Really? Please describe such a system. Will it use a photograph of the fingerprint? A hash value? What hash? How do you deterministically arrive at the exact same one each time, or do you plan to "change the user name every single time" and in that case what is the actual persistent pointer to the account/person? Do you expect people to then use that name in conversation or when they think about it?
See, this makes no sense. That's not what "user names" are, it doesn't have any of the properties humans ascribe to them.
>similarly, lots of applications use the fingerprint as both username and password
Name them. Name one, for that matter.
You seem very, very confused about all this but at this point I really don't know how to make it any clearer for you.
you are defining terms one way and i have defined them another way (that's fine) so that is why we cannot come to agreement on any corollary.
the distinction is that you are sticking to the "formal" definitions, while i am using "functional" definitions.
we agree (troll test #1) that auth factors can come in 3 flavors (for the 100th time): something you know, something you have, and something you are. according to this definition, a fingerprint goes into one bucket ("are") and a password goes into another bucket ("know"). peachy. BUT, fingerprints are also something else: GREASE. grease left on a handrail doesnt fit into any of these buckets. that doesnt mean its not a fingerprint!
do you see the point? if you can appreciate that, and look at my comments through this lens, they might make sense. functionally, programmers are free to use "usernames" QUA "passwords" if they want to -- we can't just define that out of existence.
Names/User IDs are not equivalent to biometrics. Nor passwords. Nor tokens. They are symbols that exist to enhance human UX. That's it.
>remember the context of the comment you criticized is that there are vulnerabilities in biometric security
Yes, just like in every single form of authentication. Which is utterly irrelevant.
>so if you're merely saying (as i think you are) that biometrics make poor usernames, much as they make poor passwords
>that biometrics make better passwords than usernames, i'll reiterate: that's wrong.
These are utterly non-sensical statements. Biometrics are not user names (a public symbol) nor are they passwords ("something you know"), "poor" has nothing to do with it, they are one of the other two classes of unique authentication factors. They have their own strengths and weaknesses, and yield different practical results when combined with one (or both) of the other two in a multi-factor authentication system. And a biometric/token MF system can absolutely be superior in security for many common threat scenarios and use cases compared to passwords. Achieving good security requires intelligent deployment of all 3.