A Survey of Keystroke Dynamics Biometrics <s> 1.1.3. <s> The use of stolen personal-identifying information, like Social Security numbers, to commit identity fraud continues to be a major problem. The fact that an impostor can pass as the genuine user by possession of stolen identification information is a weakness in current authentication systems. Adding a biometric layer to the traditional knowledge and token-based authentication systems is one way to counter this problem. Physical biometrics, such as fingerprint systems, are highly accurate; hence, they would be the first choice for such applications but are often inappropriate. Behavioral biometrics, like biometric typing patterns, have the potential to fill this gap as another level of security but this research identified some deficiencies in performance quality. Two research streams for improvements have emerged. The first approach attempts to improve performance by building better classifiers, while the second attempts to attain the same goal by using richer identifying inputs. Both streams assume that the typing biometric patterns are stable over time. This study investigates the validity of this assumption by analyzing how students’ typing patterns behave over time. The results demonstrate that typing patterns change over time due to learning resulting in several performance quality challenges. First, the changing patterns lead to deteriorating authentication accuracy. Second, the relevancy of the reference biometric template created during training becomes questionable. Third, the deterioration in accuracy compromises the security of the whole system and fourth, the net effect brings to question whether the biometric keypad is no longer “fit for use” as an authentication system. These are critical data quality issues that need to be addressed if behavioral biometrics are to play a significant role in minimizing authentication fraud. Possible solutions to the problem, including biometric template updating and choice of uncorrelated PIN combinations, are suggested as potential topics for future research. <s> BIB001 </s> A Survey of Keystroke Dynamics Biometrics <s> 1.1.3. <s> While online applications can provide convenience to individuals and organizations, they can pose significant remote user authentication challenges. One possible solution to these challenges is to utilize behavioral typing patterns to provide an additional layer of authentication. Such behavioral biometrics have the advantage of being revocable if compromised, unlike physical biometrics such as fingerprints. This study investigates the viability of biometric keypads. Results indicate that biometric keypads can differentiate authentic users from impostors even when a secure PIN has been compromised. Furthermore, it is shown that authentication accuracy can be improved through optimal PIN selection by avoiding correlated key combinations. <s> BIB002
Biometrics. Biometrics refers to certain physiological or behavioral characteristic that is uniquely associated to a person. This trait is highly distinctive and can be utilized for distinguishing different individuals. Physiological biometrics refers to a person's physical attribute, such as fingerprint, face, and iris. It is well known for its permanence and high uniqueness that promote high recognition accuracy. Unfortunately, it is not likely to be revoked if compromised (unable to change fingerprint pattern) BIB001 , may possibly suffer low public acceptance due to invasiveness (iris scanning), and could be unlikely practical in large-scale deployment due to implementation cost (DNA analysis). The way people do things such as speaking (voice), writing (signature), typing (keystroke dynamics), and walking style (gait recognition) are known as behavioral biometrics. Behavioral biometrics has the edge over its physiological counterpart on the ability to work in stealth mode verification. As such, minimal interaction is required during authentication process reduces invasiveness and thus promotes user acceptability. In addition, in the event if one's behavioral attribute is compromised, it is likely to be replaced (changing to a new password, thus, new keystroke print or new written signature) BIB002 . While these merits may be encouraging, they are normally inferior to physiological biometrics in terms of variability (voice changes along with aging factor) and may consequently influence verification accuracy.