In biometric systems, the stored reference data comprise unique features of a data subject, which can contain sensitive data (i.e., ethnicity, diseases). If the reference data is compromised, biometric characteristics cannot be cancelled or replaced. Furthermore the amount of biometric characteristics of a single subject is limited. Multiple enrolments of biometric features for different applications can further lead to a Cross-Matching-Problem if those applications get linked with each other. As a consequence for a privacy preserving biometric technology, the adequate protection of the biometric reference data is indispensable. With biometric template protection procedures, the biometric information cannot be reconstructed out of the reference data. These technologies enable an inherent secure biometric authentication and thereby a new and simplified usage of biometrics.