Deadlock-Free Traffic Rerouting in Software-Defined Networking Networks

Patent metadata

Field	Value
Publication number	US-2019190819-A1
Application number	US-201715845280-A
Country	US
Kind code	A1
Filing date	Dec 18, 2017
Priority date	Dec 18, 2017
Publication date	Jun 20, 2019
Grant date	—

Abstract

Concepts and technologies disclosed herein are directed to deadlock-free traffic rerouting in software-defined networking (“SDN”) networks have been disclosed herein. According to one aspect of the concepts and technologies disclosed herein, a centralized SDN controller can determine that a packet flow along a path within at least a portion of a network is to be rerouted from the path to a new path. The centralized SDN controller can initiate a reroute of the packet flow to the new path. The centralized SDN controller can request a bandwidth for the new path. The bandwidth can be determined such that bandwidth oversubscription on the new path is avoided. In response to the packet flow settling on the new path, the centralized SDN controller can adjust a requested bandwidth of the packet flow to a desired value to complete the reroute of the packet flow from the path to the new path.

First claim

We claim:

1 . A centralized software-defined networking controller comprising:
a processor; memory having instructions stored thereon that, when executed by the processor, cause the processor to perform operations comprising
determining that a packet flow along a path within at least a portion of a network is to be rerouted from the path to a new path,
initiating a reroute of the packet flow to the new path,
requesting a bandwidth for the new path, wherein the bandwidth is determined such that bandwidth oversubscription on the new path is avoided, and
in response to the packet flow settling on the new path, adjusting a requested bandwidth of the packet flow to a desired value to complete the reroute of the packet flow from the path to the new path.

2 . The centralized software-defined networking controller of claim 1 , wherein:
the network comprises a multiprotocol label switching network; the path comprises a label switched path; and the new path comprises a new label switched path.

3 . The centralized software-defined networking controller of claim 1 , wherein the portion of the network comprises a network link between a first network node and a second network node.

4 . The centralized software-defined networking controller of claim 3 , wherein the first network node comprises a first router and the second network node comprises a second router.

5 . The centralized software-defined networking controller of claim 4 , wherein the first router and the second router are unable to perform rerouting to resolve congestion of the network link.

6 . The centralized software-defined networking controller of claim 5 , wherein the network link comprises a bandwidth capacity and the congestion results from a threshold percentage of the bandwidth capacity being reached or exceeded.

7 . A computer-readable storage medium comprising computer-executable instructions that, when executed by a processor of a centralized software-defined networking controller, causes the centralized software-defined networking controller to perform operations comprising:
determining that a packet flow along a path within at least a portion of a network is to be rerouted from the path to a new path; initiating a reroute of the packet flow to the new path; requesting a bandwidth for the new path, wherein the bandwidth is determined such that bandwidth oversubscription on the new path is avoided; and in response to the packet flow settling on the new path, adjusting a requested bandwidth of the packet flow to a desired value to complete the reroute of the packet flow from the path to the new path.

8 . The computer-readable storage medium of claim 7 , wherein:
the network comprises a multiprotocol label switching network; the path comprises a label switched path; and the new path comprises a new label switched path.

9 . The computer-readable storage medium of claim 7 , wherein the portion of the network comprises a network link between a first network node and a second network node.

10 . The computer-readable storage medium of claim 9 , wherein the first network node comprises a first router and the second network node comprises a second router.

11 . The computer-readable storage medium of claim 10 , wherein the first router and the second router are unable to perform rerouting to resolve congestion of the network link.

12 . The computer-readable storage medium of claim 11 , wherein the network link comprises a bandwidth capacity and the congestion results from a threshold percentage of the bandwidth capacity being reached or exceeded.

13 . A method comprising:
determining, by a centralized software-defined controller comprising a processor, that a packet flow along a path within at least a portion of a network is to be rerouted from the path to a new path; initiating, by the centralized software-defined controller, a reroute of the packet flow to the new path; requesting, by the centralized software-defined controller, a bandwidth for the new path, wherein the bandwidth is determined such that bandwidth oversubscription on the new path is avoided; and in response to the packet flow settling on the new path, adjusting, by the centralized software-defined controller, a requested bandwidth of the packet flow to a desired value to complete the reroute of the packet flow from the path to the new path.

14 . The method of claim 13 , wherein:
the network comprises a multiprotocol label switching network; the path comprises a label switched path; and the new path comprises a new label switched path.

15 . The method of claim 13 , wherein the portion of the network comprises a network link between a first network node and a second network node.

16 . The method of claim 15 , wherein the first network node comprises a first router and the second network node comprises a second router.

17 . The method of claim 16 , wherein the first router and the second router are unable to perform rerouting to resolve congestion of the network link.

18 . The method of claim 17 , wherein the network link comprises a bandwidth capacity and the congestion results from a threshold percentage of the bandwidth capacity being reached or exceeded.

19 . The method of claim 18 , further comprising:
determining, by the centralized software-defined controller, that a further packet flow along a further path within at least a further portion of the network is to be rerouted from the further path to a further new path; initiating, by the centralized software-defined controller, a further reroute of the further packet flow to the further new path; requesting, by the centralized software-defined controller, a further bandwidth for the further new path, wherein the further bandwidth is determined such that bandwidth oversubscription on the further new path is avoided; and in response to the further packet flow settling on the further new path, adjusting, by the centralized software-defined controller, a further requested bandwidth of the further packet flow to a further desired value to complete the further reroute of the further packet flow from the further path to the further new path.

20 . The method of claim 19 , wherein:
the further portion of the network comprises a further network link between a third network node and a fourth network node; the third network node comprises a third router and the fourth network node comprises a fourth router; the third router and the fourth router are unable to perform rerouting to resolve further congestion of the further network link; and the further network link comprises a further bandwidth capacity and the further congestion results from a further threshold percentage of the further bandwidth capacity being reached or exceeded.

Assignees

• At & T Ip I Lp

Inventors

• Choudhury Gagan
• Xi Kang
• Tse Simon
• Padi Narayan
• Goddard Alvin
• Raghuram Aswatnarayan

Classifications

• H04L41/0896

  Bandwidth or capacity management, i.e. automatically increasing or decreasing capacities (flow or congestion control using dynamic resource allocation, e.g. in-call renegotiation, H04L47/76) · CPC title

• H04L45/50

  using label swapping, e.g. multi-protocol label switch [MPLS] · CPC title

• H04L45/38 Primary

  Flow based routing · CPC title

• H04L47/2441

  relying on flow classification, e.g. using integrated services [IntServ] · CPC title

• H04L45/56

  Routing software · CPC title