Apparatus and methods for providing translucent proxies in a communications network

• US 7,386,631 B1
• Filed: 08/26/2005
• Issued: 06/10/2008
• Est. Priority Date: 11/19/1999
• Status: Expired due to Fees

• Current Assignee: AT&T Corporation (AT&T, Inc.)
• Original Assignee: AT&T Corporation (AT&T, Inc.)
• Inventors: Spatscheck, Oliver, Sibal, Sandeep, Rodriguez, Pablo
• Primary Examiner(s): Nguyen; Quang N.
• Application Number:
  US11/213,061
• Time in Patent Office: 1,019 Days
• Field of Search: 709/202, 709/203, 709/219, 709/243, 709/245
• US Class Current: 709/238
• CPC Class Codes: H04L 67/2871 Implementation details of single intermediate entities
• CPC Class Codes: H04L 67/56 Provisioning of proxy services store-and-forward switching systems in data switching networks H04L12/54
• CPC Class Codes: H04L 69/16 Implementation or adaptation of Internet protocol [IP], of transmission control protocol [TCP] or of user datagram protocol [UDP]
• CPC Class Codes: H04L 69/163 In-band adaptation of TCP data exchange; In-band control procedures

Abstract

The Translucent Proxying of TCP (TPOT) device and methods use TCP-OPTIONS and IP tunneling to guarantee that all IP packets belonging to a specific TCP connection will traverse the proxy which intercepts the first packet of data. This guarantee allows the ad-hoc deployment of TPOT devices anywhere within the communication network, and does not restrict the placement of proxy devices at the edge of the network. Furthermore, no extra signaling support is required for the TPOT device to properly function while the addition of TPOT devices to communication networks significantly improves the throughput of intercepted TCP packets of data.

Claims

1. A method for transmitting data over a network from a source to a destination through a plurality of intermediary devices, wherein said plurality of intermediary devices comprises at least one proxying device and at least one non-proxying device, the method comprising:

receiving a request for data, said request having an identifier, wherein the identifier designates the request as a proxy-enabled request;

recognizing the identifier in the request by said at least one proxying device;

intercepting the request after recognizing the identifier and subsequently intercepting all of the remaining associated data packets so that requested data associated with the request will be forwarded by said at least one proxying device; and

transmitting the requested data from the source to the destination through by said at least one proxying device.

2. The method in claim 1, wherein the request is configured into an initial message by a host, the message containing an option field enclosing the identifier that allows the requested data to be forwarded by said at least one proxying device.

3. The method in claim 1, wherein said at least one proxying device is a proxy, the proxy receiving from the source an initial message of the request that has the identifier in an option field, the proxy recognizing the identifier and responding to the source by sending an acknowledgment message to the source.

4. The method in claim 3, wherein the proxy is located anywhere within the network.

5. The method in claim 4, wherein the proxy encodes an address of the proxy in the option field within the acknowledgment message.

6. The method in claim 1, wherein said at least one proxying device is a router, the router forwarding the requested data toward the destination over the network without recognizing the identifier in an option field of a message.

7. The method in claim 5, wherein the proxy simultaneously forwards the initial message to the destination while the proxy is sending an acknowledgment message to the source, thereby establishing two simultaneous connections.

8. The method in claim 7, wherein after the source receives the acknowledgment message, the source transmits at least one additional message to the destination that corresponds to the requested data.

9. The method in claim 8, wherein each of the at least one additional message is configured by encapsulating a first packet of data within a second packet of data, prefixing a header of the first packet with an address of the proxy and the second packet with an address of the destination.

10. The method in claim 9, wherein the header of the first packet is stripped off after the message is received by the proxy, while the second packet is forwarded to the destination.

11. The method in claim 10, wherein the destination responds to the proxy after receiving the second packet by sending an acknowledgment message to the proxy.

12. The method in claim 11, wherein after the two simultaneous connections are established, the source responds to the acknowledgment message by transmitting at least one additional message to the destination that corresponds to the requested data and the destination responds to the initial message by transmitting an acknowledgment message to the proxy.

13. The method in claim 12, wherein the proxy responds to the acknowledgment message by transmitting at least one additional message to the destination that corresponds to the requested data.

14. The method in claim 13, wherein a plurality of proxies are located anywhere within a network and are used to forward the requested data to the destination.

15. A device that transmits data over a network from a source to a destination through a plurality of intermediary devices, wherein said plurality of intermediary devices comprises at least one proxying device and at least one non-proxying device, comprising:

a receiving part that receives a request for data, which includes an identifier that designates the request as a proxy-enabled request;

a recognition part in said at least one proxying device that recognizes the identifier in the request;

an intercepting part that intercepts the request after the recognition and subsequently intercepting all of the remaining associated data packets so that requested data associated with said request will be forwarded by said at least one proxying device; and

a transmitting part that transmits the requested data to the destination through said at least one proxying device.

16. The device in claim 15, wherein the request is configured into an initial message by a host, the message containing an option field enclosing the identifier that allows the requested data to be forwarded by said at least one proxying device.

17. The device in claim 15, wherein said at least one proxying device is a proxy, the proxy receiving from the source an initial message of the request that has the identifier in an option field, the proxy recognizing the identifier and responding to the source by sending an acknowledgment message to the source.

18. The device in claim 17, wherein the proxy is located anywhere within the network.

19. The device in claim 18, wherein the proxy encodes an address of the proxy in the option field within the acknowledgment message.

20. The device in claim 15, wherein said at least one proxying device is a router, the router forwarding the requested data toward the destination over the network without recognizing the identifier in an option field of a message.

21. The device in claim 19, wherein the proxy simultaneously forwards the initial message to the destination while the proxy is sending an acknowledgment message to the source, thereby establishing two simultaneous connections.

22. The device in claim 21, wherein after the source receives the acknowledgment message, the source transmits at least one additional message to the destination that corresponds to the requested data.

23. The device in claim 22, wherein each of the at least one additional message is configured by encapsulating a first packet of data within a second packet of data, prefixing a header of the first packet with an address of the proxy and the second packet with an address of the destination.

24. The device in claim 23, wherein the header of the first packet is stripped off after the message is received by the proxy, while the second packet is forwarded to the destination.

25. The device in claim 24, wherein the destination responds to the proxy after receiving the second packet by sending an acknowledgment message to the proxy.

26. The device in claim 25, wherein after the two simultaneous connections are established, the source responds to the acknowledgment message by transmitting at least one additional message to the destination that corresponds to the requested data and the destination responds to the initial message by transmitting an acknowledgment message to the proxy.

27. The device in claim 26, wherein the proxy responds to the acknowledgment message by transmitting at least one additional message to the destination that corresponds to the requested data.

28. The device in claim 27, wherein a plurality of proxies are located anywhere within a network and are used to forward the requested data to the destination.