Method and apparatus for demand based paging algorithm

• US 6,763,382 B1
• Filed: 03/17/2000
• Issued: 07/13/2004
• Est. Priority Date: 03/17/2000
• Status: Expired due to Term

• Current Assignee: Oracle America, Inc. (Oracle Corporation)
• Original Assignee: Sun Microsystems Incorporated (Oracle Corporation)
• Inventors: Gupta, Abhay, Pentyala, Suresh, Balakrishnan, Ravi
• Primary Examiner(s): Jean, Frantz B.
• Assistant Examiner(s): Dinh, Khanh Quang
• Application Number:
  US09/528,092
• Time in Patent Office: 1,579 Days
• Field of Search: 709/203, 709/206, 709/201, 709/223, 709/224, 709/229, 709/227, 709/226, 709/228, 709/232, 709/2
• US Class Current: 709/224
• CPC Class Codes: G06F 16/9574 of access to content, e.g. by caching
• CPC Class Codes: H04L 67/06 specially adapted for file transfer, e.g. file transfer protocol [FTP]
• CPC Class Codes: H04L 67/289 Intermediate processing functionally located close to the data consumer application, e.g. in same machine, in same home or in same sub-network
• CPC Class Codes: H04L 67/568 Storing data temporarily at an intermediate stage, e.g. caching
• CPC Class Codes: H04L 69/329 in the application layer [OSI layer 7]
• CPC Class Codes: H04L 9/40 Network security protocols

Abstract

A method of demand based retrieval of a data file including pages of data, in a network system having a remote host system interconnected to at least one local host system via a first communication link, and one or more end-user systems interconnected to the local host system via a second communication link. A cache buffer is maintained in the local host system for storing a plurality of data pages. Upon receiving a request from an end-user system for the data file, the cache buffer is checked to determine if one or more data pages currently referenced by the request are available therein. If so, one or more of the available data pages are transmitted from the cache buffer to the end user system. Otherwise, the referenced pages are retrieved from the remote host system to the local host system via the first communication link, stored in the cache buffer in the local host system, and transmitted to the end-user system via the second communication link.

Claims

1. In a network system comprising a remote host system interconnected to at least one end-user system via a communication link, a method of retrieving portions of a data file from the remote host system to the end-user system on demand, wherein the data file includes pages of data, comprising:

(a) receiving a request from an end-user system for the data file;

(b) determining one or more data pages currently referenced by the request based upon the location of a scroll bar within an end-user viewing window, adjusted to provide the impression that the entire data file is available to the end-user;

(c) retrieving the one or more referenced data pages from the remote host system; and

(d) transmitting the retrieved data pages to the end user system via the communication link, such that the end-user believes that the entire data file is downloaded to the end-user system and displayed.

2. The method of claim 1, wherein the remote host system contains a plurality of data files each comprising pages of data.

3. The method of claim 2, further comprising the steps of:

(a) providing information to said end-user systems for identifying each of said data files on the remote host system; and

(b) allowing selection of one or more of said identified data files.

4. The method of claim 3, wherein at least one end-user system includes display means, and wherein the step of selecting a data file further includes displaying one or more pages of the data file on said display means.

5. The method of claim 1, wherein the remote host system comprises a central file server system.

6. The method of claim 1, wherein each page of the data file is configurable in size.

7. The method of claim 1, wherein the communication link comprises a plurality of network computers interconnected via transmission lines.

8. The method of claim 1, wherein the second communication link comprises a plurality of network computers interconnected via transmission lines.

9. The method of claim 1, wherein the communication link comprises the Internet.

10. The method of claim 9, wherein the end-user system is configured by a Web browser for downloading data pages from the remote host system and displaying said data pages on a display system.

11. A demand based paging system in a network system comprising a remote host system interconnected to at least one end-user system via a communication link, the demand paging system configured for retrieving portions of a data file in the remote host system to said end-user system on demand, wherein the data file includes pages of data, the demand based paging system comprising:

(a) a request processor configured to receive a request from an end-user system for the data file;

(b) means for determining one or more data pages of the data file currently referenced by the request based upon the location of a scroll bar within an end-user viewing window, adjusted to provide the impression that the entire data file is available to the end-user;

(c) means for retrieving the one or more referenced data pages from the remote host system; and

(d) means for transmitting the retrieved data pages to the end user system via the communication link, such that the end-user believes that the entire data file is downloaded to the end-user system and displayed.

12. The demand based paging system of claim 11, wherein the remote host system contains a plurality of data files each comprising pages of data.

13. The demand based paging system of claim 12, further comprising a user interface for each end-user system, wherein each user interface is configured to (1) provide information to the corresponding end-user system for identifying each of said data files on the remote host system, (2) allow selection of one or more of said identified data files, and (3) and generate requests for the selected data files.

14. The demand based paging system of claim 13, wherein said user interface is further configured to display one or more pages of a selected data file on a display means in said corresponding end-user system.

15. The demand based paging system of claim 11, wherein each page of the data file is configurable in size.

16. The demand based paging system of claim 11, wherein the communication link comprises a plurality of network computers interconnected via transmission lines.

17. In a network system comprising a remote host system interconnected to at least one local host system via a first communication link, and one or more end-user systems interconnected to the local host system via a second communication link, a method of retrieving portions of a data file from the remote host system to said end-user systems on demand, wherein the data file includes pages of data, comprising:

(a) maintaining a cache buffer in the local host system for storing a plurality of data pages;

(b) receiving a request from an end-user system for the data file based upon the location of a scroll bar within an end-user viewing window, adjusted to provide the impression that the entire data file is available to the end-user;

(c) determining whether one or more data pages currently referenced by the request are available in the cache buffer in the local host system; and

(d) if so, transmitting one or more available data pages from the cache buffer to the end user system, otherwise;

(1) retrieving the referenced pages from the remote host system to the local host system via the first communication link, (2) storing the referenced pages in the cache buffer in the local host system, and (3) transmitting the referenced pages from the local host system to the end-user system via the second communication link, such that the end-user believes that the entire data file is downloaded to the end-user system and displayed.

18. The method of claim 17, wherein the remote host system contains a plurality of data files each comprising pages of data.

19. The method of claim 18, further comprising the steps of:

(a) providing information to said end-user systems for identifying each of said data files on the remote host system; and

(b) allowing selection of one or more of said identified data files.

20. The method of claim 19, wherein at least one end-user system includes display means, and wherein the step of selecting a data file further includes displaying one or more pages of the data file on said display means.

21. The method of claim 17, wherein the network system comprises:

(a) a plurality of local host systems interconnected to said remote host system, and

(b) one or more groups of end-user systems corresponding to said local host systems, each of said groups being interconnected to a corresponding local host system.

22. The method of claim 17, wherein the remote host system comprises a central file server system, and wherein the local host system comprises a file cache system.

23. The method of claim 17, wherein each page of the data file is configurable in size.

24. The method of claim 17, wherein the first communication link comprises a plurality of network computers interconnected via transmission lines.

25. The method of claim 17, wherein the second communication link comprises a plurality of network computers interconnected via transmission lines.

26. In a network system comprising a remote host system, one or more local host systems, and a plurality of end-user systems, all capable of being interconnected via the Internet, wherein the end-user systems are grouped into one or more domains each corresponding to a local host system, a method of retrieving portions of a data file from the remote host system to an end-user system on demand, wherein the data file includes pages of data, comprising:

(a) maintaining a cache buffer in each local host system for storing a plurality of data pages;

(b) receiving requests from one or more end-user systems in a domain for the data file based upon the location of a scroll bar within an end-user viewing window, adjusted to provide the impression that the entire data file is available to the end-user; and

(c) for each request performing steps including;

(1) determining whether one or more data pages currently referenced by the request are available in the cache buffer of the local host system corresponding to said domain; and

(2) if so, transmitting one or more available data pages from the cache buffer to the requesting end user system, otherwise;

(i) retrieving the referenced pages from the remote host system to the local host system, (ii) storing the referenced pages in the cache buffer in the local host system, and (iii) transmitting the referenced pages from the local host system to the requesting end-user system, such that the end-user believes that the entire data file is downloaded to the end-user system and displayed.

27. The method of claim 26, wherein the remote host system contains a plurality of data files each comprising pages of data.

28. The method of claim 27, further comprising the steps of:

(a) providing information to said end-user systems for identifying each of said data files on the remote host system; and

(b) allowing selection of one or more of said identified data files.

29. The method of claim 28, wherein at least one end-user system includes display means, and wherein the step of selecting a data file further includes displaying one or more pages of the data file on said display means.

30. The method of claim 26, wherein the remote host system comprises a central file server system, and wherein each local host system comprises a domain cache server.

31. The method of claim 26, wherein each end-user system is configured by a Web browser for downloading data pages from a local host system and displaying said data pages on a display system.