Furthermore , there may be problems with extracting the biometric traits -- for example system or environmental problems .
Accurately functioning systems rely on two fundamental premises -- the permanence and uniqueness of the relevant biometric trait , both of which are not certain .
There may be problems with extracting the biometric traits -- for example system or environmental problems .
Accurately functioning systems rely on two fundamental premises -- the permanence and uniqueness of the relevant biometric trait , both of which are not certain .