Fisher-rosemount Systems, Inc

William E Bennett

Ken J Beoughter

Robert Burke Havekost

John R Shepard

Dwight D Jennings

Anthony Amaro, Jr

Michael George Ott

Dirk Thiele

Brandon Hieb

Robert G Halgren, Iii

Michael D Apel

Steve Dienstbier

Joel Nicholas Ohmart

Marina Sokolova

Jacob B Peschansky

Vinaya S Rayapeta

Brian M Capoccia

A communications network security system includes a robustness agent that operates within a communications interface of a device at one or more nodes of the network to analyze and filter messages coming from or going onto the network. At each of the nodes, the robustness agent determines one or more sets of message characteristics associated with each of the messages passing through the agent, and the agent is configured to allow certain types of messages (e.g., messages with certain predetermined sets of characteristics) to be passed through the agent, prevent messages with other predetermined characteristics from being passed through the agent, such as by halting (discarding or filtering) these messages, and/or passes still other messages having other sets of message characteristics to a volume filter to be counted. The volume filter counts the number of messages with a particular set of message characteristics and passes these messages if the number of these detected messages over a particular period of time is less than a particular threshold, and filters these messages if the number of counted messages is greater than a particular threshold over a particular period of time.

Configurable robustness agent in a plant security system

An enhanced modular controller is disclosed that includes a plurality of configurable communication ports and a control logic layer operable to control equipment of a process plant. The plurality of communication ports include a first set of communication ports and a second set of communication ports which are operable to communicate with one or more nodes of a distributed control system of the process plant. The enhanced modular controller also includes a software layer that accepts port configuration parameters that define one or more port communication rules for the first set of communication ports and for the second set of communication ports. The one or more port communication rules causes the software layer to selectively allow or restrict retransmission of incoming messages, where the incoming messages are received at the first set of communication ports or the second set of communication ports.

Systems and methods for enhanced modular controller port to port communication

Methods and apparatus to provide redundancy in a process control system are disclosed. An example method includes receiving, at a first network host, first integrity messages transmitted from a second network host over a first network. The method includes detecting a network failure over a first communication path between a first network interface of the first network host and a second network interface of the second network host via first network when a first network interface of the first network host fails to receive one of the first integrity messages expected from a first network interface of the second network host. The method includes automatically establishing a second communication path between the first network host and the second network host in response to the detected network failure.

Methods and apparatus to provide redundancy in a process control system

A communication technique enables the efficient transmission of data through a low bandwidth and/or time delayed communication link and minimizes the idle time of the communication link by using a deferred acknowledgment of message bundles to temporally pack the communication link. The transmitting system stores messages to be transmitted in a pending message queue and applies a dynamic window to the pending message queue to define a message bundle to be sent through the slow communication link. The transmitting system requests an acknowledgment for at least one message within the bundle, but does not require an acknowledgment for every message within the bundle. Transmitted messages are temporarily stored as outstanding messages in a retransmission queue until the transmitted messages are acknowledged or until a time-out period associated with the messages has lapsed. When the transmitting station receives a timely acknowledgment in response to a requested acknowledgment, the transmitting station removes all outstanding messages associated with that acknowledgment from the retransmission queue.

Deferred acknowledgment communications and alarm management

A sequence of events detection system for use in a process control system uses sequence of events detection cards to detect and store indications of events and the times at which these events take place within the process control network. The sequence of events reporting system includes a stable master time source that is used to periodically time synchronize secondary clocks within each of the nodes of the process control system. Free running counters are located within each of the sequence of events detection cards at each node and these free running counters are used to mark each event with a counter value when the sequence of events detection card first detects the event. Indications of the event and of the counter value associated with a detected event are sent from each of the sequence1 of events detection cards to a corresponding controller which uses its secondary clock, a further free running counter and the value of the sequence of events counter assigned to the event to ascertain the actual or absolute time that the event was detected at the sequence of events card. The event and the absolute time for that event is then sent to a sequence of events reporting database, where this information is stored to form a system wide sequence of events log.

Sequence of events detection in a process control system

Growing community of inventors

Georgetown, TX, United States of America

William E Bennett