As biometric applications move into the public sector, learn how they can be applied.

Biometric identification and verification systems will be increasingly used in the future. One reason is that in a society that is increasingly mobile, flexible and digital, there is a need for more efficient identification systems. A second reason is that criminals have acquired great expertise in circumventing the old identification systems.

In addition, as biometric technologies become better, cheaper, more reliable and more convenient, they will increasingly be implemented in other environments such the everyday life, in businesses, at home, in schools, and in other public sectors.

This can be labeled the "diffusion effect". In practical terms, biometrics will be used mainly for four purposes, law enforcement, physical access control (including border control), logical access control and convenience.

Traditionally, the most widespread use of biometric applications has been in law enforcement. Fingerprints have been used since the 19th century, and more recently DNA analysis has become routine in assisting criminal investigations.

It is due to this history that many citizens associate enrolment in biometric systems with criminals and hence tend to resent it. Therefore, it is important to underline that law enforcement is only one among many possible application areas.

Law enforcement is however until now the only area where large-scale applications have been in use for some time. Physical access control based on biometrics has so far been mostly limited to private companies' premises, i.e. small-scale applications. However, there are a number of trials underway or recently completed, many of which are at airports, which have tested biometrics access with large numbers of customers, rather than employees.

Most importantly, on the government side the integration of biometrics into passports and visas will for the first time create truly large-scale physical access control applications. Logical access control (in particular online identity) is forecast to be a fast growing use of biometrics. With more and more transactions such as e-banking, e-commerce and e-government taking place online, biometrics offer a promising way of establishing secure identities especially when face-to-face contact between the participants in the transaction is not possible.

This is particularly important for high-value financial transactions and for the transmission of confidential data (for example tax returns). Logical access control will also include access to entitlements offline, such as social security pay-outs.

Finally, convenience applications include all uses of biometrics where individuals voluntarily participate because they find it advantageous to do so. This would include ambient intelligence applications such as personally-adjusted home lighting or e-toys, but also participation in biometric applications offered by private actors, such as shops, sports clubs or other, where participation is not mandatory.

These classifications are useful for analysis. However, while they are clearly distinct in theory, in practice the different structural and practical applications tend to be applied jointly. For example, in functional terms law enforcement has used biometric identification for several purposes: firstly, to verify the presence of a suspected individual at a scene of crime; secondly, to identify which among several individuals was present at a scene of crime; thirdly, to create a profile of an unknown individual known to have been present at a scene of crime.

In other words, it is used for verification, identification and screening. Other applications, for instance e-health, may combine physical access control to the operating theatre with strict logical control of access to medical data.