US-12627476-B2 - End-to-end encryption with per-hop path-selection based on unique edge identities for SD-WAN and multi-hop networks

Abstract

A system and associated methods provide solutions for end-to-end privacy and per-hop routing and policy decision in multi-hop and Software-Defined Wide Area Networks (SD-WANs) by leveraging unique SDWAN edge identities of edge devices. The system enables end-to-end encryption between traffic source and destination sites using IPsec ESP tunnel mode, with System IPs as the outer IP addresses. The system further enables per-hop integrity protection using IPsec AH transport mode, with WAN IPs as the outer IP addresses. By having some information encrypted between a source device and a destination device and other information encapsulated between hops (e.g., between source device and an intermediate device), the system enables route and policy lookup based on destination site System-IP, along with integrity protection based on SLA-class in packet metadata for independent path selection at intermediate hops.

Inventors

• Amjad Inamdar
• Laxmikantha Reddy Ponnuru
• Syed Arslan Ahmed
• Anoop V A
• Jai Prakash Agrawal

Assignees

• CISCO TECHNOLOGY, INC.

Dates

Publication Date

20260512

Application Date

20231205

Claims (20)

1. 1 . A method, comprising: encrypting, at a source device of a network and using a destination encryption key, a payload of a packet destined for transmission to a destination device of the network, the destination device being uniquely associated with the destination encryption key and a destination device identifier; encapsulating, at the source device and using an intermediate authentication header key uniquely associated with an intermediate device of the network, the payload, the destination device identifier and metadata within an intermediate authentication header of the packet, the metadata indicating a class of traffic associated with the packet; and transmitting, by a network interface of the source device and over the network, the packet having the intermediate authentication header to the intermediate device.
2. 2 . The method of claim 1 , further comprising: accessing, at the source device, destination information received from a controller of the network, the destination information including the destination device identifier and the destination encryption key of the destination device.
3. 3 . The method of claim 1 , further comprising: accessing, at the source device, intermediate authentication header information received from a controller of the network, the intermediate authentication header information including an intermediate network address and the intermediate authentication header key uniquely associated with the intermediate device; and adding, at the source device, routing information to the packet external to the intermediate authentication header, the routing information indicating the intermediate network address of the intermediate device.
4. 4 . The method of claim 1 , the intermediate device of the network being operable for: decapsulating, at the intermediate device and using the intermediate authentication header key, the intermediate authentication header of the packet; accessing, at the intermediate device, destination authentication header information received from a controller of the network that includes a destination network address and a destination authentication header key uniquely associated with the destination device; encapsulating, at the intermediate device and using the destination authentication header key, the payload, the destination device identifier, and the metadata within a destination authentication header; and transmitting, by a network interface of the intermediate device and over the network, the packet with the destination authentication header to the destination device based on the destination network address of the destination device.
5. 5 . The method of claim 4 , the intermediate device of the network being operable for: accessing, at the intermediate device, policy information associated with the packet based on the metadata for transmission of the packet to the destination device in accordance with the policy information.
6. 6 . The method of claim 4 , the destination device of the network being operable for: decrypting, at the destination device, the packet using the destination encryption key.
7. 7 . The method of claim 6 , the destination device identifier and the metadata being encapsulated within the destination authentication header and the destination device of the network being operable for: decapsulating, at the destination device and using a destination authentication header key uniquely associated with the destination device, the destination authentication header of the packet.
8. 8 . The method of claim 1 , the source device being operable for encrypting the payload using an Internet Protocol Security (IPsec) Encapsulating Security Payload (ESP) protocol.
9. 9 . The method of claim 1 , the source device being operable for encapsulating the intermediate authentication header using an Internet Protocol Security (Ipsec) Authentication Header (AH) protocol.
10. 10 . The method of claim 1 , the destination device identifier being a hash.
11. 11 . A method, comprising: decapsulating, at an intermediate device of a network and using an intermediate authentication header key uniquely associated with the intermediate device, an intermediate authentication header of a packet received from a source device of the network for transmission to a destination device of the network; identifying, at the intermediate device, the destination device of the network; encapsulating, at the intermediate device and using a destination authentication header key uniquely associated with the destination device, a payload of the packet within a destination authentication header; and transmitting, by a network interface of the intermediate device and over the network, the packet with the destination authentication header to the destination device based on a destination network address of the destination device.
12. 12 . The method of claim 11 , further comprising: accessing, at the intermediate device and following decapsulation of the intermediate authentication header, a destination device identifier that is uniquely associated with the destination device; and accessing, at the intermediate device, information received from a controller of the network that includes the destination network address and the destination authentication header key uniquely associated with the destination device.
13. 13 . The method of claim 11 , further comprising: accessing, at the intermediate device, metadata of the packet indicating a class of traffic associated with the packet; and accessing, at the intermediate device, policy information associated with the packet based on the metadata for transmission of the packet to the destination device in accordance with the policy information.
14. 14 . The method of claim 11 , the destination authentication header encapsulating the payload of the packet, a destination device identifier, and metadata of the packet; the payload being encrypted by a source device in communication with the intermediate device using a destination encryption key uniquely associated with the destination device; the metadata indicating a class of traffic associated with the packet; and the destination device identifier being uniquely associated with the destination device.
15. 15 . The method of claim 11 , further comprising: adding, at the intermediate device, routing information to the packet following encapsulation of the packet within the destination authentication header, the routing information indicating the destination network address of the destination device.
16. 16 . The method of claim 11 , the destination device of the network being operable for: decrypting, at the destination device, the packet using a destination encryption key uniquely associated with the destination device.
17. 17 . The method of claim 16 , the destination device of the network being operable for: decapsulating, at the destination device and prior to decryption of the packet, the destination authentication header of the packet using a destination authentication header key uniquely associated with the destination device.
18. 18 . The method of claim 16 , the destination device being operable for decrypting the payload using an Internet Protocol Security (IPsec) Encapsulating Security Payload (ESP) protocol.
19. 19 . The method of claim 11 , the intermediate device being operable for encapsulating the destination authentication header using an Internet Protocol Security (IPsec) Authentication Header (AH) protocol.
20. 20 . A system, comprising: a processor in communication with a memory and a network interface, the memory including instructions executable by the processor to: encrypt, using a destination encryption key, a payload of a packet destined for transmission to a destination device of a network, the destination device being uniquely associated with the destination encryption key and a destination device identifier; encapsulate, using an intermediate authentication header key uniquely associated with an intermediate device of the network, the payload, the destination device identifier and metadata within an intermediate authentication header of the packet, the metadata indicating a class of traffic associated with the packet; and transmit, by the network interface and over the network, the packet having the intermediate authentication header to the intermediate device.

Description

BACKGROUND SD-WAN (Software-Defined Wide Area Network) services are commonly deployed across a plurality of different “branches” of an SD-WAN, where each “branch” can represent a site (e.g., an office) of an interconnected network. Most of the SD-WAN solutions in the market today from different vendors use hub-spoke topologies, that allow for better scalability of the number of sites as well as hierarchical design for global multi-region deployments. However, hub-spoke topology involves per-hop encryption, which incurs overhead and latency with increasing complexity of the SD-WAN and also involves security risks, as customer traffic is exposed at each intermediate hop. BRIEF DESCRIPTION OF THE SEVERAL VIEWS OF THE DRAWINGS Details of one or more aspects of the subject matter described in this disclosure are set forth in the accompanying drawings and the description below. However, the accompanying drawings illustrate only some typical aspects of this disclosure and are therefore not to be considered limiting of its scope. Other features, aspects, and advantages will become apparent from the description, the drawings and the claims. FIG. 1 illustrates an example of a high-level network architecture in accordance with some aspects of the present technology; FIG. 2 illustrates an example of a network topology in accordance with some aspects of the present technology; FIG. 3 illustrates an example of a diagram showing the operation of a protocol for managing an overlay network in accordance with some aspects of the present technology; FIG. 4A illustrates per-hop encryption; FIG. 4B illustrates end-to-end encryption; FIG. 4C illustrates a system for end-to-end encryption with per-hop integrity protection and decision making in accordance with some aspects of the present technology; FIG. 5A illustrates a sequence diagram showing processing of a packet at a source device in accordance with some aspects of the present technology; FIG. 5B illustrates a sequence diagram showing processing of the packet of FIG. 5A at an intermediate device in accordance with some aspects of the present technology; FIG. 5C illustrates a sequence diagram showing processing of the packet of FIG. 5A at a destination device in accordance with some aspects of the present technology; FIGS. 6A and 6B collectively illustrate a method for managing end-to-end encryption with per-hop integrity protection in accordance with some aspects of the present technology; and FIG. 7 illustrates an example of a network device according to some aspects of the present disclosure. DESCRIPTION OF EXAMPLE EMBODIMENTS The detailed description set forth below is intended as a description of various configurations of embodiments and is not intended to represent the only configurations in which the subject matter of this disclosure can be practiced. The appended drawings are incorporated herein and constitute a part of the detailed description. The detailed description includes specific details for the purpose of providing a more thorough understanding of the subject matter of this disclosure. However, it will be clear and apparent that the subject matter of this disclosure is not limited to the specific details set forth herein and may be practiced without these details. In some instances, structures and components are shown in block diagram form in order to avoid obscuring the concepts of the subject matter of this disclosure. Overview Techniques described herein provide procedures for providing end-to-end encryption and per-hop integrity protection in SD-WAN and multi-hop networks, while allowing intermediate devices with pertinent information to make informed routing and policy decisions without sacrificing privacy. In one aspect, a method for providing end-to-end encryption and per-hop integrity protection in SD-WAN and multi-hop networks includes: encrypting, at a source device of a network and using a destination encryption key, a payload of a packet destined for transmission to a destination device of the network, the destination device being uniquely associated with the destination encryption key and a destination device identifier; encapsulating, at the source device and using an intermediate authentication header key uniquely associated with an intermediate device of the network, the payload, the destination device identifier and metadata within an intermediate authentication header of the packet, the metadata indicating a class of traffic associated with the packet; and transmitting, by a network interface of the source device and over the network, the packet having the intermediate authentication header to the intermediate device. The method can further include: accessing, at the source device, destination information received from a controller of the network, the destination information including the destination device identifier and the destination encryption key of the destination device. The method can further include: accessing, at the source devic