ZKTeco White LCD Series, Руководство пользователя

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2. Basic Concepts
Verification occurs when a user either enters an ID number or places a
finger on the fingerprint sensor, then input password for comparison
with the stored template.
2.3 Threshold
The Threshold establishes a balance between False Acceptance Rate
(FAR) and False Rejection Rate (FRR). FAR mean the probability that a
biometric system will incorrectly identify an individual or will fail to
reject an impostor. The rate given normally assumes FRR measure the
probability that a biometric system will fail to identify an enrolee, or
verify the legitimate claimed identity of an enrolee.
You can set the threshold to all users. For a user who’s the fingerprint
verification is difficult, you can adopt ID & Fingerprint verification (1:1
verification).
Raising the threshold increases security, while lowering it increases pass
rate. The correct balance is vital. For a user whose finger is worn or
injured, the threshold should be reduced.
Note
: FAR and FRR affect each other, if increases FAR then reduce
FRR. The default Threshold is 35, 1:1 matching Threshold is 15.
Table: Suggested Threshold Settings
FRR FAR 1:N 1:1
High Low 45 25
Middle Middle 35 15
Low High 25 10
2.4 User ID Numbers
In user fingerprint enrollment, the system assigned a User ID Number.
This ID number is used to call up the fingerprint template or password
each time that verification is requested.
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