Systems and methods for stateless symmetric forwarding

Patent metadata

Field	Value
Publication number	US-12592886-B2
Application number	US-202217813410-A
Country	US
Kind code	B2
Filing date	Jul 19, 2022
Priority date	Jul 19, 2022
Publication date	Mar 31, 2026
Grant date	Mar 31, 2026

Abstract

A system of one embodiment that provides stateless symmetric forwarding of packets in a computer network. The system includes a memory and a processor. The system is operable to determine a cluster state of a plurality of border routers in a cluster. The system is operable to communicate the cluster state to at least one branch node in the computer network. The system is operable to generate a network level consistent hash based on the cluster state. The system is operable to route a first packet through a first border router of the plurality of border routers in the cluster using the network level consistent hash. After the first packet is sent through a first border router, the system is further operable to route a second packet through the first border router of the plurality of border routers in the cluster using the network level consistent hash.

First claim

What is claimed is:

1 . A system, comprising:
one or more processors; and one or more computer-readable non-transitory storage media comprising instructions that, when executed by the one or more processors, cause one or more components of the system to perform operations comprising:
determining a first cluster state of a first plurality of border routers in a first cluster, wherein the first cluster is located between a core network and a first regional network;
determining a second cluster state of a second plurality of border routers in a second cluster, wherein the second cluster is located between the core network and a second regional network;
generating a network level consistent hash based on the first cluster state and the second cluster state;
receiving, by a first border router of the first plurality of border routers in the first cluster, a packet from a node in the first regional network;
selecting, from the first plurality of border routers and the second plurality of border routers, an owner border router using the network level consistent hash; and routing the packet to the owner border router.

2 . The system of claim 1 , wherein determining the first cluster state of the first plurality of border routers in the first cluster comprises implementing a bidirectional forwarding detection protocol.

3 . The system of claim 1 , wherein determining the second cluster state comprises receiving the second cluster state from a controller.

4 . The system of claim 1 , the operations further comprising:
diverting the packet received by the first border router by routing the packet from the owner border router in the first cluster using the network level consistent hash.

5 . The system of claim 1 , wherein generating the network level consistent hash based on the first cluster state and the second cluster state comprises generating a consistent hash table wherein a key to the consistent hash table comprises a five-tuple of the packet.

6 . The system of claim 1 , the operations further comprising:
updating the network level consistent hash based on a determination that the first cluster state of the first cluster has changed; and updating the network level consistent hash based on a determination that the second cluster state of the second cluster has changed.

7 . The system of claim 1 , wherein:
the first cluster state is communicated to nodes within the first regional network by a first controller but not to nodes exclusively within the second regional network; and the second cluster state is communicated to nodes within the second regional network by a second controller but not to nodes exclusively within the first regional network.

8 . A method, comprising:
determining a first cluster state of a first plurality of border routers in a first cluster, wherein the first cluster is located between a core network and a first regional network; determining a second cluster state of a second plurality of border routers in a second cluster, wherein the second cluster is located between the core network and a second regional network; generating a network level consistent hash based on the first cluster state and the second cluster state; receiving, by a first border router of the first plurality of border routers in the first cluster, a packet from a node in the first regional network; selecting, from the first plurality of border routers and the second plurality of border routers, an owner border router using the network level consistent hash; and routing the packet to the owner border router.

9 . The method of claim 8 , wherein determining the first cluster state of the first plurality of border routers in the first cluster comprises implementing a bidirectional forwarding detection protocol.

10 . The method of claim 8 , wherein determining the second cluster state comprises receiving the second cluster state from a controller.

11 . The method of claim 8 , further comprising:
diverting the packet received by the first border router by routing the packet from the owner border router in the first cluster using the network level consistent hash.

12 . The method of claim 8 , wherein generating the network level consistent hash based on the first cluster state and the second cluster state comprises generating a consistent hash table wherein a key to the consistent hash table comprises a five-tuple of the packet.

13 . The method of claim 8 , further comprising:
updating the network level consistent hash based on a determination that the first cluster state of the first cluster has changed; and updating the network level consistent hash based on a determination that the second cluster state of the second cluster has changed.

14 . The method of claim 8 , wherein:
the first cluster state is communicated to nodes within the first regional network by a first controller but not to nodes exclusively within the second regional network; and the second cluster state is communicated to nodes within the second regional network by a second controller but not to nodes exclusively within the first regional network.

15 . One or more computer-readable non-transitory storage media embodying instructions that, when executed by a processor, cause the processor to perform operations comprising:
determining a first cluster state of a first plurality of border routers in a first cluster, wherein the first cluster is located between a core network and a first regional network; determining a second cluster state of a second plurality of border routers in a second cluster, wherein the second cluster is located between the core network and a second regional network; generating a network level consistent hash based on the first cluster state and the second cluster state; receiving, by a first border router of the first plurality of border routers in the first cluster, a packet from a node in the first regional network; selecting, from the first plurality of border routers and the second plurality of border routers, an owner border router using the network level consistent hash; and routing the packet to the owner border router.

16 . The one or more computer-readable non-transitory storage media of claim 15 , wherein determining the first cluster state of the first plurality of border routers in the first cluster comprises implementing a bidirectional forwarding detection protocol.

17 . The one or more computer-readable non-transitory storage media of claim 15 , wherein determining the second cluster state comprises receiving the second cluster state from a controller.

18 . The one or more computer-readable non-transitory storage media of claim 15 , the operations further comprising:
diverting the packet received by the first border router by routing the packet from the owner border router in the first cluster using the network level consistent hash.

19 . The one or more computer-readable non-transitory storage media of claim 15 , the operations further comprising:
updating the network level consistent hash based on a determination that the first cluster state of the first cluster has changed; and updating the network level consistent hash based on a determination that the second cluster state of the second cluster has changed.

20 . The one or more computer-readable non-transitory storage media of claim 15 , wherein:
the first cluster state is communicated to nodes within the first regional network by a first controller but not to nodes exclusively within the second re

Assignees

• Cisco Tech Inc

Inventors

• Ponnuru Laxmikantha Reddy
• Thoria Samir
• Manickam Arul Murugan
• Singh Ram Dular

Classifications

• H04L45/04

  Interdomain routing, e.g. hierarchical routing · CPC title

• H04L45/64

  using an overlay routing layer · CPC title

• H04L45/02

  Topology update or discovery · CPC title

• H04L45/58

  Association of routers · CPC title

• H04L45/7453 Primary

  using hashing · CPC title