ZK Technology F707, Руководство пользователя

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60
Match Threshold Levels
The Match Threshold is the degree to which a verification is performed to
ensure that the user is who he/she claims to be.
The Match Threshold Levels establishes a balance between False
Acceptance Rate (FAR) and False Rejection Rate (FRR). FAR measures
how often a non-authorized user is falsely recognized and granted access
to the system. FRR measures how often an enrolled and authorized user,
who should be granted access to the system, is denied on the basis that the
system did not recognize him/her.
Note that you
cannot
set match threshold levels on a
per user
basis. The
threshold-setting is universal
, for the ENTIRE user-population.
If too many users are experiencing difficulty having his/her fingerprint(s)
read, we recommend using 1:1 matching (i.e. User first enters his/her User
ID, and then places his/her finger on the sensor for verification).
Raising the threshold increases security, while lowering it increases
throughput. Based on the quality of the fingerprints of the users, you need
to strike a correct balance.
So if too many users have fingerprint(s) having difficulty being read, the
match threshold level can (and should) be reduced.
Table
1—1
Suggested Match Threshold Settings
FRR FAR One-to-many One-to-one
High Low 45 25
Middle Middle 35 15
Low High 25 10