Usability Assessment of the OnlyKey Hardware Two-Factor Authentication Key Among Low Vision or Blind Users

TL;DR

This study evaluates the usability of the OnlyKey hardware two-factor authentication device for low vision or blind users, revealing significant setup and usability challenges that hinder adoption among this group.

Contribution

It provides the first empirical usability assessment of OnlyKey for visually impaired users, highlighting specific design issues affecting this population.

Findings

Over half of participants could not complete setup

Lack of tactile cues caused usability difficulties

Hardware key was often abandoned due to usability issues

Abstract

Hardware security keys undoubtedly have advantage for users as "usability" pain is trivial compared to the maximum "security" gain in authentication. Naturally, the hardware factor in the authentication received a widespread adoption amongst average users, as it is ergonomically less demanding than phone texts or authentication prompts. This ergonomic advantage in particular is essential for users who are blind or low vision, as their interaction with a phone is impractical. However, the "usability" for low vision or blind users pain might be much higher than an average well-bodied user for the same "security" gain. In an effort to learn more we conducted a usability assessment with ten low vision or blind users setting up the OnlyKey two-factor authentication key. First, the setup process was insurmountable for more than half of the participants, resulting in a situation where the hardware key was abandoned. Secondly, the lack of tactile orientation led participants to consider it as both impractical, and prone to difficulties locating or loosing it. We discuss the implications of our findings for future improvements in usable authentication for visually impaired users.