Stateful LISP subscription for overlapping subnetworks

Patent metadata

Field	Value
Publication number	US-10999239-B2
Application number	US-201916715382-A
Country	US
Kind code	B2
Filing date	Dec 16, 2019
Priority date	May 26, 2017
Publication date	May 4, 2021
Grant date	May 4, 2021

Abstract

A Location/Identifier Separation Protocol (LISP) mapping server, including: a network interface for communicating with a LISP-enabled network; a mapping database; a subscription database; and an overlapping subscription publication engine (OSPE) to: receive a first mapping of a first subnetwork to a first routing locator (RLOC); add the first mapping to the mapping database; receive from a first ingress tunnel router (ITR) a subscription request for an endpoint identifier (EID) within the first subnetwork; add to a first subscription entry for the first subnetwork in the subscription database a subscription for the first ITR; receive a second mapping of a second subnetwork to a second RLOC, wherein the second subnetwork overlaps the first subnetwork; add the second mapping to the mapping database; and copy at least part of the first subscription entry to a second subscription entry for the second subnetwork.

First claim

What is claimed is:

1. A method comprising:
obtaining, by a mapping device, a second mapping of a second subnetwork to a second routing locator (RLOC), the second subnetwork partially overlapping with a first subnetwork mapped to a first RLOC in a first mapping stored in a mapping database;
adding, by the mapping device, the second mapping to the mapping database; and
subscribing, by the mapping device, an ingress tunnel router to the second subnetwork based on the ingress tunnel router being subscribed to the first subnetwork and by adding, in a subscription database, by the mapping device, a subscription entry in which the ingress tunnel router is subscribed to be notified of a routing change with respect to the second subnetwork.

2. The method of claim 1 , further comprising:
obtaining, by the mapping device, the first mapping of the first subnetwork to the first RLOC; and
adding, by the mapping device, the first mapping to the mapping database.

3. The method of claim 2 , further comprising:
obtaining, by the mapping device from the ingress tunnel router, a first subscription request for an endpoint identifier within the first subnetwork; and
adding, in the subscription database, by the mapping device, a first subscription entry in which the ingress tunnel router is subscribed to the first subnetwork.

4. The method of claim 3 , wherein subscribing the ingress tunnel router to the second subnetwork includes:
copying, by the mapping device, the first subscription entry to a second subscription entry in the subscription database for the second subnetwork.

5. The method of claim 4 , further comprising:
publishing, by the mapping device to the ingress tunnel router, a notification indicating that the ingress tunnel router is subscribed to the second subnetwork that overlaps with the first subnetwork.

6. The method of claim 1 , further comprising:
obtaining, from the subscription database, at least one subscription entry for another subnetwork that overlaps with the second subnetwork and has less specific prefixes than the second subnetwork; and
copying the at least one subscription entry to a second subscription entry for the second subnetwork.

7. The method of claim 1 , wherein subscribing to the second subnetwork includes searching, by the mapping device, through a radix tree and determining a longest matching prefix in the mapping database.

8. The method of claim 1 , wherein the first subnetwork has a first set of prefixes and the second subnetwork has a second set of prefixes that are more specific than the first set of prefixes.

9. An apparatus comprising:
a communication interface configured to enable network communications;
a memory configured to store executable instructions; and
a processor coupled to the communication interface and the memory and configured to perform operations including:
obtaining a second mapping of a second subnetwork to a second routing locator (RLOC), the second subnetwork partially overlapping with a first subnetwork mapped to a first RLOC in a first mapping stored in a mapping database;
adding the second mapping to the mapping database; and
subscribing an ingress tunnel router to the second subnetwork based on the ingress tunnel router being subscribed to the first subnetwork and by adding, in a subscription database, a subscription entry in which the ingress tunnel router is subscribed to be notified of a routing change with respect to the second subnetwork.

10. The apparatus of claim 9 , wherein the processor is further configured to perform the operations including:
obtaining the first mapping of the first subnetwork to the first RLOC; and
adding the first mapping to the mapping database.

11. The apparatus of claim 10 , wherein the processor is further configured to perform the operations including:
obtaining, from the ingress tunnel router, a first subscription request for an endpoint identifier within the first subnetwork; and
adding, in the subscription database, a first subscription entry in which the ingress tunnel router is subscribed to the first subnetwork.

12. The apparatus of claim 11 , wherein the processor performs subscribing the ingress tunnel router to the second subnetwork by:
copying the first subscription entry to a second subscription entry in the subscription database for the second subnetwork.

13. The apparatus of claim 12 , wherein the processor is further configured to perform the operations including:
publishing, to the ingress tunnel router, a notification indicating that the ingress tunnel router is subscribed to the second subnetwork that overlaps with the first subnetwork.

14. The apparatus of claim 9 , wherein the processor is further configured to perform the operations including:
obtaining, from the subscription database, at least one subscription entry for another subnetwork that overlaps with the second subnetwork and has less specific prefixes than the second subnetwork; and
copying the at least one subscription entry to a second subscription entry for the second subnetwork.

15. One or more non-transitory computer readable storage media encoded with software comprising computer executable instructions operable to perform operations comprising:
obtaining a second mapping of a second subnetwork to a second routing locator (RLOC), the second subnetwork partially overlapping with a first subnetwork mapped to a first RLOC in a first mapping stored in a mapping database;
adding the second mapping to the mapping database; and
subscribing an ingress tunnel router to the second subnetwork based on the ingress tunnel router being subscribed to the first subnetwork and by adding, in a subscription database, a subscription entry in which the ingress tunnel router is subscribed to be notified of a routing change with respect to the second subnetwork.

16. The one or more non-transitory computer readable storage media of claim 15 , wherein the operations further include:
obtaining the first mapping of the first subnetwork to the first RLOC; and
adding the first mapping to the mapping database.

17. The one or more non-transitory computer readable storage media of claim 16 , wherein the operations further include:
obtaining, from the ingress tunnel router, a first subscription request for an endpoint identifier within the first subnetwork; and
adding, in the subscription database, a first subscription entry in which the ingress tunnel router is subscribed to the first subnetwork.

18. The one or more non-transitory computer readable storage media of claim 17 , wherein subscribing the ingress tunnel router to the second subnetwork includes:
copying the first subscription entry to a second subscription entry in the subscription database for the second subnetwork.

19. The one or more non-transitory computer readable storage media of claim 18 , wherein the operations further include:
publishing, to the ingress tunnel router, a notification indicating that the ingress tunnel router is subscribed to the second subnetwork that overlaps with the first subnetwork.

20. The one or more non-transitory computer readable storage media of claim 15 , wherein the operations further include:
obtaining, from the subscription database, at least one subscription entry for another subnetwork that overlaps with the second subnetwork and has less specific prefixes than the second subnetwork; and
copying the at least one subscription entry to a second subscription entry for the second subnetwork.

Assignees

• Cisco Tech Inc

Inventors

• Arango Jesus
• Ermagan Vina
• Leong Johnson
• Hooda Sanjay Kumar

Classifications

• H04L43/08

  Monitoring or testing based on specific metrics, e.g. QoS, energy consumption or environmental parameters · CPC title

• H04L43/20

  the monitoring system or the monitored elements being virtualised, abstracted or software-defined entities, e.g. SDN or NFV · CPC title

• H04L61/5084

  Providing for device mobility (network addressing or numbering for mobility support in wireless networks H04W8/26; mobile IP H04W80/04) · CPC title

• H04L61/103 Primary

  across network layers, e.g. resolution of network layer into physical layer addresses or address resolution protocol [ARP] · CPC title

• H04L45/586

  of virtual routers · CPC title