Electronic identification methods.
Electronic identification methods.
Electronic methods of human identification, used in systems for ensuring authorized access to protected areas of the territory, as well as to material and information resources, are currently widespread.
The article discusses the design features of various identification methods, information about which was obtained from various publications and advertising materials of an informational nature. Considering that work is currently underway to create a Russian GOST for access control and management systems, the author considered it necessary to use in the article the basic terms set out in the draft GOST.
Any territory where a pass regime is provided is simply unthinkable without checkpoints. The simplest, but at the same time not always rational, is the use of a security guard-controller.
Access control and management systems (ACMS), which are now widely used, implement a higher quality level of access control, including eliminating or sharply reducing the influence of the «human factor» of the security guard, for example, fatigue, absent-mindedness, etc.
The use of electronic devices for identification in ACS, that is, the procedure for comparing the presented individual characteristics with the standard stored in the system, has necessitated the use of new methods of coding and «presentation» to the system of identification features that determine a person's identity.
Identification features entered into the system may be characterized by both biometric characteristics of a person and a multi-code combination that conditionally characterizes a specific person.
Identification features are entered into the system either directly, using biometric terminals and code-setting panels, or using material carriers (identifiers) and corresponding reading devices (readers). An identifier may be made, for example, in the form of a plastic card with coded information characterizing the identification features.
Depending on the method of entering information into the ACS, the following types of peripheral devices are currently used:
— biometric terminals and code-setting panels that provide direct entry of identification features;
— reading devices (readers) that provide entry of coded information characterizing identification features from identifiers.
BIOMETRIC TERMINALS
In such systems, so-called biometric characteristics are used as identification features.
There is a whole group of protected areas, high requirements for the access control system in which cannot be ensured by using identifiers or entering a code combination on the corresponding code panel. In such cases, so-called biometric characteristics are used as identification parameters.
These are unique biological, physiological characteristics of a person, unambiguously certifying his identity.
Currently, fingerprints, finger geometry, handwriting dynamics, vascular network pattern of the fundus and other similar parameters are used as carriers of biometric characteristics.
The system, based on the identifier presented by the user, finds in its memory the reference biometric characteristics previously recorded during the initial registration procedure. The user presents the corresponding personal biometric parameters to the system for reading. After comparing the received and reference parameters, the system makes a decision on granting or denying access. To implement such a comprehensive verification procedure, biometric terminals, along with the actual biometric characteristic meters, are equipped with the corresponding readers of identification parameters from material carriers (identifiers or code device).
When considering biometric methods, it should be borne in mind that in biometrics it is absolutely impossible for reference samples and newly obtained results to give a complete match. This is true for all biometric characteristics, for example, fingerprints or signature dynamics. For example, fingers cannot always be placed in the same position, at the same angle or with the same pressure as during reference reading. Despite the fact that the biometric process does not give an exact match of characteristics, it can be said that such a process gives an extremely high level of identification accuracy.
A noticeable revival in the biometric systems market occurred after the appearance of fairly powerful and at the same time inexpensive 16-bit microprocessors and the creation of effective algorithms for processing biometric information.
Abroad, biometric terminals are currently being developed and offered for sale mainly by US firms and a small number of firms in England.
As an example, let us consider some of the hardware implementation options for individual biometric control methods that are appearing on the domestic market.
BIOMETRIC FINGERPRINT CONTROL
The principle of fingerprint control is based on two main qualities inherent in the pattern of human finger skin:
— stability throughout a person’s life;
— uniqueness, which means that no two people have the same pattern.
Fingerprint recognition is based on the analysis of the distribution of special points of the pattern of the skin of the fingers. Special contact sensors of various types are used to remove fingerprints in real time. Fingerprint identification systems have been produced for almost two decades. However, due to the successes achieved in the field of computer fingerprint recognition in recent years, the number of companies producing biometric terminals based on dactyloscopy has increased significantly.
When speaking about the reliability and validity of using fingerprints as identification characteristics, it is also necessary to consider the possibility of copying them and using them by other persons to gain unauthorized access. As one of the possibilities for «deceiving» a biometric terminal, experts point out the possibility of making an artificial hand with the required fingerprints or removing the «original» from the legal owner. But if there is a fundamental way of deception, then the fight against such falsification is also carried out. For this purpose, special equipment is included in the biometric terminal, which allows to distinguish «living» skin from «non-living».
An example of such equipment can be:
An infrared detector that allows you to record thermal radiation from a hand or finger;
— photoplethysmograph, which detects changes in the reflection of light from the surface of the blood flow.
Another well-known method of falsification is the direct application of the pattern of the legitimate user's skin on the hands of the intruder using special films. However, in this case it is necessary to obtain high-quality fingerprints of the legitimate user, and in a certain sequence (if the system is configured to check not one, but two fingers in turn). In addition, the «intruder», as discussed above, when passing through the checkpoint will be required to present the system with the identifier or personal code of the true owner. The need for the «intruder» to comply with a set of conditions makes such an attempt very problematic.
It should be noted that a number of biometric control devices require direct contact of the sensor elements of the device with the surface of the human body. This imposes certain hygienic requirements on the product and necessitates the use of periodically updated special disinfectants in the contact zone.
BIOMETRIC CONTROL BY HANDWRITING
The basis of the biometric control method by handwriting is the individuality and stability over time of the dynamics (speed, pressure, etc.) of each person's handwriting. But a person is characterized by some variation in handwriting characteristics even when writing the same text. In order to take this variation into account when forming a «standard», the user writes out his signature several times during the initial registration. The signature is made with an ordinary ballpoint pen or pencil on a special touch panel included in the terminal. The method of confirming one's identity by signing is familiar and comfortable for a person; it does not cause technological and hygienic discomfort. At the same time, forging the dynamics of a signature, and not its drawing, is a rather difficult process.
BIOMETRIC CONTROL BY THE DRAWING OF THE EYE FUND
The uniqueness of the fundus pattern, formed in particular by the network of blood vessels, is stable over time for each person. Moreover, this pattern differs even in twins. Therefore, it can be used with great success for personal identification.
Information is collected from the fundus by scanning in the optical range with radiation intensity safe for the eyes. In terms of protection against counterfeiting, this method compares favorably with all other biometric terminals, in particular, because specific attributes are used as identification characteristics, which are almost impossible to counterfeit to deceive the system during verification. For example, the dynamics of the painting is very difficult, but in principle it is possible to forge. It is also possible to create a copy of the skin pattern, but it is really possible to replace the eye only by means of a surgical operation, but it is unlikely that anyone would be willing to experiment with their eyes.
Devices using the biometric control method have a fairly high degree of identification reliability. At the same time, the cost of such devices is very high.
The current active implementation of access control and management systems in the market sphere, including in Russian production and commercial structures, is characterized by the widespread use of plastic identification cards and code-setting panels in ACS, using a multi-bit personal code as identification characteristics.