Date icon14 February 2019

Biometric access control systems: An Overview

Biometric access control

Introduction

Biometric access control systems are shaping the future of business security across the globe. With its faultless data gathering, identification and verification capabilities, biometric access control systems are crucial for the safeguarding and security of countless industries and sectors worldwide. Whilst at one time the characteristics of biometric access control wouldn’t have seemed out of place in the science fiction genre, its technology is improving security for businesses within countless industries of varying sizes and scales. The benefits of biometric access control are many and varied and are causing a significant stir across both high-risk security and smaller-scale organisations.

What is a biometric security system?

Biometrics is a method of establishing a person’s identity based on chemical, behavioural, or physical attributes of that person, and is relevant in large-scale identity management across a wide range of applications.

One of the most common uses for biometrics is providing access control for restricted facilities, areas, or equipment. Unlike code- and password-based systems or access card systems, which rely on information that can be forgotten or items that can be lost, biometrics techniques provide access based on who people are rather than what they have in their possession. 

In principle, a biometric system is a pattern recognition unit that gathers a specific type of biometric data from a person, focuses on a relevant feature of that data, compares that feature to a pre-set group of attributes in its database, and then performs an action based on the accuracy of the comparison. There are a variety of characteristics that can be used for biometric comparisons, such as fingerprints, irises, hand geometries, voice patterns, or DNA information, and although there are certain limitations to biometric capabilities, an effective system can precisely identify an individual based on these factors.

A standard biometric access control system is composed of four main types of components: a sensor device, a quality assessment unit, a feature comparison and matching unit, and a database.

The Sensor Device

A biometric reader or scanning device is used to obtain the necessary verification data from a person. For example, in fingerprint biometrics applications, an optical sensor is employed to produce an image of the ridge structure at a fingertip, and this image serves as the basis for further access control activity.  

The sensor unit forms the key interface between a user and a biometric access control system, making it important to minimize the rate of reading failure. The quality and usefulness of the data obtained through sensors often depends on camera characteristics because the majority of biometric data is composed of images, with the exception of audio-based systems, such as voice recognition, and chemically-based systems, such as odour identification.

Data Quality Assessment

In an access control system, the biometric data gathered by the sensor device must be evaluated to gauge whether it is suitable for processing. Typically, an algorithm designed for signal enhancement is applied to the data in order to improve its quality, but if the quality is insufficient for processing, the user may be asked to resubmit the data.

After processing, a specific set of features is selected from the overall data set to represent the qualifying identity trait. In fingerprint scanning, the relative positions of small ridge points can be extracted for use as a biometric measure. The feature set used for assessment and extraction is known as the biometric template, and is stored within the system’s database.

Comparison and Matching

After the feature set has been extracted from the gathered data, it is compared to the stored templates and matched with any identical points. The number of matching points between the input and the template provides a match score, which can fluctuate between readings depending on the quality of collected data. The matching device in a biometric system usually includes a decision-making apparatus that relies on the match score to either confirm a person’s identity or to determine the identity by correlating the score to a ranked list of possible identities stored in the database.

The System Database

A biometric system database stores all the information needed for processing biometric readings. When establishing access control parameters, the feature template is input into the database, sometimes along with biographical information specific to the user in order to enhance security levels.

A single biometric sample is often sufficient for extracting a user template, but in some cases, a biometric system can process multiple samples to form a mosaic representation. Some systems also store multiple templates to compensate for data variations that can arise from a single user. This method is often found in facial recognition biometrics, in which several templates are employed to account for alterations in facial poses relative to the sensor.  

What are the benefits of biometrics?  

A biometric system offers a higher level of identity security than a typical proximity-based Access Control system. This is because a biometric system uses an individual's unique biological information in order to verify and authenticate their identity. This is safer than using codes or access cards as these are easier to obtain. Biometric features can include fingerprint, retina, voice and facial recognition - all of which are extremely difficult to replicate.

Main advantages of biometric access control systems are:

  • It provides extra security. This type of access control is more secure, since the fingerprint or other biometric marker is a unique and unrepeatable characteristic in each person.
  • Low maintenance cost. Once the installation is completed, this type of access control has a much lower maintenance cost compared to other systems.
  • Doesn´t require additional devices for opening the door. With the biometric access control, there is no need for using traditional keys, switches and switching devices. Based on the identification of a unique characteristic of a person, it gets by without these elements, so that the situation of keys loss does not occur.  

The main disadvantages are:

  • A biometric system is less convenient in cases where the ‘users list’ changes frequently, as for example, in business centres or offices in which new staff enters periodically or when there are business visits.
  • The cost of installation is higher compared to other access control systems. Although the cost of maintenance is lower, the user will incur a higher initial investment.
  • Although it is not so common, in some cases, specific persons cannot be identified: 1 % of the population cannot be identified through a fingerprint.

Sometimes a combined identification system is used, for example, fingerprint and keypad, which offers great advantages. In other words, it is possible to take advantage of biometric access control and identification by codes, proximity or radio frequency (remote control) at the same time. The combination of different identification methods in a same access control system may increase the installation’s price but it provides more flexibility.

Transform your organisation today

Transform your organisation’s security today with TouchStar. We’re proud to deliver reliable and robust cutting edge biometric technology that transforms operations across numerous industries.   To find out more about our state of the art biometric technology solutions and how they can transform your organisation, get in touch today.