Abstract or Summary:
In the real world we do authentication hundreds of times a day with little effort and strong confidence. We believe that the digital world can and should catch up. The focus of this paper is about authentication for critical applications. Specifically, it is about the fundamentals for evaluating whether or not someone is who they say they are by using combinations of multiple meaningful and measurable input factors. We present a "gold standard" for authentication that builds from what we naturally and effortlessly do everyday in a face-to-face meeting. We also consider how such authentication systems can enable resilience to users under duress. This work differs from much of the other work in authentication first by focusing on authentication techniques that provide meaningful measures of confidence in identity and also by using a multifaceted approach that comprehensively integrates multiple factors into a continuous authentication system, without adding burdensome overhead to users.