uTouch User Manual
v1.6
12
7.1
Creating a new user
Creating a new user is plain simple – when the list of users is shown, just touch the plus (
“+”
)
label. When you touch this symbol, a keyboard is shown, and this is where you are supposed to enter
the PIN of the person which will be added to the system. The PIN is a unique number of that person
in the system, and it can be the existing personal ID number of the person, or a custom number
defined by the installer.
After choosing the pin and touching the checkmark symbol, the following screen is shown:
In this screen you also need to choose level of security (FAR). This is only important if the
“Fingerprint 1:1” type is used. When using “Fingerprint 1:N (AFIS)”, default security rating is used by
default.
7.1.1
About security - FAR and FRR
FAR (False Acceptance Ratio) is a value stating probability of false acceptance of a fingerprint
template presented on the sensor. The lower the value, the higher the security.
The tradeoff here is the fact that, if you decrease FAR, you also increase FRR (False Rejection
Ratio) which increases the probability of unit rejecting the fingerprint template of a person who is
actually authorized to access the unit. These two figures are directly connected, and choosing the
right value depends on the person and the application of the unit.
If there is need for lower security (time and attendance, public kiosks etc.) security level can
be lower (that means, FAR value needs to be higher) to increase passage speed. If there is need for
higher security (access control to server rooms, cash rooms, vaults, etc.) FAR value needs to be
lower.
7.1.2
Choosing proper FAR value
As already stated, choosing proper value depends on the application of the unit and the
person whose finger is enrolled to the unit. If a certain person has problems enrolling (various skin
conditions like hands being too sweaty, too dry, cuts on fingertips, wrinkles, or some other condition)
or you need to enroll the person often, maybe it would be better to decrease security for that person
alone. Of course, if the application allows you to lower the security.
There is not much to be concerned here, though – even in the most unsecure setting, there is
a 0,01% chance (1/10.000) that the unauthorized person will gain access. The most secure setting is
0,000000001% chance (1/100.000.000) of false acceptance, but be prepared for more common false
rejection of enrolled people.
