Patent ID: 7720639

Claim:
A communication method for communicating between a first Programmable Logic Controller and at least one of a second Programmable Logic Controller and a central unit, said method comprising: transmitting, by the first Programmable Logic Controller to at least one of the second Programmable Logic Controller and the central unit, a file containing at least one of a description of information contained in a set of data items and a communication sequence of the set of data items, wherein the file is transmitted via a first communication channel; communicating the set of data items between the first Programmable Logic Controller and at least one of the second Programmable Logic Controller and the central unit via a second communication channel separate from the first communication channel, according to an essentially deterministic transfer structure; and controlling, by a monitoring unit, operation of a remote monitored unit based on the set of data items and the file, wherein the remote monitored unit including the first Programmable Logic Controller, the second Programmable Logic Controller, and the central unit, and the monitoring unit monitors the remote monitored unit.