices grouped into gateway field network sets, further wherein step (c) includes determining possible paths between a source-destination pair passing through a designated anchor packet selection device of a predetermined number of the field network sets, and wherein the anchor packet selection device of each field network set further includes a processor and a packet selection module executable by the processor to select a packet among plural packets of the same information with the highest quality for retransmission to the next tier.