What does the Crossover Error Rate (CER) indicate in a biometric system?

The Crossover Error Rate (CER) is a critical metric in the evaluation of biometric systems, representing the point at which the false acceptance rate (FAR) and the false rejection rate (FRR) are equal. This means that at the CER, the likelihood of incorrectly accepting a non-matching fingerprint (or other biometric data) is the same as the likelihood of incorrectly rejecting a matching one.

In biometric system assessments, achieving a low CER is desirable because it indicates that the system is accurately distinguishing between authorized and unauthorized users while minimizing both types of errors. A lower CER suggests a higher reliability of the biometric system in identifying individuals correctly. Thus, it serves as a useful benchmark for comparing the effectiveness of different biometric technologies or configurations, with the goal of finding a balance that satisfies user needs for security and usability.

The other options do not capture the essence of what CER measures. The maximum acceptance time relates to system responsiveness and not error rates; enrollment error rate pertains to initial data capturing inaccuracies, and the simultaneous processing of users addresses system throughput rather than error rates. Understanding the CER is essential for any effective identity and access management strategy involving biometrics.