SDWAN overlay routing service

1. A method, comprising:

receiving identification information regarding a software-defined wide area network (SDWAN) device;

authenticating the SDWAN device;

synchronizing a SDWAN routing service with the SDWAN device based on latest state and local route prefixes associated with the SDWAN device; and

publishing new states to the SDWAN device commensurate with routes created by the SDWAN routing service based on the latest state and local route prefixes.

2. The method of claim 1 , wherein the SDWAN routing service comprises a cloud branch gateway protocol (BGP) microservice implemented across a cluster of cloud BGP servers and a cluster of path computation modules (PCMs).

3. The method of claim 2 , wherein a first cloud BGP server of the cluster of cloud BGP servers publishes the latest state and local route prefixes from an overlay agent of the SDWAN device to a first PCM of the cluster of PCMs.

4. The method of claim 3 , wherein the overlay agent and the first cloud BGP server communicate across an overlay agent channel, the overlay agent channel being assigned in accordance with a load-balancing mechanism binding a tenant operating the SDWAN device and the cluster of BGP servers.

5. The method of claim 4 , wherein the load-balancing mechanism is based on one of a hypertext transfer protocol (HTTP) header or uniform resource locator (URL) associated with the tenant.

6. The method of claim 5 , further comprising inserting a custom header onto packets transmitted on the overlay agent channel based on the one of the HTTP header or URL associated with the tenant.

7. The method of claim 4 , wherein the first cloud BGP server performs the publishing of the new states to the overlay agent of the SDWAN device, upon publishing of the new states by the first PCM to the first cloud BGP server.

8. The method of claim 4 , further comprising establishing the overlay agent channel based on a specific virtual Internet Protocol (VIP) address associated with the SDWAN routing service such that control plane traffic of the SDWAN routing service is isolated from management plane traffic of the SDWAN routing service.

9. The method of claim 4 , wherein an elastic load-balancing component of the SDWAN routing service terminates the overlay agent channel as a secure channel and establishes the overlay agent channel as a plain-text channel to the first cloud BGP server.

10. The method of claim 4 , further comprising managing the load-balancing mechanism by a PCM scheduler component based on a number of active PCMs, a number of SDWAN devices associated with a tenant, a number of tunnels for the tenant, and a latest state update associated with the tenant.

11. The method of claim 10 , further comprising storing a tenant-to-PCM mapping and tenant-relevant information reflected by the load-balancing mechanism in a distributed key-value store of the SDWAN routing service.

12. The method of claim 11 , further comprising discovering each PCM of the cluster of PCMs via the tenant-to-PCM mapping and tenant-relevant information reflected in the distributed key-value store, each of the PCMs registering with the distributed key-value store upon operation initialization.

13. The method of claim 12 , further comprising initiating, by the PCM scheduler, keep-alive and periodic health check operations directed to each PCM of the cluster of PCMs using remote procedure calls.

14. The method of claim 3 , wherein the overlay agent operatively connects to an underlay routing daemon to obtain the local route prefixes.

15. A system providing a software-defined wide area network (SDWAN) overlay routing service, comprising:

a plurality of cloud branch gateway protocol (BGP) servers that together, comprise a cloud BGP microservice to:

receive information identifying a SDWAN device and authenticate the SDWAN device; and

a cluster of path computation modules (PCMs) that together, comprise a PCM microservice to:

synchronize routes associated with the SDWAN device based on latest state and local route prefixes associated with the SDWAN device; and

publish new states to the SDWAN device commensurate with routes created by the SDWAN routing service based on the latest state and local route prefixes.

16. The system of claim 15 , wherein the cloud BFP microservice receives the information identifying the SDWAN device from an overlay agent implemented at the SDWAN device, the overlay agent connecting to an underlay routing daemon to obtain the local route prefixes and transmitting the information via an overlay agent channel.

17. The system of claim 16 , wherein the overlay agent establishes the overlay agent channel based on a specific virtual Internet Protocol (VIP) address associated with system such that control plane traffic of the SDWAN overlay routing service is isolated from management plane traffic of the SDWAN overlay routing service.

18. The system of claim 16 , wherein the cloud BGP microservice publishes the latest state and local route prefixes from the overlay agent of the SDWAN device to the PCM microservice.

19. The system of claim 16 , wherein the overlay agent channel is assigned in accordance with a load-balancing mechanism binding a tenant operating the SDWAN device and the plurality of cloud BGP servers.

20. The system of claim 19 , further comprising a PCM scheduler component to manage the load-balancing mechanism based on a number of active PCMs, a number of SDWAN devices associated with the tenant, a number of tunnels for the tenant, and a latest state update associated with the tenant.