Patent ID: 8094812

Claim:
A system comprising: an authentication server device to: receive a first form of a password from a client device according to an authentication protocol, and authenticate the client device based on a comparison of the first form of the password to a value, derived from a second form of the password and stored in a password database, where the authentication server fails to authenticate the client device when the first form of the password is different than the value derived from the second form of the password; and a server device to: establish, when, based on the comparison, the authentication server device fails to authenticate the client device, a secure connection between a quarantine network and the client device, receive a plain-text password from the client device over the secure connection, authenticate the client device based on comparing a value derived from the plain-text password with the value derived from the second form of the password, update, when the client device is authenticated, the password database with a third form of the password that enables the authentication server device to successfully authenticate the client device based on the first form of the password, receive, after updating the password database with the third form of the password, a subsequent first form of the password, from the client device, retrieve the third form of the password from the password database derive a second value from the third form of the password, compare the subsequent first form of the password to the second value, and authenticate the client device based on comparing the subsequent first form of the password to the second value.