Anonymity server

• US 6,389,533 B1
• Filed: 02/05/1999
• Issued: 05/14/2002
• Est. Priority Date: 02/05/1999
• Status: Expired due to Term

• Current Assignee: Intel Corporation
• Original Assignee: Intel Corporation
• Inventors: Korta, Jean-Charles, Davis, Derek L.
• Primary Examiner(s): DeCady, Albert
• Assistant Examiner(s): KABAKOFF, STEPHEN ERIC
• Application Number:
  US09/244,803
• Time in Patent Office: 1,194 Days
• Field of Search: 713/190, 713/151, 713/152, 713/153, 713/154, 713/162, 713/200
• US Class Current: 713/162
• CPC Class Codes: H04L 63/0407 wherein the identity of one or more communicating identities is hidden cryptographic mechanisms or cryptographic arrangements for anonymous credentials or for identity based cryptographic systems H04L9/00

Abstract

An anonymity system including a cryptographic device. The cryptographic device of the anonymity system is adapted to initially determine whether a response to an incoming electronic message is requested. If so, an address of the anonymity system is encrypted with a key. In one embodiment, the key may be a public key of a system targeted to receive an outgoing electronic message from the anonymity system inclusive of data contained in the incoming electronic message. The encrypted address is placed into an outgoing electronic message before re-routing to the target system to allow the target system to re-route the response back to the anonymity system.

Claims

1. A cryptographic device comprising:

a memory to contain at least one key; and

a processor including circuitry to determine whether a response to an incoming electronic message is requested, to encrypt an address of a system associated with the cryptographic device with the key when the response is requested, and to place the encrypted address into an outgoing electronic message before transmission.

2. The cryptographic device of claim 1, wherein the memory is non-volatile.

3. The cryptographic device of claim 1, wherein the memory further comprises cryptographic software to decrypt at least one field of the incoming electronic message and to encrypt the address before being loaded into a field, the outgoing electronic message corresponding to the at least one field.

4. The cryptographic device of claim 1, wherein the memory further comprises software to counter traffic analysis by providing padding information to the outgoing electronic message.

5. The cryptographic device of claim 1, wherein the memory further comprises software to counter traffic analysis by providing an arbitrary delay before redirecting the outgoing electronic message.

6. The cryptographic device of claim 1, wherein the memory further comprises software to counter traffic analysis by partitioning the outgoing electronic message into multiple messages transmitted in succession.

7. The cryptographic device of claim 1 further comprising a random number generator operating in cooperation with the processor and the non-volatile memory.

8. The cryptographic device of claim 1, wherein the incoming electronic message includes a header and a body, the body including data targeted for an intended recipient.

9. The cryptographic device of claim 8, wherein the data of the incoming electronic message is encrypted with the public key of the intended recipient.

10. The cryptographic device of claim 8, wherein the body of the incoming electronic message further includes a message propagation field comprising:

a first field including information to identify an original sender of the incoming electronic message; and

a second field to contain an address of each intermediary system through which at least a portion of the incoming electronic message is routed.

11. The cryptographic device of claim 10, wherein the second field of the message propagation field is chronologically ordered with a most recent intermediary system placed in the most significant bytes of the second field.

12. The cryptographic device of claim 10 further comprising a third field including a signal value to identify what message the response pertains to.

13. The cryptographic device of claim 12 further comprising a fourth field to identify an intended recipient of the incoming electronic message.

14. An anonymity system comprising:

a system substrate; and

a daughter card coupled to the system substrate, the daughter card including a cryptographic device (i) to analyze an incoming electronic message to determine whether or not a response to the incoming electronic message is requested, (ii) to encrypt an address of the anonymity system with a key associated with a system to receive an outgoing electronic message from the cryptographic device, and (iii) to place the encrypted address into the outgoing electronic message before transmission.

15. The anonymity system of claim 14, wherein the system substrate comprising a host processor.

16. The anonymity system of claim 14, wherein the cryptographic device of the daughter card comprises a processor and a non-volatile memory to contain at least a public key and a private key associated with the anonymity system.

17. The anonymity system of claim 16, wherein the non-volatile memory of the cryptographic device further comprises software to produce the outgoing electronic message.

18. The anonymity system of claim 14, wherein the incoming electronic message includes a header and a body, the body of the incoming electronic message including a message propagation field.

19. The anonymity system of claim 18, wherein the message propagation field comprises

data to identify an original sender of the incoming electronic message; and

an address for each prior anonymity system through which the incoming electronic message has already been routed.

20. The anonymity system of claim 19, wherein the addresses being chronologically ordered within the message propagation field with an address of a most recent anonymity system is placed in a most significant bytes of the message propagation field.

21. The anonymity system of claim 18, wherein the body of the incoming electronic message further includes a target address field, a routing field and a control field.

22. The anonymity system of claim 21, wherein the target address field includes an address of a final, intended recipient of the incoming electronic message.

23. The anonymity system of claim 21, wherein the routing field includes control data to indicate when the outgoing electronic message is routed to a final, intended recipient.

24. The anonymity system of claim 21, wherein the control field includes an enable bit that, when set, indicates that the response is requested.

25. An article comprising a machine readable medium having instructions stored therein which, when executed, cause a computer to:

determine a state of at least one bit of an incoming electronic message, the at least one bit indicating whether a response message is permitted for the incoming electronic message;

encrypt an address of the anonymity system with a public key of a system targeted to receive an outgoing electronic message being based on the incoming electronic message; and

a routine to load the encrypted address into the outgoing electronic message before transmission.

26. The article of claim 25, wherein the incoming electronic message comprises a header and a body, the body of the incoming electronic message including a message propagation field.

27. The article of claim 26, wherein the message propagation field includes information to provide an encrypted return path for the response message.

28. The article of claim 25, wherein the body of the incoming electronic message further comprises a control field having the at least one bit that, when set, indicates that the response message is permitted.

29. The article of claim 25, wherein the body of the incoming electronic message comprises a target address field including an address of an intended recipient of the incoming electronic message.

30. An anonymity system comprising:

a circuit board; and

a cryptographic device coupled to the circuit board, the cryptographic device to decrypt at least one field of an incoming electronic message, to determine whether a response message to the incoming electronic message is requested by an original sender, and to place an address of the anonymity system having an encrypted format into an outgoing electronic message before transmission.