System and method for performing entity tag and cache control of a dynamically generated object not identified as cacheable in a network

• US 20060195660A1
• Filed: 12/30/2005
• Published: 08/31/2006
• Est. Priority Date: 01/24/2005
• Status: Active Grant

• Current Assignee: Citrix Systems, Inc. (Cloud Software Group)
• Original Assignee: Citrix Systems, Inc. (Cloud Software Group)
• Inventors: Bhushan K R, Bharath, Soni, Ajay, Kailash, Kailash, Sinha, Rajiv, Kumar, Anil, Khemani, Prakash, Annamalaisami, Saravana, Sundarrajan, Prabakar
• Granted Patent: US 7,849,269 B2
• Time in Patent Office: Days
• US Class Current: 711/118
• 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]

Abstract

The present invention is directed towards a method and system for modifying by a cache responses from a server that do not identify a dynamically generated object as cacheable to identify the dynamically generated object to a client as cacheable in the response. In some embodiments, such as an embodiment handling HTTP requests and responses for objects, the techniques of the present invention insert an entity tag, or “etag” into the response to provide cache control for objects provided without entity tags and/or cache control information from an originating server. This technique of the present invention provides an increase in cache hit rates by inserting information, such as entity tag and cache control information for an object, in a response to a client to enable the cache to check for a hit in a subsequent request.

Claims

1. A method of using an entity tag for caching a dynamically generated object not identified as cacheable, the method comprising the steps of:

(a) receiving, by a cache, a response to a request of a client for a dynamically generated object from an originating server, the dynamically generated object identified as not cacheable,

(b) generating, by the cache, an entity tag for the dynamically generated object stored in the cache;

(c) modifying, by the cache, the response to include the generated entity tag; and

(d) transmitting, by the cache, to the client the modified response identifying the dynamically generated object as cacheable.

2. The method of claim 1, wherein the response received from the originating server does not comprise an entity tag.

3. The method of claim 1, comprising modifying, by the cache, the response to identify a duration for the client to cache the dynamically generated object.

4. The method of claim 1, comprising modifying, by the cache, the response to indicate to the client to store the response and serve the response after checking if the dynamically generated object has changed with one of the cache or the originating server.

5. The method of claim 1, wherein the response from the originating server does not have cache control information for the dynamically generated object, and the cache modifies the response transmitted to the client to include cache control information.

6. The method of claim 1, comprising generating, by the cache, a number for the entity tag.

7. The method of claim 1, comprising storing, by the cache, the generated entity tag with the dynamically generated object.

8. The method of claim 7, comprising storing, by the cache, cache control information with the dynamically generated object.

9. The method of claim 8, comprising serving, by the cache, the cached dynamically generated object with the generated entity tag and cache control information.

10. The method of claim 1, comprising operating the cache on one of an appliance, network device or computing device.

11. The method of claim 1, wherein one of the request or the response comprises HyperText Markup Language (HTML).

12. The method of claim 11, comprising modifying, by the cache, the response to include an etag header identifying the generated entity tag.

13. The method of claim 1 comprising modifying, by the cache, the response to include a cache-control header.

14. The method of claim 11, comprising receiving, by the cache, from the client a second request having an If-None-Match header, and in response to the second request, comparing the etag value associated with the If-None-Match header to the entity tag stored in the cache with the dynamically generated object.

15. The method of claim 14, comprising transmitting, by the cache, to the client a not modified response to the second request if the etag value matches the entity tag.

16. The method of claim 14, comprising transmitting, by the cache, to the client an updated dynamically generated object with a second entity tag if the etag value does not match the entity tag.

17. A system for using of using an entity tag for caching a dynamically generated object identified as not cacheable, the system comprising:

means for receiving, by a cache, a response to a request of a client for a dynamically generated object from an originating server, the dynamically generated object identified as not cacheable,

means for generating, by the cache, an entity tag for the dynamically generated object stored in the cache;

means for modifying, by the cache, the response to include the generated entity tag; and

means for transmitting, by the cache, to the client the modified response identifying the dynamically generated object as cacheable.

18. The system of claim 17, wherein the response received from the originating server does not comprise an entity tag.

19. The system of claim 17, comprising means for modifying, by the cache, the response to identify a duration for the client to cache the dynamically generated object.

20. The system of claim 17, comprising means for modifying, by the cache, the response to indicate to the client to store the response and serve the response after checking if the dynamically generated object has changed with one of the cache or the originating server.

21. The system of claim 17, wherein the response from the originating server does not have cache control information for the dynamically generated object, and the cache modifies the response transmitted to the client to include cache control information.

22. The system of claim 17, comprising means for generating, by the cache, a number for the entity tag.

23. The system of claim 17, comprising means for storing, by the cache, the generated entity tag with the dynamically generated object.

24. The system of claim 17, comprising means for storing, by the cache, cache control information with the dynamically generated object.

25. The system of claim 24, comprising means for serving, by the cache, the cached dynamically generated object with the generated entity tag and cache control information.

26. The system of claim 17, comprising means for operating the cache on one of an appliance, network device or computing device.

27. The system of claim 17, wherein one of the request or the response comprises Hypertext Markup Language (HTML).

28. The system of claim 27, comprising means for modifying, by the cache, the response to include an etag header identifying the generated entity tag.

29. The system of claim 27, comprising means for modifying, by the cache, the response to include a cache-control header.

30. The system of claim 27, comprising means for comprising receiving, by the cache, from the client a second request having a If-None-Match header, and in response to the second request, comparing the etag value associated with the If-None-Match header to the entity tag stored in the cache with the dynamically generated object.

31. The system of claim 30, comprising means for transmitting, by the cache, to the client a not modified response to the second request if the etag value matches the entity tag.

32. The system of claim 30, comprising means for transmitting, by the cache, to the client an updated dynamically generated object with a second entity tag if the etag value does not match the entity tag.