Biometric locks

[Nickie]

I would like to know the benefits and the negatives for using biometric security system for auto, doors and computers, also is there different biometric technologies?

[mcm757207]

Advantages of biometric systems:

- Convenience (no keys to carry)
- Quality systems do exist which are fairly robust and secure (e.g., iris scanner, hand reader)
- "cool factor"

Disadvantages:

- Good systems are expensive
- There is often a careful balance between false-acceptance and false-rejection rates, this can be a fine line
- Inexpensive systems can be insecure (e.g., cheap finger print scanners)
- Older people can have difficulty with finger print scanners due to lack of finger prints

I tend to like systems that require pin + biometric data. In other words you have to enter a code before introducing your finger, hand, or eye. The only biometric systems I've seen for computers are finger print readers, which I'm not a huge fan of. I'd prefer to have some kind of secure credential-based system (such as a smart card or USB dongle of some kind).

Please note that we can't discuss the bypass of any of these systems here in these public forums.

[ChemicalRobot]

Here are some big disadvantages of fingerprint biometrics in my mind:

- You leave a copy of your "key" on many things that you touch
- If your fingerprint gets compromised, as in someone makes a copy that works with the lock, you cannot change it.
- Chances of getting your finger cut off rises

[mcm757207]

Many cheaper fingerprint scanners do only read the optical "image" of your finger print, but many quality ones actually check things like capacitance which are not left behind on things you touch.

[mh]

check things like capacitance

but the capacitance is a direct function of the optical image, so it's not difficult to imitate either. That just means that you cannot present a photograph of the finger only, but need some three-dimensional version, and that has been created with very simple methods before.

Cheers
mh

[mcm757207]

My understanding is that some readers measure the precise capacitance from a number of samples of the finger, which are unique to that individual. Perhaps I'm wrong? In other words, a particular part of the thumb might have so many farads (micro, nano, whatever) whereas the same place on your thumb might be more or less.

[ChemicalRobot]

My understanding is that some readers measure the precise capacitance from a number of samples of the finger, which are unique to that individual. Perhaps I'm wrong? In other words, a particular part of the thumb might have so many farads (micro, nano, whatever) whereas the same place on your thumb might be more or less.

If that's correct, then that is really cool; however, I'm skeptical. Is something like that really consistent enough that you could rely on it for biometrics? It seems that it would change far too frequently. What would keep the capacitance of a quadrant of my thumb from changing in a week or a month in the future?

[mcm757207]

I wish I had more information on this, but unfortunately I don't perhaps someone has heard of this besides me?

[globallockytoo]

Up until about 12 months ago I was selling the Bioaxxis Thumblock pictured here.

The manufacturer went belly up a number of months ago so the product is discontinued.

I found this product to be of reasonable quality (if not a little pricey), but did find that the fingerprint scanner sensitivity required to be reduced significantly to be able to work efficiently. This leads to obvious problems of insecurity. Just a few days ago, a client called looking for a solution to an issue he was encountering, where the master fingerprint (administrator) would not read properly to enable lock administration.

I was able to advise him luckily, but it was important that he had set up the unit to be bio or PIN or both configuration. This way he could enter the admin function using the administrator PIN and continue to update the unit.

He did tell me that most of it's users preferred to use the PIN access rather than the fingerprint, because of the failure rate of the reader was high.

I had installed the Bioaxxis BD1 deadbolt lock a few times, but found that almost anyone over the age of 55 experienced difficulties using it because the scanner could not properly read the image. This is a bad dilemma for users because fingerprint readers would have made life significantly easier for elder users, not having to remember PIN codes or hold loseable cards or keys.

[Shyfted]

Dont quote me on this (as my info may be a bit old) but when I was researching biometric systems the reason for it measuring resistance was to check that it is an actual finger on the scanner and not just a photocopy of the print. This was also the same for a moisture reading. So the original problem with bypassing these systems wasnt getting a copy of the valid finger print but using that print on a device that acts like a finger.

[mcm757207]

The system I was told about measured electrical capacitance, not resistance.