What False Acceptance and False Rejection Mean for Face ID?
What FAR means when it does not come with the corresponding FRR?
Answer: It means nothing.
According to some tech media¸the FAR (false acceptance rate) of iPhone X Face ID is said to be one millionth, which might be viewed as considerably better than the reported one 50,000th of Touch ID.
It is not the case, however. The fact is that which is better or worse can by no means be decided when the corresponding FRR (false rejection rates) of Face ID and Touch ID, which are in the trade-off relation with FAR, are not known. This crucial observation is seldom reported by major tech media. It is really sad to see the misguided tech media spreading the misguiding information in a huge scale.
The only meaningful fact that we can logically get confirmed by the trade-off between FAR and FRR is that the biometrics deployed with a password as a fallback means against false rejection would only provide the level of security lower than that of a password-only authentication.
Face ID, which brings down security as such, could be recommended only for those who want better convenience, as in the case of Touch ID. If recommended for better security, it would only get criminals and tyrants delighted.
Security professionals are expected to speak up.
30-second video - https://youtu.be/7UAgtPtmUbk