Accessing data in a data processing system

• US 20070185848A1
• Filed: 03/15/2007
• Published: 08/09/2007
• Est. Priority Date: 04/11/1995
• Status: Active Grant

• Current Assignee: PersonalWeb Technologies, L.L.C.
• Original Assignee: Kinetech, Inc. (Brilliant Digital Entertainment Incorporated), Level 3 Communications LLC (Lumen Technologies, Inc.)
• Inventors: Farber, David, Lachman, Ronald
• Granted Patent: US 8,082,262 B2
• Time in Patent Office: Days
• US Class Current: 1/1
• CPC Class Codes: G06F 16/13 File access structures, e.g. distributed indices arrangements of input from, or output to, record carriers G06F3/06
• CPC Class Codes: G06F 16/164 File meta data generation
• CPC Class Codes: G06F 16/174 Redundancy elimination performed by the file system management of the data involved in backup or backup restore using de-duplication of the data G06F11/14
• CPC Class Codes: Y10S 707/914 Video
• CPC Class Codes: Y10S 707/915 Image
• CPC Class Codes: Y10S 707/916 Audio
• CPC Class Codes: Y10S 707/922 Communications
• CPC Class Codes: Y10S 707/959 Network
• CPC Class Codes: Y10S 707/961 Associative
• CPC Class Codes: Y10S 707/966 Distributed
• CPC Class Codes: Y10S 707/99931 Database or file accessing
• CPC Class Codes: Y10S 707/99932 Access augmentation or optimizing
• CPC Class Codes: Y10S 707/99933 Query processing, i.e. searching
• CPC Class Codes: Y10S 707/99942 Manipulating data structure, e.g. compression, compaction, compilation

Abstract

A plurality of data items are distributed across a plurality of computers, some of which may form a peer-to-peer network. A first computer receives a request for a data item from a requesting computer. The request includes a True Name of the data item. The first computer causes the requesting computer to obtain the data item from a second computer, distinct from the first computer. The first computer may not have a copy of the requested data item. The first computer may know the location of the data item. The first computer may forward the request for the data item to at least one other computer.

Claims

1. In a system in which a plurality of data items are distributed across a plurality of computers, a method comprising:

at a first computer,

(a) receiving from a requesting computer, a request for a data item, the request including a True Name of the data item; and

(b) causing said requesting computer to obtain said data item from a second computer, distinct from said first computer.

2. A method as in claim 1 wherein the first computer does not have a copy of the requested data item.

3. A method as in claim 1 wherein the first computer knows the location of the data item.

4. A method as in claim 1 wherein the first computer forwards the request for the data item to at least one other computer.

5. A method as in claim 4 wherein the at least one other computer includes the second computer.

7. A method as in claim 1 or claim 6 wherein the data item may comprise a file, a portion of a file, a page in memory, a digital message, a digital image, a video signal or an audio signal.

8. A method as in claim 1 or claim 6 wherein at least some of said computers communicate with each other using a TCP/IP communication protocol.

9. A method as in claim 1 or claim 6 wherein the True Name is computed using a message digest function or a hash function.

10. A method as in claim 1 or claim 6 wherein the True Name is computed using a function selected from:

MD4, MD5, and SHA.

11. A method as in claim 1 or claim 6 wherein the True Name is computed using a function that randomly distributes its outputs.

12. A method as in claim 1 or claim 6 wherein the True Name is computed using a function that produces a substantially unique value based on the data comprising the data item.

13. A method as in claim 1 or claim 6 wherein a data item may comprise a file, a portion of a file, a page in memory, a digital message, a digital image, a video signal or an audio signal.

14. A method as in claim 1 or claim 6 wherein said True Name for said data file will change when the data file is modified.

15. A method as in claim 1 or claim 6 wherein at least some of the plurality of computers make up part of a peer-to-peer network of computers.

16. A method as in claim 1 wherein said data item is a portion of a file, and wherein said first computer causes said requesting computer to obtain the data item from a location having a copy of the file.

6. In a system in which a plurality of data items are distributed across a plurality of computers, a method comprising:

at a first computer,

(a) receiving from a requesting computer, a request for a data item, the request including a True Name of the data item;

(b) identifying a second computer, distinct from the first computer, that should have a copy of the requested data item; and

(c) forwarding the request to the second computer.

17. A method as in claim 6 wherein said data item is a portion of a file, and wherein said first computer forwards said requesting computer to a location having a copy of the file.

18. In a system in which a plurality of data items are distributed across a plurality of computers, at least some of the plurality of computers forming part of a peer-to-peer (P2P) network of computers, a method comprising:

at a first computer,

(a) receiving from a requesting computer in said peer-to-peer network, a request for a data item, the request including a True Name of the data item;

(b) identifying a second computer in said P2P network that should have a copy of the requested data item, said second computer being distinct from the first computer; and

(c) forwarding the request to the second computer,

wherein the data item may comprise a file, a portion of a file, a page in memory, a digital message, a digital image, a video signal or an audio signal, and wherein the True Name is computed using an algorithm that applies a message digest function or a hash function to the contents of the data item.