Usable Authentication in Virtual Reality: Exploring the Usability of PINs and Gestures

Virtual Reality (VR) is becoming increasingly popular with its ability to offer new forms of interaction, user interface, and immersion not only for recreation but also for work, therapy, arts, or education. These new spaces need to be safeguarded by authentication similar to conventional IT systems. However, porting conventional interfaces to VR has often been found to be less than optimal as it fails to fully embrace the technology's potential and potentially disrupt the immersive experience. This paper evaluates and compares the usability of two major authentication methods for VR: 2D Personal Identification Number (PIN) and gesture-based authentication - with 40 participants. While prior research has shown promising results in authentication security, there is a lack of studies specifically on usability in VR. Our findings indicate that the type of authentication and the user's experience level affect usability, with gesture-based authentication having a higher usability score than a PIN and having faster authentication times. Hereby, users with less VR experience profited the most from a natural interaction mode for VR. The results suggest that developers should rather choose a native interaction mode in VR than try to port a familiar conventional interaction such as number pads for PINs.