What Does Passive Biometrics Mean?
In passive biometrics, systems are able to authenticate a user without any explicit user activity or input. This is often done through a diversity of passive inputs, including data sets that are generated by monitoring the user in real time.
Techopedia Explains Passive Biometrics
For example, the use of passive biometrics might involve visual or sensor monitoring to see how a user moves, how he or she holds a device, and how he or she speaks, as well as identifying ambient information like body temperature and anatomical contours or facial recognition.
By contrast, active biometrics, as the traditional form of biometric authentication, requires some user input. A good example of active biometrics is the thumbprint pad, where the user puts their thumb on a reader, and the machine authenticates through the unique thumbprint analysis.
Passive biometrics has the benefit of being able to authenticate without any user-generated event, but the challenge is to make that process absolutely foolproof, which is generally more difficult than with active biometrics.