Filtering advertising of route advertisements based on virtual network identifiers

Patent metadata

Field	Value
Publication number	US-2021119829-A1
Application number	US-201916655158-A
Country	US
Kind code	A1
Filing date	Oct 16, 2019
Priority date	Oct 16, 2019
Publication date	Apr 22, 2021
Grant date	—

Abstract

Network identifiers are extracted from route advertisements. A table associates virtual network identifiers with provider edge devices. When a virtual network identifier extracted from a route advertisement matches a virtual network identifier in the table, the route advertisement is propagated to the provider edge devices associated with that virtual network identifier in the table. The route advertisement is not propagated to provider edge devices not associated with that virtual network identifier in the table.

First claim

What is claimed is:

1 . A method of providing route advertisements to provider edge devices on a virtual private network, the method comprising:
receiving, from a first provider edge device, a first route advertisement; extracting, from the first route advertisement, a virtual network identifier; determining whether a datastore associating provider edge devices with virtual network identifiers includes a record comprising the virtual network identifier; in response to determining that the datastore includes a record comprising the virtual network identifier:
identifying, based on the record, a second provider edge device associated with the virtual network identifier; and
transmitting, to the second provider edge device, the first route advertisement.

2 . The method of claim 1 , further comprising:
identifying a second route advertisement including the virtual network identifier; and transmitting, to the first provider edge device, the second route advertisement.

3 . The method of claim 1 , further comprising:
refraining from transmitting the first route advertisement to a third provider edge device that is not included in the record.

4 . The method of claim 1 , wherein the virtual network identifier comprises a virtual extensible local area network (VXLAN) network identifier.

5 . A method for building a route eligibility table, the method comprising:
receiving, from a provider edge device, a route advertisement; extracting, from the route advertisement, a virtual network identifier; determining whether a datastore associating provider edge devices with virtual network identifiers includes a record for the virtual network identifier; and in response to determining that the datastore does not include a record for the virtual network identifier, generating, for the datastore, a record comprising the virtual network identifier and an identifier of the provider edge device.

6 . The method of claim 5 , further comprising:
in response to determining that the datastore includes a record for the virtual network identifier, determining whether the record associates the provider edge device with the virtual network identifier; and in response to determining that the record does not associate the provider edge device with the virtual network identifier, adding an identifier of the provider edge device to the record to associate the provider edge device with the virtual network identifier.

7 . The method of claim 5 , wherein the virtual network identifier is a first virtual network identifier, the method further comprising:
determining whether the route advertisement includes a second virtual network identifier; in response to determining that the route advertisement includes a second virtual network identifier:
extracting the second virtual network identifier;
determining whether the datastore includes a record for the second virtual network identifier; and
in response to determining that the datastore does not include a record for the second virtual network identifier, generating, for the datastore, a record comprising the second virtual network identifier and the identifier of the provider edge device.

8 . The method of claim 7 , further comprising:
in response to determining that the datastore includes a record for the second virtual network identifier, determining whether the record includes the identifier of the provider edge device; and in response to determining that the record does not include the identifier of the provider edge device, adding the identifier of the provider edge device to the record.

9 . The method of claim 5 , wherein determining whether the record associates the provider edge device with the virtual network identifier comprises:
determining whether the virtual network identifier extracted from the route advertisement matches the virtual network identifier included in the record; in response to determining that the virtual network identifier extracted from the route advertisement matches the virtual network identifier included in the record, determining whether the record includes an identifier of the provider edge device; and in response to determining that the record includes an identifier of the provider edge device, determining that the record associates the provider edge device with the virtual network identifier extracted from the route advertisement.

10 . The method of claim 5 , wherein the provider edge device comprises a network device that connects to and advertises network reachability information for one or more virtual private networks.

11 . The method of claim 5 , further comprising:
receiving, from the provider edge device, a route withdrawal including the virtual network identifier; determining whether all routes that were advertised by the provider edge device and included the virtual network identifier have been withdrawn; and in response to determining that all routes that were advertised by the provider edge device and included the virtual network identifier have been withdrawn, removing the identifier of the provider edge device from the record for the virtual network identifier.

12 . The method of claim 11 , further comprising:
determining whether the record includes an identifier of another provider edge device; in response to determining that the record includes an identifier of another provider edge device, transmitting the route withdrawal to the other provider edge device; and in response to determining that the record does not include an identifier of another provider edge device, deleting the record.

13 . The method of claim 11 , further comprising:
identifying a route that was previously advertised to the provider edge device, the route including the virtual network identifier; and transmitting, to the provider edge device, a route withdrawal for the identified route.

14 . The method of claim 5 , wherein the route advertisement includes an ethernet virtual private network (EVPN) type 3 route.

15 . A system of providing route advertisements to provider edge devices on a virtual private network, the system comprising:
a network interface configured to receive, from a first provider edge device, a first route advertisement; and control circuitry configured to:
extract, from the first route advertisement, a virtual network identifier;
determine whether a datastore associating provider edge devices with virtual network identifiers includes a record comprising the virtual network identifier;
in response to determining that the datastore includes a record comprising the virtual network identifier:
identify, based on the record, a second provider edge device associated with the virtual network identifier; and
transmit, via the network interface to the second provider edge device, the first route advertisement.

16 . The system of claim 15 , wherein the control circuitry is further configured to:
identify a second route advertisement including the virtual network identifier; and transmit, via the network interface to the first provider edge device, the second route advertisement.

17 . The system of claim 15 , wherein the control circuitry is further configured to refrain from transmitting the first route advertisement to a third provider edge device that is not included in the record.

18 . The system of claim 15 , wherein the virtual network identifier comprises a virtual extensible local area network (VXLAN) network identifier.

19 . A system for building a route eligibility table, the system com

Assignees

• Arista Networks Inc

Inventors

• Ranpise Amit Dattatray
• Lo Alton
• Singh Nitin

Classifications

• H04L45/02

  Topology update or discovery · CPC title

• H04L45/033

  by updating distance vector protocols · CPC title

• H04L12/4675 Primary

  Dynamic sharing of VLAN information amongst network nodes (configuration of the network or of network elements H04L41/08) · CPC title

• H04L45/025 Primary

  Updating only a limited number of routers, e.g. fish-eye update · CPC title

• H04L2101/618

  Details of network addresses · CPC title