Content distribution network server management system architecture

• US 20030115281A1
• Filed: 08/06/2002
• Published: 06/19/2003
• Est. Priority Date: 12/13/2001
• Status: Abandoned Application

• Current Assignee: Fort Hill Systems
• Original Assignee: Fort Hill Systems
• Inventors: Koren, Dan, Veach, David L., Czarnik, Paul G., Schroeder, Carl J., Zink, David S., Caldecott, Neal, Trumbo-McHenry, Shari L., McHenry, Stephen T.
• Application Number:
  US10/213,653
• Publication Number:
  US 20030115281A1
• Time in Patent Office: Days
• US Class Current: 709/213
• CPC Class Codes: H04L 67/2895 Intermediate processing functionally located close to the data provider application, e.g. reverse proxies
• CPC Class Codes: H04L 67/565 Conversion or adaptation of application format or content adding application control or application functional data H04L67/561
• CPC Class Codes: H04L 67/5681 Pre-fetching or pre-delivering data based on network characteristics
• 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

Multi-proxy caches are located at the edge of a defined network domain to support multiple network clients. A portion of a multi-proxy cache is operated as a reverse proxy cache, providing access to predesignated content selectively distributed from one or more origin servers. Portions of the reverse proxy can be logically designated to cache pre-fetched content, while other portions can be designated to cache content retrieved on an as-requested basis. The reverse proxy caches can be limited to selectively caching content specified subject to a defined scope of content from one or more defined origin servers. Storage of content to the cache is subject to cache content replacement policies differentially specified for different classes of predesignated content. Remaining portions of the multi-proxy caches permit caching of forward proxy requested content.

Claims

1. A network cache control system providing for the managed storage of content, selectively drawn from an origin server, within a system of remotely distributed network edge caches, said network cache control system comprising:

a) a content discovery system coupleable to an origin server including a source content store, wherein said content discovery system includes a first rule base defining a source selection of content from said source content store; and

b) a content distribution control system coupled to said content discovery system and coupleable to a plurality of network edge cache systems having respective content caches, said content distribution control system including a second rule base defining the distribution of said source selection of content to said plurality of network edge cache systems, wherein said content distribution control system establishes respective subsets of said source selection of content for distribution to said plurality of network edge cache systems, and wherein first portions of said respective subsets are identified for prefetch and second portions are identified for fetch on request.

2. The network cache control system of claim 1 wherein said content distribution control system provides for the construction of said second rule base based on said first rule base.

3. The network cache control system of claim 2 wherein said content distribution control system is coupled to receive respective usage information from said plurality of network edge cache systems, and wherein said content distribution control system provides for the construction of said second rule base relative to said respective subsets based on said respective usage information.

4. The network cache control system of claim 1 wherein said content distribution control system distributes respective cache specifications of said respective subsets to said plurality of network edge cache systems and wherein instances of said source content identified in said respective cache specifications are associated with cache content eviction policies.

5. The network cache control system of claim 4 wherein said cache specifications provide for the application of said cache content eviction policies differentially with respect to said first and second portions of said respective subsets of said source selection of content.

6. The network cache control system of claim 5 further comprising an edge content storage control system, wherein instances of said edge content control system are respectively provided in said plurality of network edge cache systems, said edge content storage control system being coupleable to a plurality of network clients to receive content requests and including a third rule base providing for storage of a respective instance of said respective cache specifications, said edge content storage control system providing for implementation of said cache eviction policies defined by said respective instance.

7. The network cache control system of claim 6 wherein said edge content storage control system provides for prefetching said first portion defined by said respective instance and fetching on request said second portion defined by said respective instance for storage in a respective one of said content caches, subject to said cache eviction policies defined by said respective instance.

8. The network cache control system of claim 7 wherein said respective instance is periodically received by said edge content storage control system.

9. The network cache control system of claim 8 wherein said content distribution control system revises and redistributes said respective cache specifications.

10. A method of managing content stored by a distributed set of network edge caches for access by network clients, said method comprising the steps of:

a) creating a rule base associating cache persistence policies to preselected instances of content stored by an origin server, wherein said cache persistence policies include prefetch and fetch on-demand rules;

b) distributing said rule base to a network edge cache system;

c) managing the storage of first and second reverse proxy content in combination with third forward proxy content in a cache coupled to said network edge cache system, wherein said managing step includes processing said rule base to prefetch said first reverse proxy content and enable fetch on-demand of said second reverse proxy content and said third forward proxy content from said origin server to said cache, and wherein said managing step provides for the unified management of said cache storage space with respect to the storage of said first and second reverse proxy content and said third forward proxy content.

11. The method of claim 10 wherein said steps of creating and distributing are repeated to modify the identification of said preselected instances of content and the association of said cache persistence policies represented in said rule base and to reflect the modifications of said rule base in the storage of said first and second reverse proxy content and said third forward proxy content in said cache.

12. The method of claim 11 further comprising the step of maintaining meta-data descriptive of the content stored by said origin server, wherein said step of creating is responsive to said meta-data for repeating the creation of said rule base.

13. A network cache control system providing for the managed operation of network edge caches in support of the distribution of content within a bounded domain, said network cache control system comprising:

a) a network edge cache system including a content cache for storing forward proxy content and reverse proxy content within a unified cache storage space, said network edge cache system being responsive to client requests to provide content as available from said content cache and a predetermined content source; and

b) a content controller determining the reverse proxy content stored by said content cache, said content controller providing for the selection and grouping of first and second identifications of content accessible from said predetermined content source as reverse proxy content transferrable to said network edge cache system, wherein said first identifications determine reverse proxy content for prefetch by said network edge cache system to said content cache and said second identifications determine reverse proxy content for fetch on-demand by said network edge cache system to said content cache.

14. The network cache control system of claim 13 wherein said first and second identifications are recorded in a rules base distributed to said network edge cache system and wherein said network edge cache system executes an agent responsive to said rules base to provide for the prefetching of content corresponding to said first identifications and fetching content corresponding to said second identifications on-demand in response to client requests.

15. The network cache control system of claim 14 wherein said content controller provides for the repeated distribution of said rules base to said network edge cache system, wherein the content corresponding to said first and second identifications varies with the repeated distribution of said rules base.

16. The network cache control system of claim 15 wherein said content controller centrally provides for the generation of respective rule bases for a plurality of said network edge cache systems, said content controller providing for the separate distribution of said respective rule bases to said plurality of network edge cache systems.

17. A network cache control system providing for the controlled, remotely cached, distribution of content from one or more content origin servers to enable low latency access by network clients, said network cache control system comprising:

a) a plurality of network edge cache servers distributed remotely relative to a bounded content domain and respectively including content caches supporting storage of forward proxy content and reverse proxy content within unified cache storage spaces, said plurality of network edge cache servers operating said content caches responsive to the evaluation of respective rules bases; and

b) a central edge cache content controller, coupleable through a network to a content origin server, providing for the selective generation and distribution of said respective rules bases to said plurality of network edge cache servers, each said rules base including reverse proxy content specifications determined by said central edge cache content controller relative to meta-data descriptive of the content stored by said content origin server, first and second groups of said reverse proxy content specifications being identified in said rules bases to specify respectively prefetch of first reverse proxy content and on-demand fetch of second reverse proxy content.

18. The network cache control system of claim 17 wherein said bounded content domain includes a plurality of content origin servers and wherein said reverse proxy content specifications identify bounded sub-domains of content accessible from said plurality of content origin servers.

19. The network cache control system of claim 18 wherein said central edge cache content controller provides centralized administrative control over the selection of said reverse proxy content specifications for the respective said rules bases and of said first and second groups of said reverse proxy content specifications for the respective said rules bases.