Methods and apparatus for routing a content request

• US 7,315,541 B1
• Filed: 04/03/2002
• Issued: 01/01/2008
• Est. Priority Date: 04/03/2002
• Status: Active Grant

• Current Assignee: Cisco Technology, Inc. (Cisco Systems, Inc.)
• Original Assignee: Cisco Technology, Inc. (Cisco Systems, Inc.)
• Inventors: Housel, Barron, Tsang, Tzu-Ming
• Primary Examiner(s): Chan; Wing
• Assistant Examiner(s): Jones; Prenell
• Application Number:
  US10/115,555
• Time in Patent Office: 2,099 Days
• Field of Search: 370/392, 370389-401, 370/351, 370/498, 370/252, 370/238, 370/338, 370/469, 370/399, 370/352, 370/230, 370/235, 370/369, 370/258, 370/402, 370/236, 709/245, 709217-224, 709/230, 709/105, 709/206, 709227-229, 709/238, 709/244, 711/122, 711/124, 455/466, 455/412, 455/445, 455/427, 455/452, 379/220.01, 379/114.02, 379/221
• US Class Current: 370/392
• CPC Class Codes: H04L 45/306 Route determination based on the nature of the carried application
• CPC Class Codes: H04L 61/2557 Translation policies or rules
• CPC Class Codes: H04L 67/63 Routing a service request depending on the request content or context
• CPC Class Codes: H04W 40/02 Communication route or path selection, e.g. power-based or shortest path routing

Abstract

Mechanisms and techniques provide a method for routing a packet that includes a content request and an Internet Protocol address and port number that identify a source transmitting the packet. The method relates to selecting a routing policy to forward the packet, based upon at least a portion of content request. The method includes a data communications device receiving a packet having a content request and an Internet Protocol address and port number that identify a source transmitting the packet. The device performs a network address translation, based upon at least a portion of the content request, to translate the Internet Protocol address and port number of the packet to a respective communications device Internet Protocol address and communications device port number. The device then selects a routing policy based upon the communications device Internet Protocol address and routes the packet to a destination according to the routing policy.

Claims

1. In a data communications device, a method for routing a packet, the method comprising the steps of:

receiving a packet, the packet having a content request and an Internet Protocol address and port number that identify a source transmitting the packet;

performing a network address translation, based upon at least a portion of the content request, to translate the Internet Protocol address and port number of the packet to a respective communications device Internet Protocol address and communications device port number;

selecting a routing policy based upon the communications device Internet Protocol address; and

routing the packet to a destination based upon the routing policy;

wherein the step of selecting comprises the steps of;

converting the communications device Internet Protocol address of the packet into a resultant internet protocol address, and

selecting the routing policy for the content request based upon the resultant Internet Protocol address;

wherein the step of converting comprises combining the substitute Internet Protocol address from the packet with a masking function to generate a resultant Internet Protocol address.

2. The method of claim 1 wherein the step of performing further comprises the steps of:

assigning a policy identifier to the content request based upon at least a portion of the content request, the policy identifier relating to a respective routing policy;

associating the content request with a corresponding network address translation pool using the policy identifier, the corresponding network address translation pool having a plurality of communications device Internet Protocol addresses and a plurality of communications device port numbers and the network address translation pool being associated with the routing policy related to the policy identifier;

selecting a communications device Internet Protocol address number and a communications device port number from the network address translation pool; and

replacing the source Internet Protocol address of the packet with the communications device Internet Protocol address from the network address translation pool and replacing the source port number of the packet with the communications device port number from the network address translation pool.

3. The method of claim 1 wherein the step of selecting comprises:

comparing the resultant Internet Protocol address with Internet Protocol address entries in a lookup table, each Internet Protocol address entry corresponding to a routing policy; and

selecting a routing policy associated with the Internet Protocol address entry in the lookup table that matches the resultant Internet Protocol address.

4. The method of claim 1 further comprising identifying at least a portion of the content request.

5. The method of claim 1 further comprising parsing the content request into content request components.

6. The method of claim 1 further comprising connecting the data communications device to a routing policy database, the routing policy database providing routing policy information to the communications device.

7. The method of claim 1 further comprising determining if the content request is subject to routing with a routing policy.

8. The method of claim 1 wherein the step of receiving further comprises forwarding the packet to a processor portion of the data communications device, the processor portion having routing policy information.

9. The method of claim 1 further comprising forwarding the packet to a routing portion of the data communications device, the routing portion having routing policy information.

21. The method of claim 1, wherein:

routing the packet to the destination based upon the routing policy comprises routing the packet to the destination based upon the routing policy, the routing policy selected from the group consisting of a service for delivery of the packet, a security level for delivery of the packet, a type of transport for delivery of the packet, and a bandwidth for delivery of the packet.

10. A data communications device comprising:

at least one communications interface;

a controller; and

an interconnection mechanism coupling the at least one communications interface and the controller;

wherein the controller is configured to;

receive a packet, the packet comprising a content request and an Internet Protocol address and port number that identify a source transmitting the packet;

perform a network address translation, based upon at least a portion of the content request, to translate the Internet Protocol address and port number of the packet to a respective communications device Internet Protocol address and communications device port number;

select a routing policy based upon the communications device Internet Protocol address; and

route the packet to a destination based upon the routing policy;

wherein the controller, when selecting, is configured to;

convert the communications device Internet Protocol address of the packet into a resultant Internet Protocol address, and

select the routing policy for the content request based upon the resultant Internet Protocol address;

wherein the controller, when converting, is configured to combine the substitute Internet Protocol address from the packet with a masking function to generate a resultant Internet Protocol address.

11. The data communications device of claim 10 wherein the controller, when performing the network address translation, is configured to:

assign a policy identifier to the content request based upon at least a portion of the content request, the policy identifier relating to a respective routing policy;

associate the content request with a corresponding network address translation pool using the policy identifier, the corresponding network address translation pool having a plurality of communications device Internet Protocol addresses and a plurality of communications device port numbers and the network address translation pool being associated with the routing policy related to the policy identifier;

select a communications device Internet Protocol address number and a communications device port number from the network address translation pool; and

replace the source Internet Protocol address of the packet with the communications device Internet Protocol address from the network address translation pool and replacing the source port number of the packet with the communications device port number from the network address translation pool.

12. The data communications device of claim 10 wherein the controller, when selecting the routing policy, is configured to:

compare the resultant Internet Protocol address with Internet Protocol address entries in a lookup table, each Internet Protocol address entry corresponding to a routing policy; and

select a routing policy associated with the Internet Protocol address entry in the lookup table that matches the resultant Internet Protocol address.

13. The data communications device of claim 10 wherein the controller is further configured to perform the operation of identifying at least a portion of the content request.

14. The data communications device of claim 10 wherein the controller is further configured to perform the operation of parsing the content request into content request components.

15. The data communications device of claim 10 wherein the controller is further configured to perform the operation of connecting the data communications device to a routing policy database, the routing policy database providing routing policy information to the communications device.

16. The data communications device of claim 10 wherein the controller is further configured to perform the operation of determining if the content request is subject to routing with a routing policy.

17. The data communications device of claim 10 wherein the controller, when receiving a packet, is further configured to forward the packet to a processor portion of the data communications device, the processor portion having routing policy information.

18. The data communications device of claim 10 wherein the controller is further configured to perform the operation of forwarding the content request to a routing portion of the data communications device, the routing portion having routing policy information.

19. A computer program product having a computer-readable medium including computer program logic stored thereon that, when performed on a computer, causes the computer to:

receive a packet, the packet comprising a content request and an Internet Protocol address and port number that identify a source transmitting the packet;

perform a network address translation, based upon at least a portion of the content request, to translate the Internet Protocol address and port number of the packet to a respective communications device Internet Protocol address and communications device port number;

select a routing policy based upon the communications device Internet Protocol address;

route the packet to a destination based upon the routing policy;

when selecting;

convert the communications device Internet Protocol address of the packet into a resultant Internet Protocol address, and

select the routine policy for the content request based upon the resultant Internet Protocol address; and

when converting, combine the substitute Internet Protocol address from the packet with a masking function to generate a resultant Internet Protocol address.

20. A data communications device comprising:

at least one communications interface;

a controller; and

an interconnection mechanism coupling the at least one communications interface and controller;

wherein the controller includes;

means for receiving a packet, the packet comprising a content request and an Internet Protocol address and port number that identify a source transmitting the packet,

means for performing a network address translation, based upon at least a portion of the content request, to translate the Internet Protocol address and port number of the packet to a respective communications device Internet Protocol address and communications device port number,

means for selecting a routing policy based upon the communications device Internet Protocol address,

means for routing the packet to a destination based upon the routing policy,

wherein means for selecting comprises;

means for converting the communications device Internet Protocol address of the packet into a resultant Internet Protocol address, and

means for selecting the routing policy for the content request based upon the resultant Internet Protocol address; and

wherein means for converting comprises means for combining the substitute Internet Protocol address from the packet with a masking function to generate a resultant Internet Protocol address.

22. In a data communications device, a method for routing a packet, the method comprising the steps of:

receiving a packet, the packet having a content request and an Internet Protocol address and port number that identify a source transmitting the packet;

determining if the content request is subject to routing with a routing policy

performing a network address translation, based upon at least a portion of the content request, to translate the Internet Protocol address and port number of the packet to a respective communications device Internet Protocol address and communications device port number;

selecting the routing policy based upon the communications device Internet Protocol address; and

routing the packet to a destination based upon the routing policy.

23. A data communications device comprising:

at least one communications interface;

a controller; and

an interconnection mechanism coupling the at least one communications interface and the controller;

wherein the controller is configured to;

receive a packet, the packet comprising a content request and an Internet Protocol address and port number that identify a source transmitting the packet;

determine if the content request is subject to routing with a routing policy;

perform a network address translation, based upon at least a portion of the content request, to translate the Internet Protocol address and port number of the packet to a respective communications device Internet Protocol address and communications device port number;

select the routing policy based upon the communications device Internet Protocol address; and

route the packet to a destination based upon the routing policy.