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- Creators: Barrett, The Honors College
- Creators: Mieth, Justin Richard
- Creators: Ossanna, Meilin Ryan
- Status: Published
Description
Keyboard input biometric authentication systems are software systems which record keystroke information and use it to identify a typist. The primary statistics used to determine the accuracy of a keyboard biometric authentication system are the false acceptance rate (FAR) and false rejection rate (FRR), which are aimed to be as low as possible [1]. However, even if a system has a low FAR and FRR, there is nothing stopping an attacker from also monitoring an individual's typing habits in the same way a legitimate authentication system would, and using its knowledge of their habits to recreate virtual keyboard events for typing arbitrary text, with precise timing mimicking those habits, which would theoretically spoof a legitimate keyboard biometric authentication system into thinking it is the intended user doing the typing. A proof of concept of this very attack, called keyboard input biometric authentication spoofing, is the focus of this paper, with the purpose being to show that even if a biometric authentication system is reasonably accurate, with a low FAR and FRR, it can still potentially be very vulnerable to a well-crafted spoofing system. A rudimentary keyboard input biometric authentication system was written in C and C++ which drew influence from already existing methods and attempted new methods of authentication as well. A spoofing system was then built which exploited the authentication system's statistical representation of a user's typing habits to recreate keyboard events as described above. This proof of concept is aimed at raising doubts about the idea of relying too heavily upon keyboard input based biometric authentication systems since the user's typing input can demonstrably be spoofed in this way if an attacker has full access to the system, even if the system itself is accurate. The results are that the authentication system built for this study, when ran on a database of typing event logs recorded from 15 users in 4 sessions, had a 0% FAR and FRR (more detailed analysis of FAR and FRR is also presented), yet it was still very susceptible to being spoofed, with a 44% to 71% spoofing rate in some instances.
ContributorsJohnson, Peter Thomas (Author) / Nelson, Brian (Thesis director) / Amresh, Ashish (Committee member) / Computer Science and Engineering Program (Contributor) / Barrett, The Honors College (Contributor)
Created2016-05
Description
Most daily living tasks consist of pairing a series of sequential movements, e.g., reaching to a cup, grabbing the cup, lifting and returning the cup to your mouth. The process by which we control and mediate the smooth progression of these tasks is not well understood. One method which we can use to further evaluate these motions is known as Startle Evoked Movements (SEM). SEM is an established technique to probe the motor learning and planning processes by detecting muscle activation of the sternocleidomastoid muscles of the neck prior to 120ms after a startling stimulus is presented. If activation of these muscles was detected following a stimulus in the 120ms window, the movement is classified as Startle+ whereas if no sternocleidomastoid activation is detected after a stimulus in the allotted time the movement is considered Startle-. For a movement to be considered SEM, the activation of movements for Startle+ trials must be faster than the activation of Startle- trials. The objective of this study was to evaluate the effect that expertise has on sequential movements as well as determining if startle can distinguish when the consolidation of actions, known as chunking, has occurred. We hypothesized that SEM could distinguish words that were solidified or chunked. Specifically, SEM would be present when expert typists were asked to type a common word but not during uncommon letter combinations. The results from this study indicated that the only word that was susceptible to SEM, where Startle+ trials were initiated faster than Startle-, was an uncommon task "HET" while the common words "AND" and "THE" were not. Additionally, the evaluation of the differences between each keystroke for common and uncommon words showed that Startle was unable to distinguish differences in motor chunking between Startle+ and Startle- trials. Explanations into why these results were observed could be related to hand dominance in expert typists. No proper research has been conducted to evaluate the susceptibility of the non-dominant hand's fingers to SEM, and the results of future studies into this as well as the results from this study can impact our understanding of sequential movements.
ContributorsMieth, Justin Richard (Author) / Honeycutt, Claire (Thesis director) / Santello, Marco (Committee member) / Harrington Bioengineering Program (Contributor) / Barrett, The Honors College (Contributor)
Created2018-05
Description
Previous research has shown that a loud acoustic stimulus can trigger an individual's prepared movement plan. This movement response is referred to as a startle-evoked movement (SEM). SEM has been observed in the stroke survivor population where results have shown that SEM enhances single joint movements that are usually performed with difficulty. While the presence of SEM in the stroke survivor population advances scientific understanding of movement capabilities following a stroke, published studies using the SEM phenomenon only examined one joint. The ability of SEM to generate multi-jointed movements is understudied and consequently limits SEM as a potential therapy tool. In order to apply SEM as a therapy tool however, the biomechanics of the arm in multi-jointed movement planning and execution must be better understood. Thus, the objective of our study was to evaluate if SEM could elicit multi-joint reaching movements that were accurate in an unrestrained, two-dimensional workspace. Data was collected from ten subjects with no previous neck, arm, or brain injury. Each subject performed a reaching task to five Targets that were equally spaced in a semi-circle to create a two-dimensional workspace. The subject reached to each Target following a sequence of two non-startling acoustic stimuli cues: "Get Ready" and "Go". A loud acoustic stimuli was randomly substituted for the "Go" cue. We hypothesized that SEM is accessible and accurate for unrestricted multi-jointed reaching tasks in a functional workspace and is therefore independent of movement direction. Our results found that SEM is possible in all five Target directions. The probability of evoking SEM and the movement kinematics (i.e. total movement time, linear deviation, average velocity) to each Target are not statistically different. Thus, we conclude that SEM is possible in a functional workspace and is not dependent on where arm stability is maximized. Moreover, coordinated preparation and storage of a multi-jointed movement is indeed possible.
ContributorsOssanna, Meilin Ryan (Author) / Honeycutt, Claire (Thesis director) / Schaefer, Sydney (Committee member) / Harrington Bioengineering Program (Contributor) / Barrett, The Honors College (Contributor)
Created2016-12