Proxy caching in a photosharing peer-to-peer network to improve guest image viewing performance

• US 20060010225A1
• Filed: 08/25/2004
• Published: 01/12/2006
• Est. Priority Date: 03/31/2004
• Status: Active Grant

• Current Assignee: Ikorongo Technology, LLC (Concert Technology Corporation)
• Original Assignee: Qurio Holdings Incorporated
• Inventors: Issa, Ai
• Granted Patent: US 8,234,414 B2
• Time in Patent Office: Days
• US Class Current: 709/217
• CPC Class Codes: G06F 16/9574 of access to content, e.g. by caching
• CPC Class Codes: H04L 63/02 for separating internal from external traffic, e.g. firewalls
• CPC Class Codes: H04L 67/02 based on web technology, e.g. hypertext transfer protocol [HTTP]
• CPC Class Codes: H04L 67/104 Peer-to-peer [P2P] networks
• CPC Class Codes: H04L 67/1063 Discovery through centralising entities
• CPC Class Codes: H04L 67/108 characterised by resources being split in blocks or fragments
• CPC Class Codes: H04L 67/568 Storing data temporarily at an intermediate stage, e.g. caching

Abstract

The present invention provides a method and system for serving an image stored in the peer computer to a requesting computer in a network photosharing system in which the peer computer is coupled to a photosharing system server. Aspects of the invention include caching copy of the image in the photosharing server; and in response to the photosharing server receiving a request from the requesting computer to view the image stored in the peer computer, transmitting the cached image from the photosharing server to the requesting computer, thereby avoiding the need to transfer the image from the peer computer to the photosharing server for each request to view the image.

Claims

1. In a network photosharing system having at least one peer computer coupled to a photosharing system server, a method for serving an image stored in the peer computer to a requesting computer, comprising:

(a) caching copy of the image in the photosharing server;

(b) in response to the photosharing server receiving a request from the requesting computer to view the image stored in the peer computer, sending a request from the photosharing server to the peer computer to determine if the image stored on the peer computer has been modified;

(c) if a response from the peer computer indicates that the image has not been modified, transmitting the cached image from the photosharing server to the requesting computer; and

(d) if the image has been modified, caching a copy of the modified image on the photosharing server, and transmitting the modified image from the photosharing server to the requesting computer.

2. The method of claim 1 wherein step (b) further includes:

sending the request to the peer computer as an HTTP request.

3. The method of claim 2 wherein step (b) further includes:

sending an HTTP If-Modified-Since header and a timestamp of the cached image as the request.

4. The method of claim 3 wherein step (b) further includes:

in response to the peer computer receiving the HTTP request,

(i) comparing the timestamp for the cached image with a timestamp of the image stored on the peer computer;

(ii) if the timestamps are different, responding by transferring the modified image to the photosharing server; and

(iii) if the timestamps are not different, sending the response indicating that the image has not been modified.

5. The method of claim 1 wherein step (a) further includes:

(i) determining if the image stored in the peer computer is also stored in the photosharing server; and

(ii) if the image is not stored in the photosharing server, transferring a copy of the image to the photosharing server for storage.

6. The method of claim 5 wherein step (a) is performed a first time the image is requested.

7. The method of claim 6 wherein step (a) is performed during a synchronization process between the photosharing server and the peer server.

8. The method of claim 7 further comprising:

once the synchronization process is invoked, uploading timestamps of the images stored on the peer server to the photosharing server, and comparing the uploaded timestamps to the timestamps for the images in the cache to determine if the cached images are current and whether or missing images in the cache.

9. The method of claim 8 further comprising:

sending a request from the photosharing server to the peer server for any images identified as being modified or missing, thereby synchronizing the images cached on the photosharing server with the images stored on the peer server.

10. The method of claim 9 further comprising:

performing background synchronization.

11. The method of claim 9 wherein the photosharing server includes the synchronization server for performing the timestamp comparisons.

12. The method of claim 1 wherein the photosharing server comprises a proxy server that provides the requesting computer HTTP access to the peer server when located behind a firewall.

13. A network photosharing system having at least one peer computer coupled to a photosharing system server, comprising:

(a) means for caching copy of the image in the photosharing server;

(b) means responsive to the photosharing server receiving a request from the requesting computer to view the image stored in the peer computer, sending a request from the photosharing server to the peer computer to determine if the image stored on the peer computer has been modified;

(c) means for transmitting the cached image from the photosharing server to the requesting computer if a response from the peer computer indicates that the image has not been modified; and

(d) means for caching a copy of the modified image on the photosharing server if the image has been modified, and for transmitting the modified image from the photosharing server to the requesting computer.

14. The system of claim 13 wherein the means for receiving the request sends the request to the peer computer as an HTTP request.

15. The system of claim 14 wherein the means for receiving the request sends an HTTP If-Modified-Since header and a timestamp of the cached image as the request.

16. The system of claim 15 wherein the means for receiving the request is responsive to the peer computer receiving the HTTP request for,

(i) comparing the timestamp for the cached image with a timestamp of the image stored on the peer computer;

(ii) if the timestamps are different, responding by transferring the modified image to the photosharing server; and

(iii) if the timestamps are not different, sending the response indicating that the image has not been modified.

17. The system of claim 13 wherein the caching means further includes means for:

(i) determining if the image stored in the peer computer is also stored in the photosharing server; and

(ii) if the image is not stored in the photosharing server, transferring a copy of the image to the photosharing server for storage.

18. The system of claim 17 wherein the image is cached a first time the image is requested.

19. The system of claim 17 wherein the image is cached during a synchronization process between the photosharing server and the peer server.

20. The system of claim 19 wherein once the synchronization process is invoked, timestamps of the images stored on the peer server are uploaded to the photosharing server and compared the uploaded timestamps to the timestamps for the images in the cache to determine if the cached images are current and whether or missing images in the cache.

21. The system of claim 20 wherein a request is sent from the photosharing server to the peer server for any images identified as being modified or missing, thereby synchronizing the images cached on the photosharing server with the images stored on the peer server.

22. The system of claim 21 wherein synchronization is performed in the background.

23. The system of claim 21 wherein the photosharing server includes the synchronization server for performing the timestamp comparisons.

24. The system of claim 13 wherein the photosharing server comprises a proxy server that provides the requesting computer HTTP access to the peer server when located behind a firewall.

25. A computer-readable medium containing program instructions for serving an image stored in the peer computer to a requesting computer in a network photosharing system where the peer computer is coupled to a photosharing system server, the instructions for:

(a) caching copy of the image in the photosharing server;

(b) in response to the photosharing server receiving a request from the requesting computer to view the image stored in the peer computer, sending a request from the photosharing server to the peer computer to determine if the image stored on the peer computer has been modified;

(c) if a response from the peer computer indicates that the image has not been modified, transmitting the cached image from the photosharing server to the requesting computer; and

(d) if the image has been modified, caching a copy of the modified image on the photosharing server, and transmitting the modified image from the photosharing server to the requesting computer.

26. The computer-readable medium of claim 25 wherein instruction (b) further includes:

sending the request to the peer computer as an HTTP request.

27. The computer-readable medium of claim 26 wherein instruction (b) further includes:

sending an HTTP If-Modified-Since header and a timestamp of the cached image as the request.

28. The computer-readable medium of claim 27 wherein instruction (b) further includes:

in response to the peer computer receiving the HTTP request,

(i) comparing the timestamp for the cached image with a timestamp of the image stored on the peer computer;

(ii) if the timestamps are different, responding by transferring the modified image to the photosharing server; and

(iii) if the timestamps are not different, sending the response indicating that the image has not been modified.

29. The computer-readable medium of claim 25 wherein instruction (a) further includes:

(i) determining if the image stored in the peer computer is also stored in the photosharing server; and

(ii) if the image is not stored in the photosharing server, transferring a copy of the image to the photosharing server for storage.

30. The computer-readable medium of claim 29 wherein instruction (a) is performed a first time the image is requested.

31. The computer-readable medium of claim 30 wherein instruction (a) is performed during a synchronization process between the photosharing server and the peer server.

32. The computer-readable medium of claim 31 further comprising:

once the synchronization process is invoked, uploading timestamps of the images stored on the peer server to the photosharing server, and comparing the uploaded timestamps to the timestamps for the images in the cache to determine if the cached images are current and whether or missing images in the cache.

33. The computer-readable medium of claim 32 further comprising:

sending a request from the photosharing server to the peer server for any images identified as being modified or missing, thereby synchronizing the images cached on the photosharing server with the images stored on the peer server.

34. The computer-readable medium of claim 33 further comprising:

performing background synchronization.

35. The computer-readable medium of claim 33 wherein the photosharing server includes the synchronization server for performing the timestamp comparisons.

36. The computer-readable medium of claim 25 wherein the photosharing server comprises a proxy server that provides the requesting computer HTTP access to the peer server when located behind a firewall.