Biometric Authentication

Introduction

For ages, humans recognized themselves according to different characteristics (appearance, behavior…). Biometrics is a well known technique to identify an individual or verify its identity; as, for example, fingerprints have been used for more than 100 years to identify one criminal. With computers, this analysis can be realized very quickly and with a higher reliability.

Biometrics has many applications: site monitoring (Bird, Masoud, Papanikolopoulos, & Isaacs, 2005), e-commerce (Jain & Pankanti, 2006)… The main benefits of biometrics are to provide better security and to facilitate the authentication process for a user. For example, it can be easy to obtain the password of a user, but it is more difficult to look like the user if a face recognition system is used for the user verification. Biometrics can also provide many advantages for particular applications. Indeed, biometric authentication can be realized in a contactless way that could be important for cultural aspects or reasons of hygiene. For all these motivations, biometrics is an emergent technology that could be more present in our daily life.

The goal of this chapter is to make an overview of biometrics. We focus on the authentication process, whose goal is to verify the identity of an individual. Ideal biometric information must have multiple properties:

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  Universality: all individuals must be characterized by this information;

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  Uniqueness: this information must as dissimilar as possible for two different persons;

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  Permanency: it should be present during the whole life of an individual;

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  Collectability: it can be measured (in a easy way);

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  Acceptability: it concerns the possibility of a real use by users.

The plan of this chapter is given below. The background part presents the different biometric modalities studied in the research labs and used in real conditions. The main thrust of this chapter is an analysis of the benefits and limitations of biometric authentication. We present also the general architecture of a biometric system. Future trends stress the different research topics that should be treated to improve the biometric authentication. It concerns the combination of different biometric systems and their performance evaluation. We conclude by resuming the main aspects of this domain.

Background

We detail, in this section, the different biometric modalities from the state of the art that can be used for the authentication process. Figure 1 illustrates the different types of biometric information. Biological analysis exploits some information that is present for any alive mammal (DNA, blood…). The behavioral analysis is specific to a human being and characterizes the way an individual makes some daily tasks (gait, talking…). Last, morphological analysis uses some information on how we look (for another individual or for a particular sensor).

Figure 1.

Different biometric information in the state of the art

Biological Analysis

As mentioned previously, biological biometric information can be extracted from any human being (see Figure 2). Generally, this information is not very easy to obtain. Some particular sensors are needed and the extraction of the biometric information can be quite long. For example, the DNA analysis with the most recent research techniques is possible in a few hours. We can cite the blood analysis that can only differentiate two individuals with different Rhesus groups. We focus, in this chapter, on recent biological biometrics.

Figure 2.

Some illustrations of the biological analysis (K. Phua et al., 2007)