SYSTEM AND METHOD FOR ANALYZING AND TESTING PACKET FLOWS TO LOCALIZE PROBLEMS

• US 20110211459A1
• Filed: 06/30/2010
• Published: 09/01/2011
• Est. Priority Date: 03/01/2010
• Status: Active Grant

• Current Assignee: Arlington Technologies, LLC (Dominion Harbor Enterprises, LLC)
• Original Assignee: Avaya Incorporated
• Inventors: MELOCHE, Jean
• Granted Patent: US 8,457,004 B2
• Time in Patent Office: Days
• US Class Current: 370/245
• CPC Class Codes: H04L 41/5025 by proactively reacting to service quality change, e.g. by reconfiguration after service quality degradation or upgrade
• CPC Class Codes: H04L 41/5087 wherein the managed service relates to voice services management of VoIP services H04M7/0081
• CPC Class Codes: H04L 43/0835 One way packet loss
• CPC Class Codes: H04L 43/087 Jitter
• CPC Class Codes: H04L 43/0894 Packet rate
• CPC Class Codes: H04L 43/16 Threshold monitoring
• CPC Class Codes: H04L 47/10 Flow control; Congestion control
• CPC Class Codes: H04L 47/12 Avoiding congestion; Recovering from congestion
• CPC Class Codes: H04L 47/2416 Real-time traffic
• CPC Class Codes: H04L 47/2458 Modification of priorities while in transit
• CPC Class Codes: H04L 47/31 by tagging of packets, e.g. using discard eligibility [DE] bits
• CPC Class Codes: H04L 65/104 in the network
• CPC Class Codes: H04L 65/611 for multicast or broadcast systems for broadcast or conference H04L12/18; arrangements for broadcast or distribution combined with broadcast H04H20/00; arrangements for broadcast applications with a direct linkage to broadcast information or to broadcast space-time H04H60/00; selective distribution of broadcast services, e.g. multimedia broadcast multicast service [MBMS], H04W4/06

Abstract

Disclosed herein are systems, methods, and computer-readable storage media for analyzing packet flows and generating an alarm and for active testing of a network to localize problems. The system analyzes packet flows for bitstreams associated with a network node in order to compute a measure of protection that a queue of the network node gives to a high-priority one of the bitstreams relative to a low-priority one of the bitstreams, and uses the measure of protection to determine whether the network node is a source of a protection error with respect to priority markings for packets flowing through the network node, and generates an alarm upon determining that the network node is a source of a protection error with respect to the priority markings for the packets flowing through the network node.

Claims

1. A method of managing a packet network, the method comprising a data processor executing computer instructions stored on a non-transitory computer-readable storage medium to perform the steps of:

(a) analyzing packet flows for bitstreams associated with a network node in order to compute a measure of protection that a queue of the network node gives to a high-priority one of the bitstreams relative to a low-priority one of the bitstreams;

(b) using the measure of protection to determine whether the network node is a source of a protection error with respect to priority markings for packets flowing through the network node; and

(c) generating an alarm upon determining in step (b) that the network node is the source of the protection error with respect to the priority markings for the packets flowing though the network node.

2. The method as claimed in claim 1, wherein the high-priority one of the bitstreams is an audio bitstream, and the low-priority one of the bitstreams is one of a video bitstream and a data bitstream, and the protection error is an error of the network node failing to give packets of the audio bitstream priority over packets of the video bitstream or packets of the data bitstream.

3. The method as claimed in claim 1, wherein the network node is one of a provider edge (PE) router transmitting the bitstreams to a customer edge (CE) router and the customer edge (CE) router transmitting the bitstreams to the provider edge (PE) router.

4. The method as claimed in claim 3, further comprising:

computing a matrix of protection values for respective bit streams between a plurality of customer edge (CE) routers and passing through a plurality of provider edge (PE) routers; and

inspecting one of a row and a column of the matrix to find one of a lack of protection from a single source to multiple destinations indicating that one of the plurality of customer edge (CE) routers is the source of the protection error, and a lack of protection from multiple sources to a single destination indicating that one of the plurality of provider edge (PE) routers is the source of the protection error.

5. The method as claimed in claim 1, wherein analyzing packet flows further comprises correlating jitter of packets of the low-priority one of the bitstreams with jitter of packets of the high-priority one of the bitstreams over time to compute the measure of protection.

6. The method as claimed in claim 1, further comprising generating pseudopackets marked as low-priority packets and transmitting the pseudopackets through the network node so that there is significant temporal variation in jitter of the packets of the low-priority one of the bitstreams over time.

7. The method as claimed in claim 1, wherein using the measure of protection to determine whether the network node is the source of a protection error further comprises computing a temporal variation in jitter of the packets of the low-priority one of the bitstreams over time, and determining that the network node is the source of the protection error with respect to priority markings for packets flowing through the network node upon finding that the temporal variation indicates significant temporal variation and the measure of protection indicates a failure of the network node to give packets of the high-priority one of the bitstreams priority over packets of the low-priority one of the bitstreams.

8. A system for managing a packet network, the system comprising:

a data processor; and

a non-transitory computer-readable storage medium storing computer instructions that, when executed by the data processor, perform the steps of;

(a) analyzing packet flows for bitstreams associated with a network node in order to compute a measure of protection that a queue of the network node gives to a high-priority one of the bitstreams relative to a low-priority one of the bitstreams;

(b) using the measure of protection to determine whether the network node is a source of a protection error with respect to priority markings for packets flowing through the network node; and

(c) generating an alarm upon determining in step (b) that the network node is the source of the protection error with respect to the priority markings for the packets flowing though the network node.

9. The system, as claimed in claim 8, wherein the high-priority one of the bitstreams is an audio bitstream, and the low-priority one of the bitstreams is one of a video bitstream and a data bitstream, and the protection error is an error of the network node failing to give packets of the audio bitstream priority over packets of the video bitstream or packets of the data bitstream.

10. The system as claimed in claim 8, wherein the network node is one of a provider edge (PE) router transmitting the bitstreams to a customer edge (CE) router, and the customer edge (CE) router transmitting the bitstreams to the provider edge (PE) router.

11. The system as claimed in claim 10, wherein the computer instructions, when executed by the data processor, further perform the steps of

computing a matrix of protection values for respective bit streams between a plurality of customer edge (CE) routers and passing through a plurality of provider edge (PE) routers, and

inspecting one of a row and a column of the matrix to find one of a lack of protection from a single source to multiple destinations indicating that one of the plurality of customer edge (CE) routers is the source of the protection error, and a lack of protection from multiple sources to a single destination indicating that one of the plurality of provider edge (PE) routers is the source of the protection error.

12. The system as claimed in claim 8, wherein analyzing packet flows further comprises correlating jitter of packets of the low-priority one of the bitstreams with jitter of packets of the high-priority one of the bitstreams over time to compute the measure of protection.

13. The system as claimed in claim 8, wherein the computer instructions, when executed by the data processor, further generate pseudopackets marked as low-priority packets and transmit the pseudopackets through the network node so that there is significant temporal variation in jitter of the packets of the low-priority one of the bitstreams over time.

14. The system as claimed in claim 8, wherein using the measure of protection to determine whether the network node is a source of a protection error further comprises computing a temporal variation in jitter of the packets of the low-priority one of the bitstreams over time, and determining that the network node is a source of a protection error with respect to priority markings for packets flowing through the network node upon finding that the temporal variation indicates significant temporal variation and the measure of protection indicates a failure of the network node to give packets of the high-priority one of the bitstreams priority over packets of the low-priority one of the bitstreams.

15. A non-transitory computer-readable storage medium storing computer instructions that, when executed by a data processor, perform management of a packet network by the steps of:

(a) analyzing packet flows for bitstreams associated with a network node in order to compute a measure of protection that a queue of the network node gives to a high-priority one of the bitstreams relative to a low-priority one of the bitstreams;

(b) using the measure of protection to determine whether the network node is a source of a protection error with respect to priority markings for packets flowing through the network node; and

(c) generating an alarm upon determining in step (b) that the network node is the source of the protection error with respect to the priority markings for the packets flowing though the network node.

16. The non-transitory computer-readable storage medium as claimed in claim 15, wherein the high-priority one of the bitstreams is an audio bitstream, and the low-priority one of the bitstreams is one of a video bitstream and a data bitstream, and the protection error is an error of the network node failing to give packets of the audio bitstream priority over packets of the video bitstream or packets of the data bitstream.

17. The non-transitory computer-readable storage medium as claimed in claim 15, wherein the network node is one of a provider edge (PE) router transmitting the bitstreams to a customer edge (CE) router, and a customer edge (CE) router transmitting the bitstreams to a provider edge (PE) router, and the computer instructions, when executed by the data processor, perform the steps of

computing a matrix of protection values for respective bit streams between a plurality of customer edge (CE) routers and passing through a plurality of provider edge (PE) routers, and

inspecting one of a row and a column of the matrix to find one of a lack of protection from a single source to multiple destinations indicating that one of the plurality of customer edge (CE) routers is a source of a protection error, and a lack of protection from multiple sources to a single destination indicating that one of the plurality of provider edge (PE) routers is the source of the protection error.

18. The non-transitory computer-readable storage medium as claimed in claim 15, wherein analyzing packet flows further comprises correlating jitter of packets of the low-priority one of the bitstreams with jitter of packets of the high-priority one of the bitstreams over time to compute the measure of protection.

19. The non-transitory computer-readable storage medium as claimed in claim 15, wherein the computer instructions, when executed by the data processor, further perform the steps of generating pseudopackets marked as low-priority packets, and transmitting the pseudopackets through the network node so that there is significant temporal variation in jitter of the packets of the low-priority one of the bitstreams over time.

20. The non-transitory computer-readable storage medium as claimed in claim 15, wherein the step of using the measure of protection to determine that the network node is a source of a protection error with respect to priority markings for packets flowing through the network node includes computing a measure of temporal variation in jitter of the packets of the low-priority one of the bitstreams over time, and determining that the network node is the source of the protection error with respect to priority markings for packets flowing through the network node upon finding that the measure of temporal variation indicates significant temporal variation, and the measure of protection indicates a failure of the network node to give packets of the high-priority one of the bitstreams priority over packets of the low-priority one of the bitstreams.