Patent ID: 8635662

Claim:
A method for authenticating a user, comprising: determining, by computer, a trust level for the user after a first elapsed time, wherein the trust level is a function of the first elapsed time since the user previously provided authentication information, wherein the trust level decays as a function of the first elapsed time, and wherein a higher trust level is associated with a slower rate of decay of the trust level; receiving notice of an identified security threat that affects multiple users; determining a new rate of decay of the trust level based on the identified security threat; determining a new trust level after a second elapsed time since receiving notice of the identified security threat, wherein the new trust level is obtained by multiplying the second elapsed time with the new rate of decay of the trust level; calculating a transaction risk level based on a type of user transaction performed by the user; and requesting additional authentication information from the user when the transaction risk level exceeds the new trust level.