Internet computer system with methods for dynamic filtering of hypertext tags and content

• US 6,122,657 A
• Filed: 03/11/1997
• Issued: 09/19/2000
• Est. Priority Date: 02/04/1997
• Status: Expired due to Term

• Current Assignee: McAfee, LLC
• Original Assignee: Network Associates, Inc.
• Inventors: Hoffman, Gene Jr., Elrod, Mark B.
• Primary Examiner(s): Rinehart, Mark H.
• Assistant Examiner(s): VU, THONG H
• Application Number:
  US08/815,164
• Time in Patent Office: 1,288 Days
• Field of Search: 395/200.32, 395/615, 395/761, 395/200.57, 395/762, 707/8, 707/512, 707/200, 707/513, 235/472, 709/218, 709/200, 709/217, 709/201, 705/14, 704/276
• US Class Current: 709/201
• CPC Class Codes: G06F 16/957 Browsing optimisation, e.g. caching or content distillation
• CPC Class Codes: G06F 16/9577 Optimising the visualization of content, e.g. distillation of HTML documents
• CPC Class Codes: H04L 67/02 based on web technology, e.g. hypertext transfer protocol [HTTP]
• CPC Class Codes: H04L 9/40 Network security protocols

Abstract

An Internet computer system with methods for dynamic filtering of hypertext tags and content is described. The system includes one or more Web clients, each operating a Web browser (e.g., Netscape Navigator or Microsoft Internet Explorer) with an Internet connection to one or more Web servers. Each client includes, interposed between its browser and communication layer, a Filter module of the present invention which traps and processes all communications between the browser and the communication layer. The Filter module, which implements client-side methodology at each individual Web client for dynamic filtering of hypertext tags and content, includes an output stream, a processing loop, a Filter method, and an input stream. During system operation, the Web browser generates multiple requests for retrieving content. More particularly, particular content is retrieved by a fetch or GET command (e.g., using HTTP protocol) transmitted to a target server from the client-side communication layer (e.g., Winsock driver). The command is, however, trapped by the Filter module. The "real" request or command is at this point processed by the Filter method of the Filter module. Accordingly, the system can modify the command, delete the command, synthesize new commands, or pass through unchanged the existing command. In an exemplary embodiment, the Filter method provides handlers for specific processing of various HTML (Hypertext Markup Language) tags, all operating according to user-configurable filtering preferences.

Claims

1. In a computer system having a browser for retrieving information from servers across a remote connection, said information including content and tag-based commands, said tag-based commands affecting display of content at the browser, the tag-based commands each being associated with at least one tag for identifying a particular command, an improved method for processing content and tag-based commands by selectively trapping commands, the method comprising:

receiving at the browser user-configurable settings indicating how particular types of tag-based command are to be processed by the browser;

receiving a user request at the browser for retrieval of information of interest from a particular server;

in response to said request, sending a fetch request from the browser to the particular server, for retrieving said information of interest;

in response to said fetch request, receiving at the browser a stream of information from the particular server, said stream of information including tag-based commands; and

selectively trapping each command as each command is received in said stream of information, by performing substeps of;

(i) identifying the command by type, and

(ii) based on the identified type for the command, processing the command according to said user-configurable settings by performing a selected one of modifying the command, deleting the command, replacing the command with a new command, or passing the command through to the browser unchanged.

2. The method of claim 1, wherein said browser comprises a Web browser for rendering HTML (Hypertext Markup Language) documents.

3. The method of claim 2, wherein said tag-based commands in said stream of information include HTML tags.

4. The method of claim 3, wherein some of the HTML tags comprise tag pairs, each tag pair specifying a particular action for content delimited by the tag pair.

5. The method of claim 1, wherein said deleting the command in substep (ii) includes deleting any content associated with the deleted command.

6. The method of claim 1, wherein said substep (ii) comprises filtering retrieval of any images larger than a user-configurable maximum size by deleting image tags for any images identified as being larger than said maximum size, thereby blocking retrieval of images larger than said user-configurable maximum size.

7. The method of claim 6, wherein said substep (ii) includes querying the particular server for determining a size for an image whose image tag is being processed.

8. The method of claim 6, wherein said substep (ii) includes determining content for an image whose image tag is being processed.

9. The method of claim 8, wherein said determining content for an image whose image tag is being processed includes determining whether the image resides at an ad site.

10. The method of claim 8, wherein said determining content for an image whose image tag is being processed includes determining a signature for the image and comparing the signature against a list of signatures for known images.

11. The method of claim 10, wherein said determining a signature includes computing a checksum for the image.

12. The method of claim 11, wherein said checksum comprises a Cyclic Redundancy Checksum (CRC) computed value.

13. The method of claim 1, wherein said deleting the command in substep (ii) includes deleting executable script according to said user-configurable settings.

14. The method of claim 1, wherein said remote connection comprises an Internet connection.

15. The method of claim 1, wherein user-configurable settings include a user setting to block display of ads at the browser.

16. In a computer system having a browser for retrieving information from servers across a remote connection, said information including content and HTML (Hypertext Markup Language) tags, said HTML tags affecting display of content at the browser, a method for blocking display of ads at the browser, the method comprising:

receiving a user request at the browser for retrieval of a Web page from a particular Web server;

in response to said request, sending a fetch request from the browser to the particular Web server, for retrieving the Web page;

in response to said fetch request, receiving at the browser a stream of information from the particular Web server, said stream of information including HIML tags; and

selectively trapping HTML tags as HTML tags are received with said stream of information at the browser, by performing substeps of;

(i) identifying any HTML tags which comprise image tags,

(ii) determining whether any image tags specify retrieval of content which comprises ad images, and

(ii) deleting all image tags which specify retrieval of content which comprises ad images, such that the Web page is displayed at the browser without displaying ads.

17. The method of claim 16, wherein said determining whether any image tags specify retrieval of content which comprises ad images includes determining whether any image tags specify retrieval of content from an ad site.

18. The method of claim 17, wherein said determining whether any image tags specify retrieval of content which comprises ad images includes determining whether any image tags specify retrieval of content from an ad subdirectory of the particular Web server.

19. The method of claim 16, wherein said determining whether any image tags specify retrieval of content which comprises ad images includes determining a signature for each image and comparing the signature against a list of signatures for known ad images.

20. The method of claim 19, wherein said signature comprises a checksum.

21. An Internet computer system comprising:

a client computer having a communication layer providing the client computer with connections to remote servers on the Internet;

a Web browser for retrieving information from the remote servers, by issuing commands to the communication layer in response to user input and in response to markup language command tags parsed from Web pages retrieved from the remote servers; and

a filter, operably interposed between the browser and the communication layer, comprising;

means for trapping command tags parsed from retrieved Web pages, and

means, responsive to user-configurable settings, for filtering said trapped command tags, by modifying or deleting selected command tags.

22. The system of claim 21, wherein said means for filtering includes:

filter logic for deleting command tags of a certain type.

23. The system of claim 21, wherein said means for filtering includes:

filter logic for modifying command tags of a certain type.

24. The system of claim 21, wherein said means for filtering includes:

filter logic for passing through unchanged to the browser command tags of a certain type.

25. The system of claim 21, wherein said communication layer comprises a Transmission Control Protocol/Internet Protocol (TCP/IP) communication driver.

26. The system of claim 21, wherein said client computer communicates with said remote servers via Hypertext Transport Protocol (HTTP).

27. The system of claim 21, wherein said means for trapping command tags includes:

means for trapping image command tags; and

means for determining whether images specified by trapped image command tags should be blocked.

28. The system of claim 27, wherein said means for determining whether images specified by trapped image command tags should be blocked includes:

means for blocking images which comprise advertising material.

29. The system of claim 27, wherein said means for determining whether images specified by trapped image command tags should be blocked includes:

means for blocking any image having a size which exceeds a user-specified maximum image size.

30. The system of claim 27, wherein said means for determining whether images specified by trapped image command tags should be blocked includes:

means for computing a signature for individual images; and

means for blocking those images having signatures which match signatures stored for unwanted images.

31. The system of claim 30, wherein each signature comprises a computed checksum value for an individual image.

32. The system of claim 21, wherein said markup language command tags comprise Hypertext Markup Language (HTML) command tags.

33. The system of claim 21, wherein said means for trapping command tags includes:

means for trapping JavaScript command tags; and

means for determining whether applets specified by trapped JavaScript command tags should be blocked.

34. The system of claim 21, wherein said means for trapping command tags includes:

means for trapping command tags affecting display of text; and

means for determining based on user-specified settings whether trapped JavaScript command tags affecting display of text should be blocked.

35. The system of claim 34, wherein said command tags affecting display of text include "blinking text" command tags.