Factors that degrade the match distribution in iris biometrics

We consider three “accepted truths” about iris biometrics, involving pupildilation, contact lenses and template aging. We also consider a relatively ignoredissue that may arise in system interoperability. Experimental results from ourlaboratory demonstrate that the three accepted truths are not entirely true, and alsothat interoperability can involve subtle performance degradation. All four of theseproblems affect primarily the stability of the match, or authentic, distribution oftemplate comparison scores rather than the non-match, or imposter, distribution ofscores. In this sense, these results confirm the security of iris biometrics in anidentity verification scenario. We consider how these problems affect the usabilityand security of iris biometrics in large-scale applications, and suggest possibleremedies.