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Dr Sevasti Karatzouni PhD

Research Student

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Non-Intrusive Continuous User Authentication for Mobile Devices

The modern mobile device has become an everyday tool for users and business. Technological advancements in the device itself and the networks that connect them have enabled a range of services and data access which have introduced a subsequent increased security risk. Given the latter, the security requirements need to be re-evaluated and authentication is a key countermeasure in this regard. However, it has traditionally been poorly served and would benefit from research to better understand how authentication can be provided to establish sufficient trust. This thesis investigates the security requirements of mobile devices through literature as well as acquiring the user’s perspectives. Given the findings it proposes biometric authentication as a means to establish a more trustworthy approach to user authentication and considers the applicability and topology considerations. Given the different risk and requirements, an authentication framework that offers transparent and continuous is developed. A thorough end-user evaluation of the model demonstrates many positive aspects of transparent authentication. The technical evaluation however, does raise a number of operational challenges that are difficult to achieve in a practical deployment. The research continues to model and simulate the operation of the framework in an controlled environment seeking to identify and correlate the key attributes of the system. Based upon these results and a number of novel adaptations are proposed to overcome the operational challenges and improve upon the impostor detection rate. The new approach to the framework simplifies the approach significantly and improves upon the security of the system, whilst maintaining an acceptable level of usability.

Dr Sevasti Karatzouni

Director of studies: Dr Nathan Clarke
Other supervisors: Prof Steven Furnell, Dr Maria Papadaki

Journal papers

Beyond the PIN: Enhancing user authentication for mobile devices
Furnell SM, Clarke NL, Karatzouni S
Computer Fraud & Security, Volume 2008, Issue 8, pp12-17, 2008
More details | External link available

1 Journal papers

Conference papers

Towards a Flexible, Multi-Level Security Framework for Mobile Devices
Clarke NL, Karatzouni S, Furnell SM
Proceedings of the 10th Security Conference, Las Vegas, USA, 4-6 May, 2011
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Flexible and Transparent User Authentication for Mobile Devices
Clarke NL, Karatzouni S, Furnell SM
Proceedings of the 24th IFIP TC 11 International Information Security Conference, Pafos, Cyprus, May 18-20, ISBN: 978-3-642-01243-3, pp1-12, 2009
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Transparent Facial Recognition for Mobile Devices
Clarke NL, Karatzouni S, Furnell SM
Proceedings of the 7th Security Conference, Las Vegas, USA, 2nd-3rd June, 2008
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Device- versus Network-Centric Authentication Paradigms for Mobile Devices: Operational and Perceptual Trade-Offs
Karatzouni S, Clarke NL, Furnell SM
5th Australian Information Security Management Conference, Mount Lawley, Australia, 5th December, 2007
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Utilising Biometrics for Transparent Authentication on Mobile Devices
Karatzouni S, Clarke NL, Furnell SM
Proceedings of the 2nd International Conference on Internet Technologies and Applications, 4-7 September, Wrexham, UK, ISBN: 978-0-946881-54-3, pp549–557, 2007
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Keystroke Analysis for Thumb-based Keyboards on Mobile Devices
Karatzouni S, Clarke NL
Proceedings of the 22nd IFIP International Information Security Conference (IFIP SEC 2007), Sandton, South Africa, 14-16 May, pp. 253-263, 2007
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Perceptions of User Authentication on Mobile Devices
Karatzouni S, Furnell SM, Clarke NL, Botha RA
Proceedings of the ISOneWorld Conference, Las Vegas, USA, April 11-13, CD Proceedings (0-9772107-6-6), 2007
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7 Conference papers

Internal publications

Keystroke analysis as an authentication method for thumb-based keyboards on mobile handsets
Karatzouni S, Clarke NL
Advances in Network & Communication Engineering 4, ISBN: 978-1-84102-180-5, pp213-221, 2007
Can be ordered on-line.
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Device versus network-centric authentication models for mobile devices – operational and perceptual trade-offs
Karatzouni S, Clarke NL, Furnell SM
Proceedings of the Third Collaborative Research Symposium on Security, E-learning, Internet and Networking (SEIN 2007), Plymouth, UK, ISBN: 978-1-8410-2173-7, pp23-39, 2007
Can be ordered on-line.
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2 Internal publications

10 publication(s) - all categories.