  Authentication based on keystroke dynamics is a convenient biometric
approach, easy in use, transparent, and cheap as it does not require a
dedicated sensor. Keystroke authentication, as part of multi factor
authentication, can be used in remote display access to guarantee the security
of use of remote connectivity systems during the access control phase or
throughout the session. This paper investigates how network conditions and
additional host interaction may impact the behavioural pattern of keystrokes
when used in a remote desktop application scenario. We focus on the timing of
adjacent keys and investigate this impact by calculating the variations of the
Euclidean distance between a reference profile and resulting profiles following
such impairments. The experimental results indicate that variations of
congestion latency, whether produced by adjacent traffic sources or by
additional remote desktop interactions, have a substantive impact on the
Euclidian distance, which in turn may affect the effectiveness of the biometric
authentication algorithm. Results also indicate that data flows within remote
desktop protocol are not prioritized and therefore additional traffic will have
a significant impact on the keystroke timings, which renders continuous
authentication less effective for remote access and more appropriate for
one-time login.

Cryptography and Security