Uniqueness of fingerprints?
Posted Apr 6, 2008 11:32 UTC (Sun) by
man_ls (subscriber, #15091)
In reply to:
Uniqueness of fingerprints? by ayeomans
Parent article:
Biometrics for identification
Hmmm... doesn't the principle behind the Birthday paradox apply here? Even if there are 366 days in a year, the probability of two people having the same birthday reach 0.5 with a group of only 23 people. Therefore you would only need roughly the square root of the number of possibilities to find a collision.
With 120 bits you are still safe, since the world population is about 2^32. But the security factor is not as high as it would seem. Surely we don't expect all values to be as likely, as with birthdays; if they tend to cluster around certain values (some kinds of fingerprint configurations are more probable than others) then collisions become increasingly likely.
(
Log in to post comments)