Outline Behavioural Biometrics Signature Recognition Keystroke Dynamics Gesture Recognition Continuous Authentication Biometrics - IT00207/IT28X07 Lecture 7: Behavioural Biometrics Prof. DT van der Haar Academy of Computer Science and Software Engineering University of Johannesburg Biometrics - IT00207/IT28X07 1/41 Academy of Computer Science and Software Engineering Outline Behavioural Biometrics Signature Recognition 1 Behavioural Biometrics Types of Behavioural Biometrics 2 Signature Recognition History What is a Signature Applications Properties Features Limitations Algorithms 3 Keystroke Dynamics Properties Applications Additional Uses Capture and Features Algorithms Biometrics - IT00207/IT28X07 2/41 Keystroke Dynamics Gesture Recognition Continuous Authentication Academy of Computer Science and Software Engineering Outline Behavioural Biometrics Signature Recognition Keystroke Dynamics 4 Gesture Recognition Applications Properties Capture Features Limitations Algorithms 5 Continuous Authentication Traditional Authentication Properties of Continuous Authentication Considerations Future of Continuous Authentication Biometrics - IT00207/IT28X07 3/41 Gesture Recognition Continuous Authentication Academy of Computer Science and Software Engineering Outline Behavioural Biometrics Signature Recognition Keystroke Dynamics Gesture Recognition Continuous Authentication Types of Behavioural Biometrics Aside from genetic, phenotypic and psychological biometrics attributes, there are behavioural attributes that can be also used as biometrics: Signature Recognition Keystroke Dynamics Gesture Recognition Gait Recognition Voice? Other more esoteric attributes? Biometrics - IT00207/IT28X07 4/41 Academy of Computer Science and Software Engineering Outline Behavioural Biometrics Signature Recognition Keystroke Dynamics Gesture Recognition Continuous Authentication Signature Recognition Biometrics - IT00207/IT28X07 5/41 Academy of Computer Science and Software Engineering Outline Behavioural Biometrics Signature Recognition Keystroke Dynamics Gesture Recognition Continuous Authentication History Kings issuing commands Artists POS confirmation Overall has four decades of research! Biometrics - IT00207/IT28X07 6/41 Academy of Computer Science and Software Engineering Outline Behavioural Biometrics Signature Recognition Keystroke Dynamics Gesture Recognition Continuous Authentication What is a signature? A handwritten depiction of one’s name that is indicative of: providence (identity) or their will. Biometrics - IT00207/IT28X07 7/41 Academy of Computer Science and Software Engineering Outline Behavioural Biometrics Signature Recognition Keystroke Dynamics Gesture Recognition Continuous Authentication Figure: Examples of Signatures Biometrics - IT00207/IT28X07 8/41 Academy of Computer Science and Software Engineering Outline Behavioural Biometrics Signature Recognition Keystroke Dynamics Gesture Recognition Continuous Authentication Applications Biometrics applications can be already used in place of the traditional signature. POS applications Credit card applications Data access Computer Sign on Biometrics - IT00207/IT28X07 9/41 Academy of Computer Science and Software Engineering Outline Behavioural Biometrics Signature Recognition Keystroke Dynamics Gesture Recognition Continuous Authentication Capture A signature can either be captured: Offline with a scanner or online with a digitising tablet and stylus or special pen Biometrics - IT00207/IT28X07 10/41 Academy of Computer Science and Software Engineering Outline Behavioural Biometrics Signature Recognition Keystroke Dynamics Gesture Recognition Continuous Authentication Types of Approaches Signature Recognition can either verify the: Static product Dynamic product Biometrics - IT00207/IT28X07 11/41 Academy of Computer Science and Software Engineering Outline Behavioural Biometrics Signature Recognition Keystroke Dynamics Gesture Recognition Continuous Authentication Static Product The features for the static product include: Geometry Curvature Shape Biometrics - IT00207/IT28X07 12/41 Academy of Computer Science and Software Engineering Outline Behavioural Biometrics Signature Recognition Keystroke Dynamics Gesture Recognition Continuous Authentication Figure: A signature showing shape and curvature. Biometrics - IT00207/IT28X07 13/41 Academy of Computer Science and Software Engineering Outline Behavioural Biometrics Signature Recognition Keystroke Dynamics Gesture Recognition Continuous Authentication Dynamic Product The features for the dynamic product include: Spatial coordinate x (t) Spatial coordinate y (t) Pressure p(t) Azimuth az(t) Inclination in(t) Biometrics - IT00207/IT28X07 14/41 Academy of Computer Science and Software Engineering Outline Behavioural Biometrics Signature Recognition Keystroke Dynamics Gesture Recognition Continuous Authentication Limitations Mostly for authentication not identification Requires considerable devotion from same person Affected by the following environmental factors: Type of pen Weight of pen Pen diameter Friction of surface Importance of document Biometrics - IT00207/IT28X07 15/41 Academy of Computer Science and Software Engineering Outline Behavioural Biometrics Signature Recognition Keystroke Dynamics Gesture Recognition Continuous Authentication Algorithms Preprocessing and feature extraction depends on capture. However, classification/matching occurs using: Dynamic Time Warping (DTW) Hidden Markov models (HMM) Vector Quantization (VQ) Biometrics - IT00207/IT28X07 16/41 Academy of Computer Science and Software Engineering Outline Behavioural Biometrics Signature Recognition Keystroke Dynamics Gesture Recognition Continuous Authentication Keystroke Dynamics Biometrics - IT00207/IT28X07 17/41 Academy of Computer Science and Software Engineering Outline Behavioural Biometrics Signature Recognition Keystroke Dynamics Gesture Recognition Continuous Authentication History Typewriters Stock Market Teleprinter (1870s) Computer Terminals Soft Keyboards for Smart Devices Biometrics - IT00207/IT28X07 18/41 Academy of Computer Science and Software Engineering Outline Behavioural Biometrics Signature Recognition Keystroke Dynamics Gesture Recognition Continuous Authentication Types of Keyboards Standards Laptop-Sized Flexible Keyboards Handheld Thumb-sized Other (chorded, projection and optical) Biometrics - IT00207/IT28X07 19/41 Academy of Computer Science and Software Engineering Outline Behavioural Biometrics Signature Recognition Keystroke Dynamics Gesture Recognition Continuous Authentication Applications Does not require special hardware Can be used for continued monitoring (Spyware) Used to harden passwords (with rules) Examples include BioPassword, Psylock, bioChec and iMagic Biometrics - IT00207/IT28X07 20/41 Academy of Computer Science and Software Engineering Outline Behavioural Biometrics Signature Recognition Keystroke Dynamics Gesture Recognition Continuous Authentication Additional Uses Man versus machine Anomaly detection Brute force attempt detection Biometrics - IT00207/IT28X07 21/41 Academy of Computer Science and Software Engineering Outline Behavioural Biometrics Signature Recognition Keystroke Dynamics Gesture Recognition Continuous Authentication Capture and Features Capture just requires normal typing and features include a digraph representation that can contain: Timing traces Time delay between pressing the first and second key Key and down events (dwell time) However, there is no agreed upon standard and there is still room for improvement. Biometrics - IT00207/IT28X07 22/41 Academy of Computer Science and Software Engineering Outline Behavioural Biometrics Signature Recognition Keystroke Dynamics Gesture Recognition Continuous Authentication Algorithms Features: Euclidean distance Manhattan distance Mahalanobis distance Classification: K-Nearest neighbour Probabilistic Neural Networks (PNN) Biometrics - IT00207/IT28X07 23/41 Academy of Computer Science and Software Engineering Outline Behavioural Biometrics Signature Recognition Keystroke Dynamics Gesture Recognition Continuous Authentication Gesture Recognition Biometrics - IT00207/IT28X07 24/41 Academy of Computer Science and Software Engineering Outline Behavioural Biometrics Signature Recognition Keystroke Dynamics Gesture Recognition Continuous Authentication History Structured gestures Sign language Monitoring Biometrics - IT00207/IT28X07 25/41 Academy of Computer Science and Software Engineering Outline Behavioural Biometrics Signature Recognition Keystroke Dynamics Gesture Recognition Continuous Authentication Applications Relatively esoteric but widespread use in the following areas are making it more prevalent: Gaming Television and Appliance manufacturers Mobile Computing Surveillance Wearable Computing Biometrics - IT00207/IT28X07 26/41 Academy of Computer Science and Software Engineering Outline Behavioural Biometrics Signature Recognition Keystroke Dynamics Gesture Recognition Continuous Authentication Properties Human physical locomotion can be captured on various levels: Macro scale (Body and limbs, especially for gait!) Micro scale (Hand, finger and facial expressions) Biometrics - IT00207/IT28X07 27/41 Academy of Computer Science and Software Engineering Outline Behavioural Biometrics Signature Recognition Keystroke Dynamics Gesture Recognition Continuous Authentication Categories of Gestures There are two categories of gestures: Offline gestures (gesture to activate a menu) Online gestures (rotate tangible object) Biometrics - IT00207/IT28X07 28/41 Academy of Computer Science and Software Engineering Outline Behavioural Biometrics Signature Recognition Keystroke Dynamics Gesture Recognition Continuous Authentication Types of Gestures In interactive gesture systems there are the following types of gestures: Semiotic Ergotic Epistemic Symbolic Deictic Iconic Pantomimic For an explanation consult Castro, Arjunan &Kumar, 2015 Biometrics - IT00207/IT28X07 29/41 Academy of Computer Science and Software Engineering Outline Behavioural Biometrics Signature Recognition Keystroke Dynamics Gesture Recognition Continuous Authentication Capture Uses sensors such as: Touch screen Accelerometer Camera Biometrics - IT00207/IT28X07 30/41 Academy of Computer Science and Software Engineering Outline Behavioural Biometrics Signature Recognition Keystroke Dynamics Gesture Recognition Continuous Authentication Features In order to derive: Velocity Direction Timings (using velocity maps) Pathing Biometrics - IT00207/IT28X07 31/41 Academy of Computer Science and Software Engineering Outline Behavioural Biometrics Signature Recognition Keystroke Dynamics Gesture Recognition Continuous Authentication Limitations Susceptible to sensor-based limitations (such as sensitivity and calibration) Speed of gestures limited by hardware Requires physical space Requires user acceptance Biometrics - IT00207/IT28X07 32/41 Academy of Computer Science and Software Engineering Outline Behavioural Biometrics Signature Recognition Keystroke Dynamics Gesture Recognition Continuous Authentication Figure: Gesture Recognition Algorithm Hierarchy Biometrics - IT00207/IT28X07 33/41 Academy of Computer Science and Software Engineering Outline Behavioural Biometrics Signature Recognition Keystroke Dynamics Gesture Recognition Continuous Authentication Algorithms Preprocessing (Target or ROI selection) Target representation (Blob tracking, Contour tracking, Feature matching, etc.) Filtering and data association (Kalman and Particle filters) Very similar to face detection, however, the path of the detected object is also important! Biometrics - IT00207/IT28X07 34/41 Academy of Computer Science and Software Engineering Outline Behavioural Biometrics Signature Recognition Keystroke Dynamics Gesture Recognition Continuous Authentication Videos https://www.youtube.com/watch?v=Jd3-eiid-Uw&t=2m29s https://www.youtube.com/watch?v=4uY-MyoRq4c Biometrics - IT00207/IT28X07 35/41 Academy of Computer Science and Software Engineering Outline Behavioural Biometrics Signature Recognition Keystroke Dynamics Gesture Recognition Continuous Authentication Continuous Authentication Biometrics - IT00207/IT28X07 36/41 Academy of Computer Science and Software Engineering Outline Behavioural Biometrics Signature Recognition Keystroke Dynamics Gesture Recognition Continuous Authentication Traditional Authentication Requires one authentication event only when it is needed However, between events subversion can occur More than once? Biometrics - IT00207/IT28X07 37/41 Academy of Computer Science and Software Engineering Outline Behavioural Biometrics Signature Recognition Keystroke Dynamics Gesture Recognition Continuous Authentication Properties of Traditional Authentication Typically one location Strict authentication protocol Ideal configuration parameters Bottlenecks can form Biometrics - IT00207/IT28X07 38/41 Academy of Computer Science and Software Engineering Outline Behavioural Biometrics Signature Recognition Keystroke Dynamics Gesture Recognition Continuous Authentication Continuous Authentication More than on authentication How often? Trust? Are all events created equal? How do we deal with denial? Biometrics - IT00207/IT28X07 39/41 Academy of Computer Science and Software Engineering Outline Behavioural Biometrics Signature Recognition Keystroke Dynamics Gesture Recognition Continuous Authentication Considerations The considerations when choosing continuous authentication include: Resources Availability Noise Usability versus Security Biometrics - IT00207/IT28X07 40/41 Academy of Computer Science and Software Engineering Outline Behavioural Biometrics Signature Recognition Keystroke Dynamics Gesture Recognition Continuous Authentication Future of Continuous Authentication Mobile Computing Wearable Computing Computational resources Biometrics - IT00207/IT28X07 41/41 Academy of Computer Science and Software Engineering
