Patent ID: 8613057

Claim:
A method comprising: receiving, by a first computer system, a request from a user at a second computer system to access data managed by the first computer system, where authentication is required for the user at the second computer system to access the data; receiving, by the first computer system from the second computer system, an information packet provided for the authentication, the information packet comprising a user assertion that is an article of information that declares an existence of personal user data unknown to the first computer system without revealing the personal user data to the first computer system and is generated by a third computer system for the second computer system based on information provided by the user; transmitting, by the first computer system in response to the request, an encrypted challenge to the second computer system, wherein the encrypted challenge is encrypted with a public key that is an asymmetric counterpart to a private key stored by the second computer system; receiving, from the second computer system in response to the encrypted challenge, an encrypted response that is encrypted with the private key; verifying, by the first computer system, that the encrypted response received from the second computer system is valid; verifying, by the first computer system, that the user assertion received in the information packet from the second computer system is true; creating, by the first computer system, a confirmation of the authentication proving that the user assertion is valid, wherein the authentication does not comprise the personal user data; and sending, by the first computer system, the confirmation of the authentication of the user assertion to the second computer system in response to the request to allow the user to access the data.