Systems and methods for notifying multiple hosts from an industrial controller

• US 8,150,959 B1
• Filed: 11/17/2004
• Issued: 04/03/2012
• Est. Priority Date: 11/17/2003
• Status: Active Grant

• Current Assignee: Rockwell Automation Technologies Incorporated (Allen-Bradley Co., Inc.)
• Original Assignee: Rockwell Automation Technologies Incorporated (Allen-Bradley Co., Inc.)
• Inventors: Bezdicek, Jan, Hall, Kenwood H.
• Primary Examiner(s): MACILWINEN, JOHN MOORE JAIN
• Application Number:
  US10/990,432
• Time in Patent Office: 2,694 Days
• Field of Search: 709/224, 709/203
• US Class Current: 709/224
• CPC Class Codes: G05B 23/027 Alarm generation, e.g. communication protocol; Forms of alarm

Abstract

The subject invention facilitates alert notification in an industrial environment. The systems and methods enable subscribing devices, such as hosts, to receive events and/or alarms associated with industrial controllers. In addition, a subscribed component can unsubscribe, refresh notification related information, and/or acknowledge a notification. The foregoing can be achieved through a set of objects (e.g., notify objects) that implement a notification and dynamic subscription process. A host system can instantiate an associated notify object, subscribe to an event, and be notified about the event. The invention enables multiple hosts to subscribe to the same event, allows each host to select events of interest, and enables the events to be queued if the events occur faster than can be sent. In one aspect of the invention, the systems and methods can be utilized with an event and alarm infrastructure that is applicable on a Control and Information Protocol (CIP).

Claims

1. A system that facilitates providing subscribers with associated alert notifications within an industrial environment, comprising:

a processor;

a memory communicatively coupled to the processor, the memory having stored therein computer-executable instructions configured to implement the system, including;

receiving software configured to interface with an industrial controller; and

alert management software configured to receive a command from a subscribing entity to instantiate an instance of a notify object class within the industrial controller, the instance of the notify object class having a set of class instance attributes including at least an Alert Type attribute specifying a type of Alert object to which the subscribing entity is subscribing and a Notify Timeout attribute,

wherein the instance of the notify object class is configured to receive an alert notification from the industrial controller and convey the alert notification to the subscribing entity in response to generation of the alert notification by an Alert object corresponding to the type specified by the Alert Type attribute, and

wherein the instance of the notify object class is configured to delete automatically after a connection between the subscribing entity and the instance has been closed for an amount of time specified by the Notify Timeout attribute.

2. The system of claim 1, wherein the alert management software is configured to execute within the industrial controller.

3. The system of claim 1, wherein the instance of the notify object class has a set of associated services that facilitate at least one of subscription to receive the alert notification, cancellation of a subscription the alert notification, refreshment of alert related information, or acknowledgement of the alert notification.

4. The system of claim 1, wherein the instance of the notify object class is configured to subscribe to receive the alert notification from the Alert object via a subscription object.

5. The system of claim 1, wherein the notify object class has a set of associated class attributes including at least a Revision attribute indicating a revision of object class definition and a Number of Instances attribute indicating a number of created instances of the notify object class.

6. The system of claim 1, wherein the instance of the notify object class is a Control and Information Protocol (CIP) object employed in an alert and subscription architecture, and wherein the architecture is a CIP based architecture that includes:

a CIP layer that corresponds to a specification of the CIP;

a CIP Dynamic Publisher/Subscriber Layer that defines a dynamic publisher/subscriber mechanism that allows a subscriber to register to be notified about information published by a publisher; and

a CIP Notification Layer that specifies a behavior of the alert notification.

7. A system that facilitates alert notification in connection with an industrial control system, comprising:

a processor;

a memory communicatively coupled to the processor, the memory having stored therein computer-executable instructions configured to implement the system, including;

subscription software configured to accept, from a subscribing host, a subscription to receive an alert notification that meets an alert criterion, the alert notification associated with a respective alert in an industrial controller, wherein the subscription software is further configured to invoke an instance of a notify object class defined within the industrial controller in response to acceptance of the subscription and to employ the instance of the notify object class to subscribe the subscribing host to receive the alert notification, the instance of the notify object class having a plurality of class instance attributes including at least an Alert Type attribute specifying a type of Alert object to which the subscribing host is subscribing and a Notify Timeout attribute;

interface software configured to interact with the industrial controller to receive the alert notification; and

distribution software configured to provide the alert notification to the subscribing host in response to a determination that the alert notification corresponds to the Alert object specified by the Alert Type attribute, the distribution software configured to combine multiple alert notifications into a single packet,

wherein the instance of the notify object class is configured to delete automatically after a connection between the subscribing entity and the instance of the notify object class has been closed for a predetermined amount of time, the predetermined amount of time specified by the Notify Timeout attribute.

8. The system of claim 7, wherein the distribution component is a dynamic publisher.

9. The system of claim 7, wherein the alert criterion relates to an occurrence detectable by a publisher determined to be relevant to at least one of the industrial controller or the subscribing host.

10. The system of claim 7, wherein the alert is defined in the industrial controller by at least one of a data table structure or an instruction.

11. The system of claim 7, wherein the instance of the notify object class is configured to implement an associated Unsubscribe service that allows the subscribing host to unsubscribe from receiving the alert notification.

12. The system of claim 7, wherein the instance of the notify object class is configured to implement an associated Refresh service that refreshes notification related information.

13. The system of claim 7, wherein the instance of the notify object class is configured to implement an associated Acknowledge_Alert service that acknowledges the alert notification.

14. The system of claim 7, wherein the instance of the notify object class is a Control and Information Protocol (CIP) object employed in an alert and subscription architecture, the architecture is a CIP based architecture that includes:

a CIP layer that corresponds to a specification of the CIP;

a CIP Dynamic Publisher/Subscriber Layer that defines a dynamic publisher/subscriber mechanism that allows a subscriber to register to be notified about information published by a publisher; and

a CIP Notification Layer that specifies a behavior of the alert notification.

15. A method that facilitates alert notification distribution in an industrial environment, comprising:

defining a notify object class within an industrial controller;

invoking an instance of the notify object class having a set of associated class instance attributes including at least an Alert Type attribute specifying a type of Alert object from which alert notifications are to be received, wherein the invoking the instance includes invoking an instance employed in a Control and Information Protocol (CIP) based architecture;

employing the instance of the notify object class to subscribe to receive an alert notification associated with an alert declared in the industrial controller and generated by the Alert object type specified by the Alert Type attribute; and

automatically deleting the instance of the notify object class after a connection between the instance and a subscribing entity is closed for a predetermined amount of time defined by a Notify Timeout attribute associated with the instance.

16. The method of claim 15, further comprising unsubscribing from the Alert object using an Unsubscribe service associated with the instance of the notify object class.

17. The method of claim 15, further comprising refreshing notification related information using a Refresh service associated with the instance of the notify object class.

18. The method of claim 15, further comprising acknowledging a notification using an Acknowledge_Alert service associated with the instance of the notify object class.

19. The method of claim 15, further comprising receiving the alert notification from a CIP-based architecture that includes a CIP layer that corresponds to a specification of the CIP, a CIP Dynamic Publisher/Subscriber Layer that defines a dynamic publisher/subscriber mechanism that allows a subscriber to register to be notified about information published by a publisher, and a CIP Notification Layer that specifies a behavior of the alert notification.

20. A computer-readable memory having stored thereon computer-executable instructions that, in response to execution, cause a computer to perform operations, comprising:

invoking an instance of a notify object class having a plurality of class instance attributes including at least an Alert Type attribute specifying a type of Alert object in an industrial controller from which to receive an event notification;

subscribing to receive the event notification from the specified type of Alert object via the instance of the notify object class in a system that is employed in an alert and subscription architecture;

receiving the event notification in response to generation of the event notification by an Alert object corresponding to the type specified by the Alert Type attribute; and

associating the instance of the notify object class with a notify timeout value that specifies an amount of time subsequent to disconnecting from the instance of the notify object class after which the instance of the notify object class will be automatically deleted.

21. The computer-readable memory of claim 20, wherein the alert and subscription architecture is a Control and Information Protocol (CIP) based architecture that includes a CIP layer that corresponds to a specification of the CIP, a CIP Dynamic Publisher/Subscriber Layer that defines a dynamic publisher/subscriber mechanism that allows a subscriber to register to be notified about information published by a publisher, and a CIP Notification Layer that specifies a behavior of the alert notification.