Risk Estimation for a Secure & Usable User Authentication Mechanism for Mobile Passenger ID Devices

User Authentication in mobile devices acts as a
first line of defense verifying the user´s identity to allow
access to the resources of a device and typically was based on
‘‘something the user knows’’, known also as knowledge-based
user authentication for several decades. However, recent
studies point out that although knowledge-based user
authentication has been the most popular for authenticating
an individual, nowadays it is no more considered secure and
convenient for the mobile user as it is imposing several
limitations in terms of security and usability. These
limitations stress the need for the development and
implementation of more secure and usable user
authentication methods. Toward this direction, user
authentication based on the ‘‘something the user is’’ has
caught the attention. This category includes authentication
methods which make use of human physical characteristics
(also referred to as physiological biometrics), or involuntary
actions (also referred to as behavioral biometrics). In
particular, risk-based user authentication based on
behavioral biometrics appears to have the potential to
increase the reliability of authentication without sacrificing
usability.