RELIABLE MESSAGING INSTRUCTION

• US 20100205271A1
• Filed: 04/23/2010
• Published: 08/12/2010
• Est. Priority Date: 02/25/2005
• Status: Active Grant

• Current Assignee: Rockwell Automation Technologies Incorporated (Allen-Bradley Co., Inc.)
• Original Assignee: Rockwell Automation Technologies Incorporated (Allen-Bradley Co., Inc.)
• Inventors: Callaghan, David M.
• Granted Patent: US 8,402,101 B2
• Time in Patent Office: Days
• US Class Current: 709/206
• CPC Class Codes: G06Q 10/00 Administration; Management

Abstract

The subject invention provides reliable messaging with and within a control environment. The systems and methods utilize a message broker that facilitates message exchange. The message broker can be located within an industrial controller, as a dedicated entity within a control environment and/or an entity external to the control environment. Messages transmitted from an industrial controller and/or the external entity can be routed through the message broker prior to reaching a destination, wherein the message can be stored in the message broker and subsequently obtained by a recipient. The message broker decouples the message sender (e.g., an industrial controller, an external entity . . . ) from the message recipient (e.g., an industrial controller, an external entity . . . ) such that messages can be successfully transmitted (to the message broker) regardless of a state of the recipient, and messages can be retrieved (from the message broker) regardless of a state of the sender.

Claims

1. A system that facilitates decoupled transmission of messages between a sender and a recipient in an industrial automation environment, comprising:

at least one broker enabled to receive and store a message from at least one controller within an industrial automation system, and to deliver the message to at least one entity subscribed to receive the message in accordance with at least one notification policy specified by the at least one entity.

2. The system of claim 1, wherein the at least one broker is enabled to receive and store the message independent of a state of the at least one entity.

3. The system of claim 1, wherein the at least one notification policy includes at least an instruction to send messages relating to a data change within an industrial process to the entity if the data change is greater than a threshold value.

4. The system of claim 1, wherein the at least one notification policy includes at least a specified minimum time delay between message transmissions to the at least one entity.

5. The system of claim 1, wherein the at least one notification policy includes at least an instruction that the broker is to delete unhandled messages after a specified elapsed time.

6. The system of claim 1, wherein the broker is enabled to transmit a notification to the at least one entity upon receipt of a new message from the at least one controller, the notification informing the at least one entity that the new message is available for retrieval.

7. The system of claim 1, wherein the broker is enabled to receive and store at least one message format schema from the at least one controller for retrieval by the at least one entity, the at least one message format schema informing the at least one entity of a message format used by the at least one controller.

8. The system of claim 1, wherein the at least one broker comprises a first broker associated with the at least one controller and a second broker associated with the at least one entity, wherein notification policies are individually configurable for the first broker and the second broker.

9. The system of claim 1, wherein the broker segregates messages received from the at least one controller into two or more topics.

10. The system of claim 9, wherein the broker is enabled to process a subscription request from the at least one entity to subscribe to a subset of the two or more topics, and to deliver messages associated with the subset to the at least one entity based on the subscription request.

11. A method for decoupled delivery of messages in an industrial control environment, comprising:

receiving a message from at least one controller within an industrial automation system;

storing the message; and

delivering the message according to at least one notification policy to at least one entity subscribed to receive the message.

12. The method of claim 11, wherein the receiving comprises receiving the message independent of an availability of the at least one entity to receive the message.

13. The method of claim 11, wherein the delivering the message according to at least one notification policy comprises delivering the message if a data change being reported by the message is greater than a threshold value.

14. The method of claim 11, wherein the delivering a message according to at least one notification policy comprises deleting the message if the message remains unhandled after at least an elapsed time specified by the at least one entity.

15. The method of claim 11, further comprising transmitting a notification to the at least one entity in response to the receiving, the notification informing the at least one entity that the message is available for retrieval.

16. The method of claim 11, further comprising:

receiving at least one message format schema from the at least one controller; and

employing the at least one message format schema to inform the at least one entity of the message'"'"'s format.

17. The method of claim 11, wherein the storing comprises storing the message in one of at least two topic-specific queues based on a topic of the message.

18. The method of claim 17, further comprising:

receiving a request from the at least one entity to subscribe to a selected queue of the at least two topic-specific queues; and

delivering messages stored in the selected queue to the at least one entity upon detecting that the at least one entity is available to receive messages.

19. A system that decouples a sender and a receiver of messages in an industrial automation environment, comprising:

means for receiving a message from at least one controller within an industrial automation system;

means for storing the message; and

means for delivering the message according to at least one notification policy to at least one entity subscribed to receive the message.

20. The system of claim 19, wherein the means for receiving a message comprises means for receiving the message independent of an availability of the at least one entity to receive the message.