Honeywell VISTA Series - Basic Concepts; User Enrollment Process

HoneywellVISTASeriesProductsUserManual
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2BasicConcepts
Thissectionintroducesthedefinitionsanddescriptionsofthefollowingbasicconcepts:
Ø Userenrollment
Ø Userverification
Ø Matchthreshold
Ø UserID
Ø Authorityclass
ThemostimportanttwofunctionssupportedbyCAFP100Fxxseriesareuserenrollmentandverification.
2.1UserEnrollment
A usercanenrollupto10differentfingerprintsusingoneIDnumbertohavemultipleverificati onselections.
Theoreticallyallthefingersofauserneedtobeenrolledsothattheusercanstillperformfingerprintmatching
evenif oneormoreofhis/herfingersgetcutordamaged.Generallyi tisrecommendedthatausershallenroll
atleasttwofingerprints,forexampl e, theindexfingersofbothhands,sothat theusercanuseanyofthe
enrolledfingerprintsforrecognitionevenifhe/sheforgetswhichfingerprinthasbeenenrolled.
2.2UserVerification
When a user enters a password after placing his/her finger on the f ingerprint reader, or scans his/her
fingerprintafterenteringanIDnumber,theCAFP100FxxFRTcomparesthenewlyscannedfingerprintwith
afingerprintstoredintemplate.ThefingerprinttemplateisusedtochecktheuserID.Ifauserenrollshis/her
fingerprints on an FRT, the user can keep att endance records on this FRTthrough fingerprint verification
whichtakesabout2seconds.Uponverification,thesystemdisplaysapromptaboutwhethertheverification
succeedsornotandthenstoresthesuccessfulmatchingrecordintheCAFP100FxxFRT.
2.3MatchThreshold
The match threshold is set to achieve a tradeoff between the possibilities of false rejecti on and false
acceptance.ThefalseacceptancemeansthefingerprintrecognitiondevicemistakesthefingerprintofuserA
fort hatofuserB,whilethefalserejectionmeansthefingerprintrecognitiondevicerefusestorecognizean
enrolledfingerprint.
Youcansetamatchthresholdforallusers.Forfingerprintsthatfailtopasstheverification,youcanadoptthe
"ID+Fingerprint"verificationmode(thatis,1:1match)sothatthesystemadoptsthedatasetin1:1match
thresholdwhenmatchingthefingerprints.
Ifauser’sfingersareseverelywornoutordamaged,lowerthematchthreshold(seeTable31).
Note:Thefalseacceptancerate(FAR)andfalserejectionrate(FRR)m utuallyinfluenceeachother.Reducing
theFARwillincreasetheFRR,andviceversa.Thedefaultmatchthresholdis35andthedefault1:1match
thresholdis15.Tabl e31liststhesettingsofmatchthresholdsindifferentscenarios.
MatchThreshold
Matchthreshold
FRR FAR
1:N 1:1
High Low 45 25
Medium Medium 35 15
Low High 25 10
2.4UserI D
Whenenrollingfingerprints,auserwillbeallocatedwithanunusedID.Whentheuserstartstoverif yhis/her
identity,thisIDisusedtoassociatethefingerprintfeaturetemplateorpassword.