Hardware percentile latency measurement

• US 10,243,842 B2
• Filed: 10/27/2017
• Issued: 03/26/2019
• Est. Priority Date: 11/05/2013
• Status: Active Grant

• Current Assignee: Cisco Technology, Inc. (Cisco Systems, Inc.)
• Original Assignee: Cisco Technology, Inc. (Cisco Systems, Inc.)
• Inventors: Chu, Kit Chiu, Hill, Jeff, Edsall, Thomas J., Alizadeh Attar, Mohammadreza
• Primary Examiner(s): Hsu, Alpus
• Assistant Examiner(s): Thai, Camquyen
• Application Number:
  US15/795,541
• Publication Number:
  US 20180069783A1
• Time in Patent Office: 515 Days
• Field of Search: None
• CPC Class Codes: H04L 12/18 for broadcast or conference , e.g. multicast
• CPC Class Codes: H04L 12/4633 Interconnection of networks using encapsulation techniques, e.g. tunneling
• CPC Class Codes: H04L 12/4641 Virtual LANs, VLANs, e.g. virtual private networks [VPN] LAN interconnection over a bridge based backbone H04L12/462; encapsulation techniques H04L12/4633; routing of packets H04L45/00; packet switches H04L49/00; virtual private networks for security H04L63/0272
• CPC Class Codes: H04L 12/4645 Details on frame tagging routing of packets H04L45/00; support for virtual LAN H04L49/354
• CPC Class Codes: H04L 2212/00 Encapsulation of packets
• CPC Class Codes: H04L 41/0654 using network fault recovery ring fault isolation or reconfiguration in loop networks without recovery actions by a network management system H04L12/437
• CPC Class Codes: H04L 43/0811 by checking connectivity
• CPC Class Codes: H04L 43/0852 Delays
• CPC Class Codes: H04L 43/0894 Packet rate
• CPC Class Codes: H04L 43/16 Threshold monitoring
• CPC Class Codes: H04L 45/02 Topology update or discovery
• CPC Class Codes: H04L 45/021 Ensuring consistency of routing table updates, e.g. by using epoch numbers
• CPC Class Codes: H04L 45/16 Multipoint routing
• CPC Class Codes: H04L 45/22 Alternate routing
• CPC Class Codes: H04L 45/24 Multipath
• CPC Class Codes: H04L 45/245 Link aggregation, e.g. trunking
• CPC Class Codes: H04L 45/28 using route fault recovery
• CPC Class Codes: H04L 45/48 Routing tree calculation
• CPC Class Codes: H04L 45/50 using label swapping, e.g. multi-protocol label switch [MPLS]
• CPC Class Codes: H04L 45/64 using an overlay routing layer
• CPC Class Codes: H04L 45/74 : Address processing for routing
• CPC Class Codes: H04L 45/745 : Address table lookup; Address filtering
• CPC Class Codes: H04L 45/7453 : using hashing
• CPC Class Codes: H04L 47/125 : by balancing the load, e.g. traffic engineering
• CPC Class Codes: H04L 49/70 : Virtual switches
• CPC Class Codes: H04L 51/214 : using selective forwarding
• CPC Class Codes: H04L 61/2503 : Translation of Internet protocol [IP] addresses
• CPC Class Codes: H04L 61/2592 : using tunnelling or encapsulation
• CPC Class Codes: H04L 67/10 : in which an application is distributed across nodes in the network software deployment G06F8/60; multiprogramming arrangements G06F9/46
• CPC Class Codes: H04L 69/22 : Parsing or analysis of headers

Abstract

The subject technology addresses the need in the art for directly measuring a maximum latency number with respect to a percentile of network traffic, which a network operator may utilize as an performance indication or metric. Given a traffic percentile, a tracking algorithm in accordance with embodiments described herein may be implemented in hardware and/or software to determine a maximum latency for this specific percentile of traffic.

Claims

1. A system, comprising:

at least one processor;

a network interface; and

memory including instructions that, when executed by the at least one processor, cause the system to perform operations comprising;

receiving a first set of packets at a network interface including a number of packets with a latency below a current threshold value;

updating the current threshold value, comprising;

increasing the current threshold value by LM*((L−

LF)/G), when LF is less than L;

decreasing the current threshold value by LM*((LF−

L)/G), when LF is greater than L;

wherein;

LF is a ratio of the number of packets with a latency below a current threshold value to a quantity of the first set of packets;

L is target ratio representing a latency percentage;

LM is a maximum latency value; and

G is a magnitude of adjustment.

2. The system of claim 1, wherein the first set of packets comprises an amount of packets received during a first period of time.

3. The system of claim 1, wherein the current threshold value comprises a predetermined value.

4. The system of claim 1, the operations further comprising:

determining whether a remaining period of time remains in a total amount of time for receiving packets.

5. The system of claim 1, the operations further comprising:

receiving a second set of packets at the network interface.

6. The system of claim 1, wherein the first set of packets are received at a respective port of the network interface, wherein the network interface includes a plurality of ports.

7. The system of claim 1, wherein the current threshold value comprises a predicted median percentile latency value according to an expected latency throughout a network.

8. A computer-implemented method, comprising:

receiving a first set of packets at a network interface including a number of packets with a latency below a current threshold value;

updating the current threshold value, comprising;

increasing the current threshold value by LM*((L−

LF)/G), when LF is less than L;

decreasing the current threshold value by LM*((LF−

L)/G), when LF is greater than L;

wherein;

LF is a ratio of the number of packets with a latency below a current threshold value to a quantity of the first set of packets;

L is target ratio representing a latency percentage;

LM is a maximum latency value; and

G is a magnitude of adjustment.

9. The computer-implemented method of claim 8, wherein the first set of packets comprises an amount of packets received during a first period of time.

10. The computer-implemented method of claim 8, wherein the current threshold value comprises a predetermined value.

11. The computer-implemented method of claim 8, further comprising:

determining whether a remaining period of time remains in a total amount of time for receiving packets.

12. The computer-implemented method of claim 8, further comprising:

receiving a second set of packets at the network interface.

13. The computer-implemented method of claim 8, wherein the first set of packets are received at a respective port of the network interface, wherein the network interface includes a plurality of ports.

14. The computer-implemented method of claim 8, wherein the current threshold value comprises a predicted median percentile latency value according to an expected latency throughout a network.

15. A non-transitory computer-readable medium including instructions stored therein that, when executed by at least one computing device, cause the at least one computing device to perform operations comprising:

receiving a first set of packets at a network interface including a number of packets with a latency below a current threshold value;

updating the current threshold value, comprising;

increasing the current threshold value by LM*((L−

LF)/G), when LF is less than L;

decreasing the current threshold value by LM*((LF−

L)/G), when LF is greater than L;

wherein;

LF is a ratio of the number of packets with a latency below a current threshold value to a quantity of the first set of packets;

L is target ratio representing a latency percentage;

LM is a maximum latency value; and

G is a magnitude of adjustment.

16. The non-transitory computer-readable medium of claim 15, wherein the first set of packets comprises an amount of packets received during a first period of time.

17. The non-transitory computer-readable medium of claim 15, wherein the current threshold value comprises a predetermined value.

18. The non-transitory computer-readable medium of claim 15, wherein the operations further comprise:

determining whether a remaining period of time remains in a total amount of time for receiving packets.

19. The non-transitory computer-readable medium of claim 15, wherein the operations further comprise:

receiving a second set of packets at the network interface.

20. The non-transitory computer-readable medium of claim 15, wherein the current threshold value comprises a predicted median percentile latency value according to an expected latency throughout a network.