Method and apparatus for the secure identification of the owner of a portable device

An authentication system is provided that includes a portable device and a decryption node. An individual uses the portable device, such as a portable device like a cell phone to compute a challenge and a response. The challenge and response is sent to a decryption node. In response, the decryption node computes a presumed response and compares the presumed response to the response of the portable device, in order to authenticate the individual associated with the portable device.