Tracking Code-based Verification-Design and Evaluation

Tomitigate security risks of Internet voting, techniques for verifiability have been developed, allowing the voters to verify that their cast vote has not been manipulated. One such technique is the use of tracking codes, which does not rely on complex cryptographic mechanisms, and therefore is often assumed to be more intuitive for the voters. However, no systematic evaluation of the usability, verification efficacy, and perceived trustworthiness of these systems has yet been conducted. Our contribution evaluates two variants of a tracking code-based system in a user study (N = 306), testing both of the variants in the absence of vote manipulations as well as using different simulated tactics of vote manipulation. We conclude that both of our proposed variants are perceived as easy to use, transparent, and trustworthy in the absence of vote manipulation. However, we found varying rates of verification efficacy based on the vote manipulation tactic, manipulation with detection rates ranging from 0% to 76%. We conclude that using tracking codes can be a viable approach. At the same time, more awareness of potential manipulations needs to be raised to achieve the required security level, irrespective of the verification technique in place.