Biometric time clock

From Wikipedia, the free encyclopedia

Biometric time clocks are a class of employee time clock that detect a persons biological attributes to identify them. Examples of this are the hand print clock, which detects the overall attributes of a person's hand, fingerprint clock, and retina scanning clock.

There are two major issues faced by many companies with traditional clocking cards or swipe cards
(i) People clocking their friends in and out "Buddy punching", and,
(ii) People losing cards.


Contents

[edit] What is biometrics?

Biometrics is the measurement of one or more physical characteristics of an individual so that they may be identified. The characteristics, therefore, need to be unique for each individual.

There are two ways this information can be used. It can either: -
(i) Identify the individual, by comparing the sample with an entire database of samples, or,
(ii) It can verify another piece of information (such as a swipecard or a unique reference number typed at a keypad) by comparing the sample supplied with other samples in a database.

For biometric data to be useful it must meet certain criteria. It must be: -
• Easy to collect the data and compare it with the database,
• Universal - everyone must have one,
• Different for all employees,
• Unchanging over time.

[edit] History of Biometrics

The oldest, best-known and most widespread form of biometric recognition is the fingerprint. Fingerprints have been found on Babylonian commercial transactions from around 5000 years ago, and on Chinese seals from the 7th century AD, and in the 14th century, a Persian doctor noted that no two fingerprints were the same.

The earliest fingerprint recognition terminals appeared in the mid- 1970s, and the first commercial products appeared in the early 1980s. These terminals were initially used for access control and time management for governmental organisations such as prisons. Fingerprints continue to be the main biometric technology in terms of market share.

[edit] What type of biometric system is the best?

Different sorts of biometric technology are suited to different environments, and each type of technology has advantages and disadvantages which may be acceptable or unacceptable depending on the way it is to be used. Other factors such as cost, ease of use and employee acceptability (perceived intrusiveness) must be taken into account.

A biometric system must be able to adapt to permanent and temporary changes for the employee using it. For example, growing a beard or cutting a finger should not prevent someone clocking in at work despite the change in the physical appearance of the body being measured.

Authentication systems using a physical object (such as a swipe card) or a password give a Yes / No answer. The person with the card is 0% or 100% the person they claim to be. However, biometric information is never perfect and gives answers between 0% and 100%, with 100% never being reached. This variation is related to the quality of the biometric information being captured, so it is necessary to set threshold limits of what is acceptable. These thresholds may be different for each person.

Biometric systems are measured (confusingly in double-negatives) for accuracy by comparing the rate at which people are falsely rejected against the rate at which people are falsely accepted. A low “false acceptance” rate is necessary where security is paramount (for example if the time and attendance system is connected to an access control system).

However a low “false rejection” rate is necessary where convenience and ease of use are more important factors. These two factors need to be balanced and borne in mind when selecting a biometric system. These rates will depend not only on the quality of the system, but also on the level of security set when enrolling employees.

[edit] Different Biometric Technologies

Fingerprints

The minutiae of a fingerprint are the particular features of the ridges and furrows on the finger, and form a pattern of where ridges end and join. Police in most countries have rules stipulating how many of these minutiae have to match up for the identification to be positive, typically somewhere between 8 and 17 points, with no minutiae at all being found in the wrong places.

Key advantages are: -

  • It is technically the most tested technology
  • It is the best known by the general public
  • The relatively small size of the reader means it can be

integrated into many various applications

  • The reasonably low cost of the readers
  • The data is processed quickly
  • There is a good compromise between false rejects and false

accepts

  • The system can identify as well as authenticate employees


Key disadvantages are:

  • Fingerprint technology is associated with law enforcement and

the security services (CSI etc)

  • There is a need for the co-operation of the user, i.e. putting

the correct finger in the correct position

  • Although most readers only accept living fingers, a small

minority can accept a moulding of a finger or a cut finger

  • The reader (sensor) can be exposed, and may be damaged in

public areas or if located outside a building.

Hand Geometry

Hand geometry is the measurement of the outline shape of a person’s hand, and is the second most common type of biometric recognition system. The shape of the hand is scanned in, and parameters such as the length of the fingers, their thickness and their relative position are extracted from the image and are compared with the database in the same way as fingerprints. This type of biometrics is however susceptible to changes in the hand related to ageing. Hand geometry biometrics is simple to implement, it is well accepted by employees clocking in and out. It is used to authenticate individuals and has proved to be reliable. It is particularly useful for environments where employees handle corrosive substances or are engaged in other tasks that will cause their fingerprints to degrade.

Key advantages are: -

  • It is well accepted by users
  • It is very simple to use
  • It is fairly inexpensive
  • It is immaterial whether fingers and hands are wet or dirty


Key disadvantages are: -

  • The unit is very large
  • There is a risk of false acceptance for members of the same

family

  • Recognition can be corrupted by ageing or injury.


Facial Recognition

Facial recognition systems work by measuring the distance between the eyes, the spacing of the nostrils, the width of the mouth and so on. This method must be able to take into account certain changes to the face, such as wearing glasses or growing a beard, and the environment, which may be affected by lighting. It is impossible to tell identical twins apart.

This technology tends to be used in fields such as low-security access control and cash machines which already have a camera in place.

Key advantages are: -

  • It is well accepted by the public
  • There is no physical contact with any technology or units


Key disadvantages are: -

  • Reader units are sensitive to factors such as lighting, position,

facial expression

  • Readers cannot differentiate between identical twins
  • Reader units are sensitive to changes like beards, glasses,

piercing, surgery etc.

Voice Recognition
This should perhaps be called speaker recognition because it is not the interpretation of the words spoken, which is fairly common in automated telephone systems, but the recognition of the person saying it.
Each person is recorded and the sounds are measured for their frequency, intensity and tone. The computer tries to take into account distortions related to the equipment used, so the voice can be recognised, for example over a telephone or radio transmitter. Voice recognition has the advantage of being well accepted by users. It tends currently to be used for telephone transactions where the voice is only biometric information available.

Key advantages are: -

  • It is easier to protect the sensor than in other technologies

because it is generally located behind a grille

  • Regardless of any protestations from Rory Bremner or Alistair

McGowan, it is impossible to imitate another person’s voice exactly.

Key disadvantages are:-

  • It can be sensitive to the physical and emotional state of the

individual

  • The voice changes with ageing.
  • It is possible to defraud the sensor recording and playing back

another person’s voice

  • It can be sensitive to background noise


Iris Recognition

The iris, the coloured portion of the eye around the pupil, is also unique to each individual, though its use as a biometric recognition system has up until recently only existed in James Bond films. There are more than 200 separate variables in the design of the iris that can be counted, meaning it is unlikely that two users will be confused. This method was devised by ophthalmologists in the 1980’s who noticed that while the colour of the iris can change over time, the design does not. This technology is new compared with fingerprint technology and identification methods have yet to fully evolve.

Key advantages are: -

  • Each iris is almost as unique as a fingerprint
  • The iris is easily visible and can be photographed.

Key disadvantages are: -

  • The process is considered invasive, because of having to place

the eye close to a special camera

  • Lighting conditions can cause reflections


The Retina

The retina is the back of the eye that images are projected upon. This zone is crossed by blood vessels: you can sometimes see shadows of these when you have an eye test.
The arrangement of these blood vessels is as varied as fingerprints, their relative positions remains unchanged throughout a person’s life, they are not susceptible to cuts or burns and cannot be forged. Although it is considered the most reliable biometric system, it is unpopular because of its invasive nature: a light has to be shone into the eye in order that the retina can be seen by the sensor. As a result this technology will remain more expensive than others due to the lack of mass production.

Signature

Each person has their own style of writing. A template could therefore be made of a user’s signature, and then be used to verify a person’s identity. The main advantage of this type of biometric system is that it is universally acceptable, but people’s signatures often vary, meaning it is difficult to get a very high-scoring match between the template signature and the one presented at the graphics tablet. These are used by some banks for withdrawing money at the counter, but not for time and attendance yet.

Other Techniques

Other systems that are still being developed include ear or lip geometry, the way you walk, body odour, heart beat and many other techniques. It is difficult to predict which of these technologies will be practical partners for time & attendance systems.

[edit] Overview

Many organisations suspect that some employees may be clocking in for their friends. Employees may also be persistently losing their cards or fobs or leaving them at home. It costs time and money to update the employee’s work record in the time and attendance system or to produce a new card. Each organisation must consider whether biometric technology is the most appropriate answer for their problems. There is no one-size-fits-all solution.
Ninety-nine percent of biometric systems are based on fingerprint or hand-geometry biometrics. Public acceptability is likely to increase as many types of organisations from schools to banks continue to find uses for biometric technology.
Despite not being signatories to the Schengen agreement, the UK government has introduced passports that include a computer chip to retain biometric information to help prevent identity theft. The Russian passport authorities have already introduced similar passports in preparedness of any government decision to do so. Eventually employees will get used to biometrics to prove who they are, and will recognise that in a workplace situation it will improve their security and safety.
It will also show clearly and accurately which of their colleagues are at work and pulling their weight, and which are unfairly offloading their workload onto their long-suffering colleagues.



[edit] See also

[edit] External Links

Mitrefinch Ltd - Biometric Time and Attendance and Job Costing Solutions - North America:[1]United Kingdom: [2]