A new approach for keystroke-based authentication when using a cellular phone keypad as input device is presented. In the proposed method, users are authenticated using keystroke dynamics acquired when typing fixed alphabetic strings on a mobile phone keypad. The employed statistical classifier is able to perform user veri. cation with an average equal error rate of about 13%. The obtained experimental results suggest that, when using mobile devices, a strong secure authentication scheme cannot rely on the sole keystroke dynamics, which however can be a module of a more complex system including, as basic security, a password-based protocol eventually hardened by keystroke analysis.
Campisi, P., Maiorana, E., Neri, A. (2009). User Authentication using keystroke dynamics for cellular phones. IET SIGNAL PROCESSING, 3(4), 333-341 [10.1049/iet-spr.2008.0171].