A user network station transmits a cookie including a user identifier and an augmenting factor transformed with one key of a first asymmetric crypto-key or with a symmetric crypto-key. A authenticating entity network station recovers the augmenting factor from the transformed augmenting factor with the other key of the first asymmetric crypto-key or with the symmetric crypto-key, and transmits a customized login page corresponding to the user identifier included in the received cookie. The user network station transmits a factor responsive to the transmitted customized login page. The authenticating entity network station generates a first key portion based on the transmitted factor, and validates the generated first key portion based on a second key portion of one key of a second asymmetric crypto-key associated with the user and on the other key of the second asymmetric crypto-key, and the recovered augmenting factor, to thereby authenticate the user.