Wireless Key Identification Systems-Two Factor Authentication Systems (Deal 254)

This invention is generally related to user authentication. Techniques are disclosed for authentication by storing a user PIN and an asymmetric key pair of authorized users along with primary user identification. Also disclosed receiving primary identification and a PIN from a user, authenticate primary identification, generate a passcode, encrypt using stored key and communicate encrypted passcode to the user. The technology may be implemented in security systems, authentication systems, facility entry systems, etc.