Method and apparatus for internet cache content delivery via a data distribution system

• US 6,427,172 B1
• Filed: 07/20/1999
• Issued: 07/30/2002
• Est. Priority Date: 07/20/1999
• Status: Expired due to Term

• Current Assignee: Telesat Network Services, Inc. (MHR Holdings LLC (New York))
• Original Assignee: CyberStar LP
• Inventors: Wright, Michael, Thacker, John C.
• Primary Examiner(s): Najjar, Saleh
• Application Number:
  US09/356,997
• Time in Patent Office: 1,106 Days
• Field of Search: 709/200, 709/203, 709/217, 709/219, 709/225, 709/226, 709/229, 709/235
• US Class Current: 709/235
• CPC Class Codes: G06F 16/9574 of access to content, e.g. by caching
• CPC Class Codes: H04B 7/18523 Satellite systems for providing broadcast service to terrestrial stations, i.e. broadcast satellite service arrangements specially adapted for satellite broadcast receiving H04H40/90; picture transmission via satellite H04N1/00103; television transmission via satellite H04N7/20
• CPC Class Codes: H04L 67/2885 Hierarchically arranged intermediate devices, e.g. for hierarchical caching
• CPC Class Codes: H04L 67/5682 Policies or rules for updating, deleting or replacing the stored data
• CPC Class Codes: H04L 69/329 in the application layer [OSI layer 7]
• CPC Class Codes: H04L 9/40 Network security protocols

Abstract

A cache system and caching methods that are used to improve data delivery service provided by a data distribution system. The present invention uses a master cache in which predictive harvesting of content is performed based upon probability distributions of individual caches satisfying requests from users. Content in the master cache is distributed to user sites by way of the data distribution system, and local caches at user sites are automatically loaded with incoming content.

Claims

1. A caching system for use with a data distribution system, comprising:

a master cache for receiving content for distribution by the data distribution system to one or more users;

a gateway for receiving content that is distributed by the data distribution system from the master cache;

one or more local caches for storing the content received by the gateway destined for the one or more users; and

harvesting software coupled to the master cache and the gateway for processing information corresponding to probability distributions that the local caches satisfy requests from their respective users to predictively distribute the desired content to the respective users.

2. The system recited in claim 1 wherein the harvesting software processes information contained in transmit hit/miss data and probability tables generated at the gateway.

3. The system recited in claim 1 wherein the content comprises http objects.

4. The system recited in claim 1 wherein the content comprises nttp objects.

5. The system recited in claim 1 wherein the gateway comprises:

at pseudo client for receiving an entitlement message indicating that that content has arrived at the gateway, for enabling the gateway as a sibling cache for the local cache for requesting content to be transferred from the sibling cache to the local cache, for verifying that content has been transferred to the local cache during the transfer process, for disabling the gateway as a sibling cache of the local cache at the completion of the process;

and wherein the local cache retrieves the content from the sibling cache until all content has been transferred.

6. The system recited in claim 5 wherein the Internet Protocol is used to communicate between the local cache and the sibling cache.

7. The system recited in claim 5 wherein the Internet Cache Protocol is used to communicate between the local cache and the sibling cache.

8. The system recited in claim 1 wherein the harvesting software:

processes statistics derived from the master cache and the local caches to produces a list of content to add to the master cache and a list of content to delete from the master cache;

forms a pseudo client to retrieve and verify the content to be added to the master cache; and

transmits the verified content from the master cache to the local caches.

9. The system recited in claim 1 wherein the harvesting software:

processes statistics derived from the master cache and the local caches to produces a list of content to add to the master cache and a list of content to delete from the master cache;

forms a pseudo client to retrieve and verify the content to be added to the master cache; and

transmits the verified content from the master cache to the local caches.

10. The system recited in claim 1 wherein the data distribution system, comprises a satellite-based data distribution system.

11. A method for transferring content distributed by a data distribution system to a gateway into a local cache, comprising the steps of:

creating a pseudo client on the gateway;

receiving an interrupt at the pseudo client indicating that that content has arrived at the gateway;

enabling the gateway as a sibling cache for the local cache;

requesting content to be transferred from the sibling cache to the local cache;

verifying that content has been transferred to the local cache during the transfer process;

disabling the gateway as a sibling cache of the local cache at the completion of the process; and

causing the local cache to retrieve the content from the sibling cache until all content has been transferred.

12. The method recited in claim 11 wherein the data distribution system, comprises ma satellite-based data distribution system.

13. A method for building a master cache used to transfer content by way of a data distribution system to a local cache, comprising the steps of:

processing statistics derived from the master cache and the local cache to produces a list of content to add to the master cache and a list of content to delete from the master cache;

forming a pseudo client to retrieve and verify the content to be added to the master cache; and

transmitting the verified content from the master cache to the local cache.

14. The method recited in claim 13 wherein the step of processing statistics comprises the step of processing information corresponding to probability distributions that the local caches satisfy requests from their respective users to predictively distribute the desired content to the respective users.

15. The method recited in claim 13 wherein the step of processing statistics comprises the step of processing information contained in transmit hit/miss data and probability tables.

16. A caching system for use with a data distribution system, comprising:

a master cache for receiving content for distribution by the data distribution system to one or more user computers,

a gateway that is distinct from the one or more user computers for receiving content that is distributed by the data distribution system from the master cache;

one or more local caches for storing the content received by the gateway destined for the one or more user computers; and

harvesting software coupled to the master cache and the gateway for processing information corresponding to probability distributions that the local caches satisfy requests from their respective users to predictively distribute the desired content to the respective user computers.

17. The system recited in claim 16 wherein the harvesting software processes information contained in transmit hit/miss data and probability tables generated at the gateway.

18. The system recited in claim 16 wherein the gateway comprises:

a pseudo client for receiving an entitlement message indicating that that content has arrived at the gateway, for enabling the gateway as a sibling cache for the local cache, for requesting content to be transferred from the sibling cache to the local cache, for verifying that content has been transferred to the local cache during the transfer process, for disabling the gateway as a sibling cache of the local cache at the completion of the process;

and wherein the local cache retrieves the content from the sibling cache until all content has been transferred.

19. The system recited in claim 16 wherein the data distribution system, comprises a satellite-based data distribution system.