Method and apparatus for outage measurement

• US 7,523,355 B2
• Filed: 09/25/2006
• Issued: 04/21/2009
• Est. Priority Date: 07/30/2002
• Status: Expired due to Term

• Current Assignee: Cisco Technology, Inc. (Cisco Systems, Inc.)
• Original Assignee: Cisco Technology, Inc. (Cisco Systems, Inc.)
• Inventors: Huang, Jiandong, Marathe, Madhav, Song, Sejun
• Primary Examiner(s): McCarthy; Christopher S
• Application Number:
  US11/534,908
• Publication Number:
  US 20070028147A1
• Time in Patent Office: 939 Days
• Field of Search: 714/4, 714/43, 714/47
• US Class Current: 714/43
• CPC Class Codes: H04L 41/0213 Standardised network management protocols, e.g. simple network management protocol [SNMP]
• CPC Class Codes: H04L 41/044 comprising hierarchical management structures
• CPC Class Codes: H04L 41/0604 using filtering, e.g. reduction of information by using priority, element types, position or time
• CPC Class Codes: H04L 41/064 involving time analysis
• CPC Class Codes: H04L 43/0811 by checking connectivity
• CPC Class Codes: H04L 43/10 Active monitoring, e.g. heartbeat, ping or trace-route
• CPC Class Codes: H04L 43/106 using time related information in packets, e.g. by adding timestamps

Abstract

An Outage Measurement System (OMS) monitors and measures outage data at a network processing device. The outage data can be stored in the device and transferred to a Network Management System (NMS) or other correlation tool for deriving outage information. The OMS automates the outage measurement process and is more accurate, efficient and cost effective than previous outage measurement systems.

Claims

1. An apparatus, comprising:

one or more processors;

a memory coupled to the processors comprising instructions executable by the processors, the processors operable when executing the instructions to;

monitor for outages occurring locally at a network device that forwards communications sent from one or more remote endpoints located in a first network through the network device, to a second different network;

monitor for outages occurring remotely on first network links located in the first network;

identify outage information according to the local and remote monitoring;

send the outage information from the network device, over the second network to a remote system that is located outside the first network and that monitors for outages located on second network links that are located outside the first network;

generate time stamp values according to a configured period;

store the periodically generated time stamp values in a local storage;

when recovering from a local crash, compare a most recently stored time stamp value to a local current system time to determine an outage measurement for the local crash; and

include the outage measurement within the outage information.

2. The apparatus of claim 1, wherein the processors are located in the network device, and the network device is a single point-of-failure for messages originating in the first network and addressed to other endpoints located outside the first network.

3. The apparatus of claim 2, wherein the processors are further operable to filter a plurality of failures associated with a same element into a single root cause notification that is included in the outage information.

4. The apparatus of claim 2, wherein the processors are further operable to generate connectivity measurements and component operability measurements, the connectivity measurements and the component operability measurements for inclusion within the outage information.

5. The apparatus of claim 2 wherein the processors are further operable to perform the local and the remote outage monitoring according to configuration parameters sent from the remote system.

6. The apparatus of claim 5 wherein the received configuration parameters specify a pinging rate for pings sent from the network device.

7. The apparatus of claim 5 wherein the processors are further operable to identify neighboring devices using Cisco Discovery Protocol (CDP).

8. An apparatus comprising:

one or more processors;

a memory coupled to the processors comprising instructions executable by the processors, the processors operable when executing the instructions to;

exchange communications with a remote network device that forwards messages generated by one or more remote endpoints located in a first network through the remote network device and to a second different network;

receive outage information generated by the remote network device, the received outage information corresponding to the remote network device and to first network links located in the first network;

compare the received outage information to local outage information that corresponds to second different network links that are located outside the first network, the local outage information generated independently from monitoring performed by the remote network device;

identify failures on the first network links, the remote network device and the second different network links according to the comparison; and

calculate a product of an accumulated outage time value that is included in the received outage information and an inverse of an accumulated number of failures that is included in the received outage information.

9. The apparatus of claim 8 wherein the remote network device is a single point of failure for the remote endpoints such that the processors that are located outside the first network cannot access the remote endpoints independently of the remote network device.

10. The apparatus of claim 8 wherein the processors are operable to calculate object availability using accumulated outage time values included in the received outage information.

11. The apparatus of claim 8 wherein the remote network device is a router or a switch.

12. The apparatus of claim 8 wherein the processors are further operable to send a communication to control pinging by the remote network device for generating the outage information.

13. The apparatus of claim 8 wherein the processors are further operable to output a mean time to repair.

14. An apparatus, comprising:

one or more processors;

a memory coupled to the processors comprising instructions executable by the processors, the processors operable when executing the instructions to;

monitor for outages occurring locally at a network device that is configured to forward communications sent over a first network by remote endpoints to a second network;

analyze an input rate, an output rate, an input queue packet drop and an output queue packet drop to identify at least one candidate remote endpoint for pinging, wherein the identified candidate remote endpoints are a subset of the remote endpoints;

ping the identified candidate endpoints to identify remote endpoints having outages;

identify first outage information according to the local and remote monitoring; and

send the first outage information from the network device to a remote system that is located outside the first network for combining with remotely-generated second outage information that identifies outages occurring between the network device and the remote system.

15. The apparatus of claim 14 wherein the first outage information, when combined with the second outage information, defines a completely monitored connection path extending from the remote endpoints, through the network device and to the remote system.

16. The apparatus of claim 14 wherein the processors are further operable to:

perform local monitoring by checking layer-2 link status for the network device; and

perform remote monitoring by checking layer-3 traffic flows between the remote endpoints and the network device.

17. The apparatus of claim 14 wherein the processors are further operable to monitor a software process responsive to a configuration signal sent from the remote system.

18. The apparatus of claim 14 wherein the processors select objects for remote monitoring according to configuration signals sent from the remote system.

19. An apparatus, comprising:

one or more processors;

a memory coupled to the processors comprising instructions executable by the processors, the processors operable when executing the instructions to;

identify a remote network device that is a single point of failure for an endpoint in a first network, the identified remote network device being a single point of exit for communications that are generated by the endpoint and addressed to a destination located outside the first network;

exchange command communications with the identified remote network device, the command communications to control monitoring by the remote network device of first objects located in the first network, said monitoring by the remote network device including sending pings from the remote network device to the first objects;

receive outage information generated by the remote network device according to the exchanged command communications;

monitor second objects located outside the first network, said monitoring of the second objects including sending pings from the apparatus to the second objects, and locally generate outage information according to the monitoring of the second objects; and

output a failure indication based on both the received outage information and the generated outage information, the failure indication identifying whether any communication disruptions affecting the endpoint correspond to failure of hardware operating outside the first network;

wherein the received outage information, when combined with the locally generated outage information, monitors an entire communication path extending from the endpoint located in the first network, through the network device and to the apparatus,

wherein the command communications control a start time for the monitoring by the remote network device.

20. The apparatus of claim 19 wherein the command communications control which ones of the objects in the first network are monitored by the remote network device.

21. The apparatus of claim 20 wherein the command communications control when the remote network device uses device discovery to maintain a listing of the first objects.