System and method for optimizing content retrieval over a data network

• US 20090144395A1
• Filed: 06/17/2005
• Published: 06/04/2009
• Est. Priority Date: 06/17/2005
• Status: Active Grant

• Current Assignee: Microsoft Technology Licensing LLC (Microsoft Corporation)
• Original Assignee: Danger Incorporated (Microsoft Corporation)
• Inventors: DeSalvo, Christopher J.
• Granted Patent: US 7,613,780 B2
• Time in Patent Office: Days
• US Class Current: 709/219
• CPC Class Codes: G06F 16/9574 of access to content, e.g. by caching

Abstract

A method is described comprising: receiving a request for content stored on a network site from a data processing device, the request including and address for the content and first version information usable to identify a version of the content previously-downloaded to the data processing device; transmitting a first request to the network site on behalf of the data processing device, the first request including the address of the content but requesting only second version information related to the content, the second version information identifying a current version of the content stored on the network site; comparing the first version information with the second version information to determine whether the current version of the content stored on the data processing device is the latest version; transmitting an indication to the client that the client has the latest version of the content if the first version information matches the second version information; if the first version information does not match the second version information, then transmitting a second request to the network site requesting the latest version of the content and forwarding the latest version of the content to the data processing device.

Claims

1. A method comprising:

receiving a request for content stored on a remote network site from a data processing device, the request including an address for the content and first version information usable to identify a version of the content previously-transmitted to the data processing device;

transmitting a first request to the network site on behalf of the data processing device, the first request including the address of the content but requesting only second version information related to the content, the second version information identifying a current version of the content stored on the network site;

comparing the first version information with the second version information to determine whether the current version of the content stored on the data processing device is a latest version;

transmitting an indication to the client that the client has the latest version of the content if the first version information matches the second version information;

if the first version information does not match the second version information, then

transmitting a second request to the network site requesting the latest version of the content,

converting the latest version of the content based on the processing capabilities of the data processing device; and

forwarding the converted latest version of the content to the data processing device; and

determining if the behaviour of the network site is known;

if the network site corredponds to a first type of behavior, then initially transmitting the first request to the network site; and

if the network site corresponds to a second type of behavior, then refraining from transmitting the first request and instead initially transmitting the second request to the network site.

2. The method as in claim 1 wherein the request for content comprises a request for a particular Web page, wherein transmitting the first request to the network site comprises transmitting an HTTP HEAD request for a header of the Web page, the header containing the second version information, and wherein the second request to the network site comprises an HTTP GET request for the entire Web page.

7. The method as in claim 1 wherein comparing the first version information to the second version information comprises:

determining if ETag fields in the first version information and the second version information match if they exist;

wherein, if no ETags exist, then determining if last modified date/time fields in the first version information and the second version information match if they exist; and

wherein, if no last modified date/time fields exist, then determining if content length fields in the first version information and the second version information match.

3. (canceled)

4. The method as in claim 3 wherein the first type of behavior is that the network site is operating improperly with respect to a designated network protocol, and wherein the second type of behavior is that the network site is operating properly and in compliance with the designated network standard.

5. The method as in claim 4 wherein the network standard comprises the hypertext transport protocol (“

HTTP”

) and wherein operating improperly comprises the network site responding with a complete Web page even though the client has the latest version of the content.

6. The method as in claim 5 wherein operating properly comprises the network site responding with an HTTP 304 response when the version requested is the same as the version stored at the network site.

8. A system comprising a memory for storing program code and a processor for processing the program code, the program code causing the processor to perform the operations of:

receiving a request for content stored on a network site from a data processing device, the request including and address for the content and first version information usable to identify a version of the content previously-downloaded to the data processing device;

transmitting a first request to the network site on behalf of the data processing device, the first request including the address of the content but requesting only second version information related to the content, the second version information identifying a current version of the content stored on the network site;

comparing the first version information with the second version information to determine whether the current version of the content stored on the data processing device is the latest version;

transmitting an indication to the client that the client has the latest version of the content if the first version information matches the second version information;

if the first version information does not match the second version information, then

transmitting a second request to the network site requesting the latest version of the content,

converting the latest version of the content based on the processing capabilities of the data processing device; and

forwarding the converted latest version of the content to the data processing device; and

determining if the behavior of the network site is known;

if the network site corresponds to a first type of behavior, then initially transmitting the first request to the network site; and

if the network site corresponds to a second type of behavior, then refraining from transmitting the first request and instead initially transmitting the second request to the network site.

9. The system as in claim 8 wherein the request for content comprises a request for a particular Web page, wherein transmitting the first request to the network site comprises transmitting an HTTP HEAD request for a header of the Web page, the header containing the second version information, and wherein the second request to the network site comprises an HTTP GET request for the entire Web page.

14. The system as in claim 8 wherein comparing the first version information to the second version information comprises:

determining if ETag fields in the first version information and the second version information match if they exist;

wherein, if no ETags exist, then determining if last modified date/time fields in the first version information and the second version information match if they exist; and

wherein, if no last modified date/time fields exist, then determining if content length fields in the first version information and the second version information match.

21. The machine-readable medium as in claim 8 wherein comparing the first version information to the second version information comprises:

determining if ETag fields in the first version information and the second version information match if they exist;

wherein, if no ETags exist, then determining if last modified date/time fields in the first version information and the second version information match if they exist; and

wherein, if no last modified date/time fields exist, then determining if content length fields in the first version information and the second version information match.

10. (canceled)

11. The system as in claim 10 wherein the first type of behavior is that the network site is operating improperly with respect to a designated network protocol, and wherein the second type of behavior is that the network site is operating properly and in compliance with the designated network standard.

12. The system as in claim 11 wherein the network standard comprises the hypertext transport protocol (“

HTTP”

) and wherein operating improperly comprises the network site responding with a complete Web page even though client has the latest version of the content.

13. The system as in claim 12 wherein operating properly comprises the network site responding with an HTTP 304 response when the version requested is the same as the version stored at the network site.

15. A machine-readable medium having program code stored thereon which, when executed by a processor, causes the processor to perform the operations of:

receiving a request for content stored on a network site from a data processing device, the request including and address for the content and first version information usable to identify a version of the content previously-downloaded to the data processing device;

transmitting a first request to the network site on behalf of the data processing device, the first request including the address of the content but requesting only second version information related to the content, the second version information identifying a current version of the content stored on the network site;

comparing the first version information with the second version information to determine whether the current version of the content stored on the data processing device is the latest version;

transmitting an indication to the client that the client has the latest version of the content if the first version information matches the second version information;

if the first version information does not match the second version information, then

transmitting a second request to the network site requesting the latest version of the content,

converting the latest version of the content based on the processing capabilities of the data processing device; and

forwarding the converted latest version of the content to the data processing device; and

determining if the behavior of the network site is known;

if the network site corresponds to a second type of behavior, then refraining from transmitting the first request to the network site; and

if the network site corredponds to a second type of behavior, then refraining from transmitting the first request and instead initially transmitting the second request to the network site.

16. The machine-readable medium as in claim 15 wherein the request for content comprises a request for a particular Web page, wherein transmitting the first request to the network site comprises transmitting an HTTP HEAD request for a header of the Web page, the header containing the second version information, and wherein the second request to the network site comprises an HTTP GET request for the entire Web page.

17. (canceled)

18. The machine-readable medium as in claim 17 wherein the first type of behavior is that the network site is operating improperly with respect to a designated network protocol, and wherein the second type of behavior is that the network site is operating properly and in compliance with the designated network standard.

19. The machine-readable medium as in claim 18 wherein the network standard comprises the hypertext transport protocol (“

HTTP”

) and wherein operating improperly comprises the network site responding with a complete Web page even though the client has the latest Version of the content.

20. The machine-readable medium as in claim 19 wherein operating properly comprises the network site responding with an HTTP 304 response when the version requested is the same as the version stored at the network site.