Content delivery network routing using border gateway protocol

Patent metadata

Field	Value
Publication number	US-11178244-B2
Application number	US-201213569692-A
Country	US
Kind code	B2
Filing date	Aug 8, 2012
Priority date	Aug 9, 2011
Publication date	Nov 16, 2021
Grant date	Nov 16, 2021

Abstract

An announcement protocol may allow disparate, and previously incompatible, content delivery network caches to exchange information and cache content for one another. Announcement data may be stored by the respective caches, and used to determine whether a cache is able to service an incoming request. URL prefixes may be included in the announcements to identify the content, and longest-match lookups may be used to help determine a secondary option when a first cache determines that it lacks a requested content.

First claim

We claim:

1. A method comprising:
determining, by a computing device, a first value indicating a position, within a caching system, of the computing device relative to a server, wherein the caching system comprises a plurality of cache devices having respective values indicating respective positions relative to the server;
receiving, from a cache device of the plurality of cache devices, information indicating:
an identifier associated with a content item,
an address for the cache device, and
a second value indicating a position, within the caching system, of the cache device relative to the server;

determining, based on a comparison of the first value with the second value, that the cache device is closer, within the caching system, to the server than the computing device is to the server;
based on the determining that the cache device is closer to the server than the computing device is to the server, storing the received information;
receiving a request associated with the identifier; and
routing, based on the identifier and the stored information, the request to the cache device.

2. The method of claim 1 , wherein the identifier is a text or alphanumeric string that is not a fully qualified domain name.

3. The method of claim 1 , further comprising mapping the identifier with a corresponding routable address.

4. The method of claim 1 , wherein the receiving the information comprises receiving a border gateway protocol (BGP) announcement message that comprises the information, wherein the BGP announcement message further comprises a BGP announcement community tag, and
wherein the method further comprises segregating the plurality of cache devices into priority groups based on the BGP announcement community tag.

5. The method of claim 1 , further comprising sending, by the computing device, a first announcement message indicating a first domain, supported by the computing device, and a sub-domain of the first domain not supported by the computing device.

6. A method comprising:
determining, by a computing device, a first value indicating a position, within a caching system, of the computing device relative to a server, wherein the caching system comprises a plurality of cache devices having respective values indicating respective positions relative to the server;
receiving, from a cache device of the plurality of cache devices, information indicating:
an identifier,
an address for the cache device,
a community tag, and
a second value indicating a position, within the caching system, of the cache device relative to the server;

based on a comparison of the community tag to a priority setting of the computing device, storing the received information; and
causing, based on the community tag, segregating of the plurality of cache devices into a plurality of priority groups.

7. The method of claim 6 , further comprising:
determining, based on a comparison of the first value with the second value, that the cache device is closer, within the caching system, to the server than the computing device is to the server, wherein the storing the received information is further based on the determining that the cache device is closer to the server than the computing device is to the server;
receiving a request associated with the identifier; and
routing, based on the identifier and the stored information, the request to the cache device.

8. The method of claim 6 , further comprising rearranging, in the stored information, components of the identifier.

9. The method of claim 6 , wherein the identifier is a text or alphanumeric string that is not a fully qualified domain name.

10. A non-transitory computer-readable medium storing instructions that, when executed, cause:
determining, by a computing device, a first value indicating a position, within a caching system, of the computing device relative to a server, wherein the caching system comprises a plurality of cache devices having respective values indicating respective positions relative to the server;
receiving, from a cache device of the plurality of cache devices, information indicating:
an identifier associated with a content item,
an address for the cache device, and
a second value indicating a position, within the caching system, of the cache device relative to the server;

determining, based on a comparison of the first value with the second value, that the cache device is closer, within the caching system, to the server than the computing device is to the server;
based on the determining that the cache device is closer to the server than the computing device is to the server, storing the received information;
receiving a request associated with the identifier; and
routing, based on the identifier and the stored information, the request to the cache device.

11. The non-transitory computer-readable medium of claim 10 , wherein the instructions, when executed, further cause segregating the plurality of cache devices into priority groups based on community tags.

12. The non-transitory computer-readable medium of claim 10 , wherein the instructions, when executed, further cause rearranging, in the stored information, components of the identifier.

13. The method of claim 1 , wherein the received information further comprises a next-hop address.

14. The method of claim 1 , further comprising:
receiving, from a second cache device of the plurality of cache devices, second information indicating a third value indicating a position, within the caching system, of the second cache device relative to the server;
determining, based on a comparison of the third value with the first value, that the second cache device is farther away, within the caching system, from the server than the computing device is from the server; and
based on the determination that the second cache device is farther away from the server than the computing device is from the server, not storing the second information.

15. The method of claim 1 , further comprising:
forwarding the received information to a second cache device of the plurality of cache devices.

16. The method of claim 1 , further comprising:
determining, by the computing device, a sub-domain, of the content item, that the computing device does not handle; and
sending, to a second computing device, an indication of the sub-domain.

17. The non-transitory computer-readable medium of claim 10 , wherein the instructions, when executed, further cause:
receiving, from a second cache device of the plurality of cache devices, second information indicating a third value indicating a position, within the caching system, of the second cache device relative to the server;
determining, based on a comparison of the third value with the first value, that the second cache device is farther away, within the caching system, from the server than the computing device is from the server; and
based on the determination that the second cache device is farther away from the server than the computing device is from the server, not storing the second information.

18. The method of claim 1 , further comprising determining a third value indicating a position, within a second caching system different from the caching system, of the computing device relative to a second server, wherein the third value is different from the first value.

19. The non-transitory computer-readable medium of claim 10 , wherein the information is included in a border gateway protocol (BGP) announcement message.

20. The method of claim 1 , where

Assignees

• Field Brian
• Van Doorn Jan
• Hall Jim
• Comcast Cable Comm Llc

Inventors

• Field Brian
• Van Doorn Jan
• Hall Jim

Classifications

• H04L67/563 Primary

  Data redirection of data network streams · CPC title

• H04L67/63

  Routing a service request depending on the request content or context · CPC title

• H04L67/568

  Storing data temporarily at an intermediate stage, e.g. caching · CPC title

• H04L67/288 Primary

  Distributed intermediate devices, i.e. intermediate devices for interaction with other intermediate devices on the same level · CPC title

• H04L67/327

  Electricity · mapped topic