Event triggered traceroute for optimized routing in a computer network

• US 9,692,679 B2
• Filed: 10/15/2014
• Issued: 06/27/2017
• Est. Priority Date: 01/31/2008
• Status: Active Grant

• Current Assignee: Cisco Technology, Inc. (Cisco Systems, Inc.)
• Original Assignee: Cisco Technology, Inc. (Cisco Systems, Inc.)
• Inventors: Blair, Dana, Patel, Rahul G., Shah, Pritam
• Primary Examiner(s): SERRAO, RANODHI N
• Application Number:
  US14/515,452
• Publication Number:
  US 20150036478A1
• Time in Patent Office: 986 Days
• Field of Search: None
• CPC Class Codes: H04L 41/0668 by dynamic selection of recovery network elements, e.g. replacement by the most appropriate element after failure
• CPC Class Codes: H04L 41/0677 Localisation of faults
• CPC Class Codes: H04L 41/0686 Additional information in the notification, e.g. enhancement of specific meta-data
• CPC Class Codes: H04L 43/0858 One way delays
• CPC Class Codes: H04L 43/10 Active monitoring, e.g. heartbeat, ping or trace-route
• CPC Class Codes: H04L 47/125 by balancing the load, e.g. traffic engineering

Abstract

In one embodiment, a network device (e.g., a master controller) may detect an event on a current path in a computer network from a local network domain to a destination address prefix of a remote domain. In response, the device may dynamically (e.g., intelligently) determine a trace target destination address within the destination address prefix, and may perform (or request performance of) a Traceroute of the current path and a selection of alternate paths in the network from the local network domain to the trace target, where the Traceroute is adapted to obtain per-hop measurements along the respective traced path. The measurements may then be stored, for example, to be used for optimal path selection, fault identification reporting, etc.

Claims

1. A method comprising:

requesting, at a master controller in a local network domain, monitoring of an address prefix of a remote domain by an edge node in the local network domain;

detecting an out-of-policy event on a path from the local network domain to the address prefix of the remote domain;

determining a trace target destination address within the address prefix;

performing a route trace of the path;

based on the route trace, storing per-hop measurements along the path;

creating a fault identification report based on the per-hop measurements;

determining, based on the fault identification report, to redistribute traffic entering or leaving the local network domain, to yield a determination; and

based on the determination, redistributing traffic routed through the edge node, wherein redistributing the traffic further comprises performing one of;

associating new border gateway protocol (BGP) preference values with the traffic;

statically changing routing table contents of the edge node;

or

selecting an exit link to a plurality of destination prefixes.

2. The method of claim 1, further comprising:

receiving, from the edge node, network statistics associated with the address prefix; and

further performing the determination based on the network statistics.

3. The method of claim 1, wherein the out-of-policy event is one of a policy change, a timer-based trigger, a delay above a threshold, or an unreachable address prefix.

4. A system comprising:

a processor; and

a non-transitory computer-readable medium storing instructions which, when executed by the processor, cause the processor to perform operations comprising;

receiving, at an edge node in a local network domain from a master controller in the local network domain, a request to monitor an address prefix associated with a remote domain;

measuring network statistics regarding traffic associated with the address prefix by generating a probe packet to measure a parameter associated with reaching the address prefix from an originating node and transferring the probe packet to a target node associated with the address prefix, wherein the target node is a learned target that is learned (1) by monitoring the traffic and (2) by detecting a data connection between the edge node in the local network domain and the learned target in the remote domain; and

forwarding the network statistics to the master controller.

5. The system of claim 4, wherein measuring the network statistics comprises monitoring one of throughput, timing, latency, packet, loss, or reachability of the traffic.

6. The system of claim 4, wherein the parameter is one of jitter, delay, loss, or reachability.

7. The system of claim 4, wherein the probe packet is generated upon receiving a probe request from the master controller.

8. The system of claim 4, wherein the target node is a configured target that is manually configured by a user at the master controller.

9. The system of claim 4, wherein the learned target is a most frequently used node chosen from a plurality of learned targets in the remote domain.

10. The system of claim 4, wherein the learned target is a node with a highest traffic throughput among a plurality of learned targets in the remote domain.

11. The system of claim 4, wherein the non-transitory computer-readable storage medium stores additional instructions which, when executed by the processor, cause the processor to perform the operations further comprising:

transferring the probe packet to a plurality of target nodes associated with the address prefix.

12. The system of claim 4, wherein the master controller is configured to:

receive, from the edge node, the network statistics;

determine, based on the network statistics, to redistribute traffic entering or leaving the local network domain can be optimized, to yield a determination; and

based on the determination, redistributing traffic routed through the edge node, wherein redistributing the traffic further comprises performing one of;

associating new border gateway protocol (BGP) preference values with the traffic;

statically changing routing table contents of the edge node;

or

selecting an exit link to a plurality of destination prefixes.

13. A non-transitory computer-readable storage device storing instructions which, when executed by a processor, cause the processor to perform operations comprising:

detecting an out-of-policy event on a path from a local network domain to an address prefix of a remote domain;

identifying, within the remote domain, a trace target destination address having the address prefix;

performing a route trace by transferring probes to trace target destination address;

based on the route trace, storing per-hop measurements along the path; and

creating a fault identification report based on the per-hop measurements;

determining, based on the fault identification report, to redistribute traffic entering or leaving the local network domain can be optimized, to yield a determination; and

based on the determination, redistributing traffic routed through an edge node, wherein redistributing the traffic further comprises performing one of;

associating new border gateway protocol (BGP) preference values with the traffic;

statically changing routing table contents of the edge node;

or

selecting an exit link to a plurality of destination prefixes.

14. The non-transitory computer-readable storage device of claim 13, wherein the non-transitory computer-readable storage device stores additional instructions which, when executed by the processor, cause the processor to perform further operations comprising:

receiving, from the edge node, network statistics associated with the address prefix; and

further performing the determination based on the network statistics.