Method, system, and computer program product to redirect requests from content servers to load distribution servers and to correct bookmarks

• US 7,177,901 B1
• Filed: 03/27/2000
• Issued: 02/13/2007
• Est. Priority Date: 03/27/2000
• Status: Expired due to Fees

• Current Assignee: International Business Machines Corporation
• Original Assignee: International Business Machines Corporation
• Inventors: Dutta, Rabindranath
• Primary Examiner(s): NGUYEN, THU HA T
• Application Number:
  US09/534,592
• Time in Patent Office: 2,514 Days
• Field of Search: 709/105, 709/200, 709/217, 709/218, 709223-227, 709/229, 709/238, 709/245, 709201-203, 713/201, 713/169, 713/170, 713/162, 713/200, 707/10, 707/2, 707/9, 370/237, 718100-105
• US Class Current: 709/203
• CPC Class Codes: H04L 67/1001 for accessing one among a plurality of replicated servers
• CPC Class Codes: H04L 67/1008 based on parameters of servers, e.g. available memory or workload monitoring of computer activity G06F11/30

Abstract

In a system where a central load distribution server at a publicized URL redirects requests for files to a number of content servers holding identical content on the basis of dynamically determined capacity utilization of those servers, clients are prevented from directly accessing one of the content servers without first being redirected from the central load distribution server. In the event that a client attempts to access one of the content servers without first having been redirected there from the load distribution server, the client is redirected to a page containing a notice of the error, then redirected yet again to the load distribution server. For browsers in which bookmark lists may be edited by the user, facilities are provided for correcting the bookmark entry that brought the user to the protected content server rather than to the central load distribution server. In this way, the tendency of users to unintentionally or intentionally circumvent traffic routing algorithms is substantially reduced and the risk of any one content server being overwhelmed with traffic is likewise reduced.

Claims

1. A method of preventing a client from directly contacting a content server that is protected by a load distribution server from an overload of traffic, comprising:

receiving, at said content server, a request by the client for a file from said content server;

determining, at said content server, whether said request originated as a reference from the load distribution server and determining whether said request originated as a reference from said content server itself;

responsive to determining that said request originated as a reference from a set consisting of the load distribution server and said content server, said content server providing the requested file to the client;

determining whether said request received from said content server originated as a reference from neither of the set consisting of the load distribution server and said content server; and

responsive to determining that the client'"'"'s request to receive the file from said content server originated as the reference from neither of the set consisting of the load distribution server and said content server, sending to the client a file requesting that the client contact the load distribution server, such that the client is prevented from directly accessing the file at said content server without first being redirected from the load distribution server.

2. The method of claim 1, further comprising:

including in the file requesting that the client contact the load distribution server a means by which the client may directly contact the load distribution server through an initiative of a user of the client.

3. The method of claim 1, further comprising:

offering in the file requesting that the client contact the load distribution server a means to update a bookmark file to include the load distribution server.

4. The method of claim 3, wherein said set consisting of the load distribution server and said content server is a first set and said method further comprises:

offering in one of a second set consisting of the file requesting that the client contact the load distribution server and the means to update the client'"'"'s bookmark file to include the load distribution server a means to update the bookmark file to exclude said content server.

5. The method of claim 1, wherein the step of determining whether said client'"'"'s request to receive said file from said content server originated as a reference from said content server further comprises determining, based on the recently of a time stamp contained within a client'"'"'s request to receive a file from said content server, whether said client'"'"'s request to receive said file from said content server originated as a reference from said content server.

6. The method of claim 1, further comprising:

including in the file requesting that the client contact the load distribution server a means by which to allow a user of the client sufficient time to read and react to the file requesting that the user of the client contact the load distribution server before contact with the load distribution server is established without intervention of the user.

7. A machine-readable storage medium having a plurality of instructions readable by a machine embodied therein, wherein said plurality of instructions, when processed by said machine, causes said machine to perform a method for preventing a client from directly contacting a content server that is protected by a load distribution server from an overload of traffic, said method comprising:

receiving, at said content server, a request by the client for a file from said content server;

determining, at said content server, whether said request originated as a reference from the load distribution server and determining whether said request originated as a reference from said content server itself;

responsive to determining that the request originated as a reference from a set consisting of the load distribution server and said content server, said content server providing the requested file to the client;

determining whether said request received from said content server originated as a reference from neither of the set consisting of the load distribution server and said content server; and

responsive to determining that the client'"'"'s request to receive the file from said content server originated as the reference from neither of the set consisting of the load distribution server and said content server, sending to the client a file requesting that the client contact the load distribution server, such that the client is prevented from directly accessing the file at said content server without first being redirected from the load distribution server.

8. The machine-readable storage medium of claim 7, said method further comprising:

including in the file requesting that the client contact the load distribution server a means by which the client may directly contact the load distribution server through an initiative of a user of the client.

9. The machine-readable storage medium of claim 7, said method further comprising:

offering in the file requesting that the client contact the load distribution server a means to update a bookmark file to include the load distribution server.

10. The machine-readable storage medium of claim 9 wherein:

said set consisting of the load distribution server and said content server is a first set and said method further comprises;

offering in one of a second set consisting of the file requesting that the client contact the load distribution server and the means to update the client'"'"'s bookmark file to include the load distribution server a means to update the bookmark file to exclude said content server.

11. The machine-readable storage medium of claim 7, wherein the step of determining whether said client'"'"'s request to receive said file from said content server originated as a reference from said content server further comprises determining, based on the recently of a time stamp contained within a client'"'"'s request to receive the file from said content server, whether said client'"'"'s request to receive said file from said content server originated as a reference from the said content server.

12. The machine-readable storage medium of claim 7, said method further comprising:

including in the file requesting that the client contact the load distribution server a means by which to allow a user of the client sufficient time to read and react to the file requesting that the user of the client contact the load distribution server before contact with the load distribution server is established without intervention of the user.

13. A system for preventing a client from directly contacting a content server that is protected by a load distribution server from an overload of traffic, comprising:

means for receiving, at said content server, a request by the client for a file from said content server;

means for determining, at said content server, whether said request originated as a reference from the load distribution server and for determining whether said request originated as a reference from said content server itself;

means for, responsive to determining that the request originated as a reference from a set consisting of the load distribution server and said content server, for providing the requested file to the client;

means for determining whether said request received from said content server originated as a reference from neither of the set consisting of the load distribution server and said content server; and

means for, responsive to determining that the client'"'"'s request to receive the file from said content server originated as the reference from neither of the set consisting of the load distribution server and said content server, sending to the client a file requesting that the client contact the load distribution server, such that the client is prevented from directly accessing the file at said content server without first being redirected from the load distribution server.

14. The system of claim 13, further comprising:

means for including in the file requesting that the client contact the load distribution server a selectable element by which the client may directly contact the load distribution server through an initiative of a user of the client.

15. The system of claim 13, further comprising:

means for offering in the file requesting that the client contact the load distribution server a selectable element that can be selected to update a bookmark file to include the load distribution server.

16. The system of claim 15, wherein said system further comprises:

means for including, in the file requesting that the client contact the load distribution server, a selectable element for updating the bookmark file to exclude said content server.

17. The system of claim 13, wherein the means for determining whether said client'"'"'s request to receive said file from said content server originated as a reference from said content server further comprises means for determining, based on the recently of a time stamp contained within a client'"'"'s request to receive the file from said content server, whether said client'"'"'s request to receive said file from said content server originated as a reference from said content server.

18. The system of claim 13, further comprising:

means for allowing a user of the client sufficient time to read and react to the file requesting that the user of the client contact the load distribution server before contact with the load distribution server is established without intervention of the user.