Method and system for transmitting and receiving alarm notifications and acknowledgements within a telecommunications network

• US 6,237,034 B1
• Filed: 11/04/1997
• Issued: 05/22/2001
• Est. Priority Date: 11/04/1997
• Status: Expired due to Term

• Current Assignee: Ciena Corporation
• Original Assignee: Nortel Networks Limited (Nortel Networks Corporation)
• Inventors: Fulford, Fraser
• Primary Examiner(s): Geckil, Mehmet B.
• Assistant Examiner(s): Vaughn, Jr., William C.
• Application Number:
  US08/963,629
• Time in Patent Office: 1,295 Days
• Field of Search: 340/502, 340/506, 340/825.06, 340/825.16, 379/33, 379/34, 379/22, 379/32, 379/37, 395/180, 709/201, 709/202, 709/223, 709/224, 714/26-39, 714/48, 714/47
• US Class Current: 709/224
• CPC Class Codes: H04L 41/0604 using filtering, e.g. reduction of information by using priority, element types, position or time

Abstract

A system and method for acknowledging alarms is provided in which alarm acknowledgement information is managed in a distributed fashion by all entities interested in the alarms. In the course of an alarm acknowledgement being transmitted from an entity which generated the alarm acknowledgement back to the source of the alarm, each intervening entity records the fact that the alarm has been acknowledged, and sends notifications of this fact to other entities. In this manner, a single acknowledgement is propagated to the entire system. There is no need for a non-volatile store recording alarm acknowledgement information because the information will be present at a large number of entities any one of which can be used to update the information in a temporarily failed entity.

Claims

1. In a network comprising a plurality of AGE'"'"'s (alarm generating entity) which generates alarms and a plurality of interconnected SME'"'"'s (surveillance management entities) each AGE in direct communication with a respective one of the SME'"'"'s, for each {SME,AGE} pair a direction of communication towards the AGE being defined as upstream for that {SME,AGE} pair and a direction of communication away from the AGE being defined as downstream for that {SME,AGE} pair, a method of acknowledging alarms comprising the steps of in respect of each alarm generated by a respective AGE:

a) a particular SME generating an alarm acknowledgement to the alarm and passing this to a single SME upstream for the {particular SME, respective AGE} pair;

b) in respect of each alarm acknowledgement to the alarm received by an SME, the SME preforming the steps of;

recording the alarm acknowledgement;

forwarding the alarm acknowledgement upstream to a single SME upstream for the {SME, respective AGE} pair unless the SME is the SME in direct communication with the respective AGE in which case forwarding the alarm acknowledgement upstream to the respective AGE;

sending to all SME'"'"'s which are downstream for the {SME, respective AGE }pair which are interested in the alarm an alarm notification that an alarm acknowledgement has been sent;

c) in response to receiving an alarm notification received by an SME;

the SME recording the alarm notification; and

the SME sending an alarm notification to all SME'"'"'s which are downstream for the {SME, respective AGE} pair which are interested in the alarm.

2. A method according to claim 1 wherein each alarm has a unique alarm identifier, and each alarm acknowledgement and notification includes the alarm identifier of the alarm the acknowledgement or notification relates to.

3. A method according to claim 2 further comprising the step of each SME recording the alarm identifier of all alarms it receives.

4. A method according to claim 3 further comprising in respect of each alarm generated by a respective AGE:

the particular SME including in the alarm acknowledgement a timestamp indicating when the alarm acknowledgement was generated.

5. A method according to claim 4 wherein each notification includes the timestamp of the alarm acknowledgement from which it was originally generated.

6. A method according to claim 5 wherein the step of recording the acknowledgement comprises recording an “

Acknowledged”

state and the timestamp in association with the alarm identifier.

7. A method according to claim 6 wherein the step of recording a notification comprises recording an “

Acknowledged”

state and the time stamp in association with the alarm identifier.

8. A method according to claim 7 further comprising the steps of:

in respect of each alarm acknowledgement to the alarm received by an SME;

in response to receiving the alarm acknowledgement, before performing the three steps of recording the acknowledgement, forwarding the alarm acknowledgement and sending the notification(s), determining whether the alarm acknowledgement is correct, and if not discarding the alarm acknowledgement without performing the three steps.

9. A method according to claim 7 further comprising the steps of:

in response to receiving an alarm notification received by an SME, before the two steps of recording the alarm notification and sending alarm notification(s) determining whether the alarm notification is new, and if not discarding the alarm notification without performing the two steps.

10. A method according to claim 8 wherein determining whether the alarm acknowledgement is correct comprises determining whether there exists a timestamp previously recorded in association with the relevant alarm identifier which is earlier than that in the alarm acknowledgement, and if not concluding the alarm acknowledgement is correct.

11. A method according to claim 9 wherein determining whether an alarm notification is new comprises determining whether there exists a timestamp previously recorded in association with the relevant alarm identifier which is earlier than that in the alarm notification, and if not concluding the alarm notification is new.

12. A method according to claim 1 wherein the particular SME has a user interface, the method further comprising the steps of:

the particular SME accepting through the user interface an acknowledgement command from an operator, and generating said alarm acknowledgement.

13. A method according to claim 1 wherein a plurality of said SME'"'"'s have user interfaces, the method further comprising the step of:

each SME with a UI updating a display on the UI when an alarm notification is received to indicate that the alarm has been acknowledged.

14. A method according to claim 1 further comprising the steps of:

when an upstream SME is temporarily unreachable from a downstream SME, after connectivity is reestablished the upstream and downstream SME'"'"'s aligning their view of each alarm they are both interested in by;

if the downstream SME indicates the alarm is acknowledged and the upstream SME does not, the downstream SME sending an acknowledgement message to the to the upstream SME.

15. A method according to claim 1 further comprising the steps of:

when a downstream SME is temporarily unreachable from an upstream SME, after connectivity is reestablished the upstream and downstream SME'"'"'s coordinating their view of each alarm they are both interested in by;

if the upstream SME indicates the alarm is acknowledged and the downstream SME does not, the upstream SME sending a notification message to the downstream SME.

16. A method according to claim 15 wherein if two such acknowledgement commands are entered by two operators at two different SME'"'"'s resulting in two acknowledgement messages for the same alarm, the following steps are performed:

any SME which receives the two acknowledgement messages for the same alarm determining which acknowledgement was generated first;

if the acknowledgement which was generated first was also received first by said any SME, said any SME ignoring the second acknowledgement;

if the acknowledgement which was generated first was received second by said any SME, said any SME updating its own records and notifying every SME that it can that it has discovered the discrepancy.

17. A method according to claim 1 wherein a notification message is not sent to an SME which generated an alarm acknowledgement.

18. A method according to claim 1 wherein the recorded alarm acknowledgements and notifications are maintained in a volatile store.

19.An SME (surveillance management entity) for use in a network comprising a plurality of AGE'"'"'s (alarm generating entity) which generate alarms and an interconnected plurality of such SME'"'"'s, including each AGE in direct communication with a respective one of the SME'"'"'s, for each {SME,AGE} pair a direction of communication towards the AGE being defined as upstream for that {SME,AGE} pair and a direction of communication away from the AGE being defined as downstream for that {SME,AGE} pair, the SME comprising:

means for generating an alarm acknowledgement in response to an alarm received from a respective AGE and passing this upstream;

means for receiving and recording an alarm acknowledgement in respect of a particular alarm adapted to;

forward the alarm acknowledgement upstream to a single SME in the upstream direction for the {SME,AGE which generated the alarm} pair or in the case of the SME being the SME in direct communication with the AGE which generated the alarm forward the alarm acknowledgement upstream to the AGE, and

send downstream to all SME'"'"'s interested in the particular alarm an alarm notification that an alarm acknowledgement has been sent;

means for processing an alarm notification in respect of a particular alarm adapted to determine whether the alarm notification is new,

record the alarm notification if it is new and discard the alarm notification if it is not new, and

send the alarm notification downstream to all SME'"'"'s interested in the alarm.

19. An SME according to claim 19 wherein the means for recording the alarm acknowledgement and the means for recording the alarm notification comprise a volatile store.

20. An SME according to claim 19 further comprising a user interface for displaying alarms and alarm notifications indicating that alarms have been acknowledged.