Social network based PKI authentication

Patent metadata

Field	Value
Publication number	US-9369285-B2
Application number	US-201213419065-A
Country	US
Kind code	B2
Filing date	Mar 13, 2012
Priority date	Apr 28, 2011
Publication date	Jun 14, 2016
Grant date	Jun 14, 2016

Abstract

A user device generates a social graph-based user certificate that conveys a trust level to other users of the social network. A user certificate for a user is obtained, the user having a user public key and corresponding user private key. A plurality of potential signers is identified within one or more social networks. The certificate is then sent to the identified plurality of potential signers. One or more signed versions of the user certificate may be received from at least some of the plurality of potential signers. The user device may assign a signer weight to each signed version of the user certificate, each corresponding signer weight associated with the signer of each signed version of the certificate. The user certificate, the user signature, one or more signed versions of the user certificate, and the user-assigned signer weights are distributed to one or more recipients.

First claim

What is claimed is:

1. A method operational on a user device for generating a social graph based certificate, comprising:
obtaining a user certificate for a user of the user device, wherein the user is associated with a user public key and corresponding user private key;
identifying a plurality of potential signers within one or more social networks;
sending the user certificate from the user device to the plurality of potential signers;
receiving, at the user device, one or more signed versions of the user certificate from at least some of the plurality of potential signers;
assigning a signer weight for each of the one or more signed versions of the user certificate, each corresponding signer weight associated with the signer of each signed version of the user certificate; and
combining the user certificate, the one or more signed versions of the user certificate, the assigned signer weight for each of the one or more signed versions of the user certificate, and the identity of at least those signers of the one or more signed versions of the user certificate into a composite certificate.

2. The method of claim 1 , further comprising:
generating a user signature by signing at least part of the composite certificate using the user private key; and
appending the user signature to the composite certificate.

3. The method of claim 2 , wherein generating the user signature includes one of either:
signing the user certificate, including identities of the identified plurality of potential signers, using the user private key; or
signing the user certificate, including the received one or more signed versions of the user certificate, using the user private key.

4. The method of claim 3 , wherein the corresponding signer weights are also signed using the user private key to generate the user signature.

5. The method of claim 1 , wherein the plurality of potential signers is identified from contacts derived from emails or an address book for the user.

6. The method of claim 1 , further comprising:
sending identities of the identified plurality of potential signers, along with the user certificate, from the user device to the plurality of potential signers for signing by one or more of the potential signers.

7. The method of claim 1 , wherein the user certificate includes the user public key.

8. The method of claim 1 , wherein a first signed version of the user certificate, from among the one or more signed versions of the user certificate, is signed by a signer using a second private key and is authenticatable using a corresponding second public key.

9. The method of claim 1 , further comprising:
distributing the user certificate, a user signature, the one or more signed versions of the user certificate, and the one or more assigned signer weights to one or more recipients of the composite certificate.

10. The method of claim 1 , further comprising:
appending a user certificate timestamp or lifetime indicator to the user certificate at the user device prior to distribution to one or more recipients.

11. The method of claim 1 , further comprising:
adding the user-assigned signer weight for each signed version of the user certificate to the composite certificate.

12. The method of claim 11 , wherein the assigned signer weight for each signer is proportional to a trust relationship between the user and the signer.

13. The method of claim 11 , wherein the assigned signer weight for each signer is proportional to a relationship distance between the user and the signer within a social network.

14. The method of claim 11 , wherein the assigned weight for each signer is at least one of: a time-varying weight or a purpose-dependent weight.

15. The method of claim 11 , wherein the assigned weight for each signer is at least partially based on weights received from other users and which are authenticable by the user device.

16. The method of claim 11 , wherein for signers known to the user of the assigned signer weight is solely determined by the user, while for signers unknown to the user the assigned signer weight is at least partially based on weights provided by known signers for such unknown signers.

17. The method of claim 1 , further comprising:
obtaining a signer-specific weight for each signed version of the user certificate; and
adding the signer-specific weight for each signed version of the user certificate to the composite certificate.

18. The method of claim 17 , wherein each signer-specific weight is associated with a corresponding signer.

19. The method of claim 17 , wherein the signer-specific weight is generated by at least one of a community of users or a trusted third party.

20. A user device comprising:
a communication interface for communicating over a communication network;
a processing circuit coupled to the communication interface, the processing circuit configured to:
obtain a user certificate for a user of the user device, wherein the user is associated with a user public key and corresponding user private key;
identify a plurality of potential signers within one or more social networks;
send the user certificate from the user device to the plurality of potential signers;
receive, at the user device, one or more signed versions of the user certificate from at least some of the plurality of potential signers;
assign a signer weight for each of the one or more signed versions of the user certificate, each corresponding signer weight associated with the signer of each signed version of the user certificate; and
combine the user certificate, the one or more signed versions of the user certificate, the assigned signer weight for each of the one or more signed versions of the user certificate, and the identity of at least those signers of the one or more signed versions of the user certificate into a composite certificate.

21. The user device of claim 20 , wherein the processing circuit is further configured to:
generate a user signature by signing at least part of the composite certificate using the user private key; and
append the user signature to the composite certificate.

22. The user device of claim 21 , wherein to generate the user signature, the processing circuit is further configured to either:
sign the user certificate, including identities of the identified plurality of potential signers, using the user private key; or
sign the user certificate, including the received one or more signed versions of the user certificate, using the user private key.

23. The user device of claim 22 , wherein the corresponding signer weights are also signed using the user private key to generate the user signature.

24. The user device of claim 20 , wherein the processing circuit is further configured to:
send identities of the identified plurality of potential signers, along with the user certificate, from the user device to the plurality of potential signers for signing by one or more of the potential signers.

25. A user device comprising:
means for obtaining a user certificate for a user of the user device, wherein the user is associated with a user public key and corresponding user private key;
means for identifying a plurality of potential signers within one or more social networks;
means for sending the user certificate from the user device to the plurality of potential signers;
means for receiving, at the user device, one or more signed versions of the user certificate

Assignees

• Narayanan Vidya
• Rose Greg
• Dondeti Lakshminath Reddy
• Qualcomm Inc

Inventors

• Narayanan Vidya
• Rose Greg
• Dondeti Lakshminath Reddy

Classifications

• H04L29/06775

  Electricity · mapped topic

• H04L9/3247 Primary

  involving digital signatures · CPC title

• H04L9/006

  involving public key infrastructure [PKI] trust models (network architecture or network communication protocol for supporting authentication of entities using certificates in a packet data network H04L63/0823) · CPC title

• H04L63/0823

  using certificates (cryptographic mechanisms or cryptographic arrangements for entity authentication involving certificates H04L9/3263) · CPC title

• H04L9/30 Primary

  Public key, i.e. encryption algorithm being computationally infeasible to invert or user's encryption keys not requiring secrecy · CPC title