False Acceptance

When a false acceptance occurs, a system mistakes an unauthorized user as an authorized user, wrongfully allowing access. For this reason, the FAR (false acceptance rate) is very essential in any biometric system. For instance, if the FAR is 10 percent, an average of one out of every ten unauthorized users attempting to access a system may be recognized as authorized. A security system’s FAR can be defined as the number of false acceptances divided by the number of authorization attempts. A false acceptance is generally considered to be one of the most serious of all biometric security flaws as it grants access to unauthorized users, access to systems that are essentially attempting to keep them away. Examples of a false acceptance may occur in time and attendance systems. This would be when a system registers a punch on a time clock with someone using another employee’s credentials for validation.