

Identity and Authentication are Separate Things: Why Fingerprints Shouldn't be Passwords - mdasen
http://technet.microsoft.com/en-us/library/cc512578.aspx

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te_platt
I worked for a fingerprint recognition startup in the early 90's and then
later on my own in the early 00's. My quick summary: Fingerprints are
effectively useless for security.

Technology reasons: Some systems are better than others but none is perfect.
False positives and false negatives are part of the system. The worst part is
not that everyone is affected .001% of the time but that a few people (usually
older people or people who work with their hands) are affected most of the
time.

Security reasons: As mentioned in the article, fingerprints need to be treated
as public information. You leave them everywhere and are not that tricky to
copy. Mythbusters did a nice episode on this. Also, you can't change them once
they've been compromised. For a while I worked in a Top-Secret environment and
we didn't use fingerprints exactly because they weren't secure and, worse,
could give a false sense of security.

Convenience reasons: Given that you shouldn't use them for high security
systems what about low security systems. I hacked a fingerprint reader onto my
car and thought it was so cool. I took it to a local car dealer to get his
impression. He showed me a new BMW that used a proximity card to unlock the
car - blew my system away for convenience.

Societal reasons: There are a lot of people who will just never feel
comfortable giving their fingerprint to a computer. The stigma is that's what
criminals do. Most common lame joke when doing a fingerprint demo: "You gonna
give that to the FBI?, ha ha ha".

Now one of you may come up with a way around all these issues. I know you can
get a fingerprint reader on your laptop. I used to think it was pretty
impressive when I had one of the first. Eventually the novelty wore off and
the inconvenience factors led me to stop using it. I'd like to hear if someone
has had more success than I did.

~~~
gravitycop
What is wrong with combining diverse metrics (fingerprint, iris, retina,
height, weight, pulse, body-temp, voiceprint, gait, etc.)?

~~~
te_platt
Nothing is "wrong" with doing that. What advantage to you hope to get by
combining metrics?

~~~
gravitycop
>>> False positives and false negatives are part of the system.

>> What is wrong with combining diverse metrics

> What advantage to you hope to get by combining metrics?

Reduction of false positives and false negatives, i.e. increased recognition-
accuracy.

~~~
statictype
The problem with using biometrics at all is that you're conflating
authorization with authentication. Those are fundamentally different (at least
in the society we live in).

Biometrics are used for authentication - proving who you are (whether it works
and can be duplicated is a different issue).Useful for a passport or driver's
license.

Car keys, passwords, ATM pin numbers are a form of authorization.

For example, you may want to let your daughter withdraw money with your card
or use your car. Biometrics can't be used for that purpose.

~~~
gravitycop
_For example, you may want to let your daughter withdraw money with your card_

That would be an example of a generic (unpersonalized) key. It's a poor
example because:

1\. People don't lend out ATM cards.

2\. Why wouldn't I simply transfer funds into her account?

3\. Physical cash is unlikely to exist for much longer.

 _or use your car._

The generic (unpersonalized) key, again. Why wouldn't I simply tell my car to
let my daughter use it?

~~~
statictype
1) Not even to their own family?

2) Because I had to go to shop to pick up some Foo and meanwhile wanted her to
get some money from the machine that was next door..?

3) um, ok. If you say so.

There are tons of reasons. I'm talking about how the world works right now.
Not a hypothetical world that may or may not exist in the future.

~~~
gravitycop
_Because I had to go to shop to pick up some Foo and meanwhile wanted her to
get some money from the machine that was next door_

If you were buying something from a physical shop, you wouldn't need money
from a machine next door, because shops can give cash at the register from the
customer's bank account.
[http://www.google.com/search?q=%22would+you+like+cash+with+t...](http://www.google.com/search?q=%22would+you+like+cash+with+that%22)

~~~
statictype
Man, you're really reaching. Forget it, you win.

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gcv
Early in the article, the author says that a card is something you have, a
public identifying token, and, since it can be stolen, it should require
something to unlock it. Later, in the hospital example, he suggests that a
private key stored on a smartcard works as an authentication token. Seems to
me that a card with a private key can be stolen just as easily as an ATM card.

~~~
eru
Yes. But they are used in different contexts.

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okeumeni
Finger print should not be password for a simple reason, it's going to be
easier with technology to steal finger print; unlike password you can't change
it : (. I saw and read document on technology available to transfer finger
print into glove like molds. Finger print will eventually become Identity
theft next biggest challenge.

~~~
ricree
Agreed. Unless phishing somehow becomes a solved problem which I don't see
happening, then biometric authentication should never become mainstream. As it
stands now, successful phishing attacks range in severity from mild annoyances
to somewhat harmful. In all cases, though, they can ultimately be contained so
that people can move on with their life. Biometric id, on the other hand,
can't be readily changed.

~~~
gravitycop
Has anything other than biometric authentication been used as ultimate
identification for the past 100,000 years? What would you replace this
presently-ubiquitous identity system with?

~~~
wmf
What humans do to recognize each other is totally different from "biometric
authentication" as the term is used in computer security.

~~~
gravitycop
_What humans do to recognize each other is totally different from "biometric
authentication" as the term is used in computer security._

How is it different? Your acquaintances do not sense general factors of
Wmfness based on your height, build, voice, accent, verbal expressions, face,
hair-color, hair-style, hair-length, facial hair, clothes, accessories, gait,
hand-size, foot-size, body odor, etc.?

~~~
ricree
The difference is the ability to duplicate that information. For normal face
to face recognition, it is reliable because it is impossible to totally
duplicate another person even if you are given complete knowledge of every
identifiable feature of that person.

Electronic biometric identification, on the other hand, can be flawlessly
duplicated provided that you have accurate information on the aspect of the
person being used to id them, as well as the method of transmitting the data.

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CalmQuiet
This might begin a useful discussion of the identity-authentication
distinction and how it should inform web development projects. I'm voting it
up in the hopes that people more in the know will _update_ this Microsoft
perspective (the article is dated February 2006). I'm a noob on such issues.
Maybe some YHackers would like to link to some 2009-ish offerings about it?

~~~
aneesh
The way you might implement these abstract concepts in an application might
have changed over the past 3 years, but the concepts themselves are still
pretty applicable.

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mhb
I continue to be amazed that physical credit cards don't require any
authentication. Losing one is like losing (someone else's) cash. Why don't the
stores or banks require a PIN number when using a credit card?

~~~
aneesh
Because (rightly or wrongly), the stores have concluded that the _gain_ from
making it so easy to buy something with a credit card is more than the _loss_
they face from the fraud that you describe.

