how to install an access control system (2)

How Does Biometric Access Control System Work?

A lot of science and technology are behind biometric access control and its functionality. The good news is that there’s a straightforward way of explaining things.

Essentially, biometric access control systems record biological data from human beings. They have scanners equipped with them, which collects all of this data. For example, there’s a fingerprint scanner that analyses one of your fingerprints and keeps them in a data file. You then choose who you want to access whatever’s behind the access control system and register their fingerprints.

Now, when you go to open the door, you scan your finger. The system analyses the print and sees if it matches one in the database. If it does, then the access control opens up and lets you in. If there’s no match, then access is denied.

Of course, fingerprints are just one of many examples of biometric access control. However, they’re the most common form of biometrics as it’s easy and convenient to scan a print.

Retina scanning is also used, and this involves scanning the retinas in your eyes. Facial recognition has also started becoming more mainstream – largely thanks to the iPhone X, introducing it to the consumer market in 2018.

Biometric access control is one of the most popular types of security systems on the market. For a good reason: it combines security and convenience in a way that no other access control system can.

Access control refers to managing an access point, such as a door, turnstile, elevator, etc., to only allow entry to authorised users. While access control systems can be used for virtually any access point that uses an electronic lock mechanism, doors are the most common applications for access control.

Biometrics is a method of establishing a person’s identity based on chemical, behavioural, or physical attributes and is relevant in large-scale identity management across a wide range of applications. In addition, this technology can be implemented to regulate access among computer networks, financial transactions, or transportation systems. 

The primary purpose of biometrics in these applications is to determine or verify someone’s identity to prevent unauthorised people from accessing protected resources. 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 access control 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 preset group of attributes in its database, and then performs an action based on the accuracy of the comparison. Various characteristics can be used for biometric comparisons, such as fingerprints, irises, hand geometries, voice patterns, or DNA information. 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, feature comparison and matching unit, and a database. 

Why Are Biometrics Used In Security Systems?

how does biometric access control system work

Traditional access systems have a critical vulnerability: objects and data can be shared or stolen, allowing someone other than the intended user to access the facility if they get a hold of them.

This may or may not be a big deal depending on the level of security that is required.

For example, many coffee shops use a keypad on the bathroom door with the passcode (usually just four digits) printed on the receipt so that visitors can enter, use the restroom, and leave without ordering anything.

Whether this is good customer service or not is beside the point. In this case, the thing that the lock is protecting (a public bathroom) doesn't strictly require level security, so a simple keypad works just fine.

However, such a security system is unfit for anything that requires more serious protection. The problem with passcodes is that, because they are just information, they can be easily shared and distributed among an infinite number of people — even if those people aren't authorised.

Physical access tokens (such as keys, fobs, and ID cards) share a similar vulnerability: they can be easily lost or stolen, allowing whoever has access to the token to have access to the facility — regardless of whether the person accessing it is authorised.

Biometrics, however, don’t have this vulnerability. Because your unique biometric code is always with you, it isn't effortless for anyone other than you to access it.

This is why, while not all biometrics are equal in terms of security, even some of the least secure biometric systems are still more secure than traditional security systems.

What Are The Benefits Of Biometric Access Control?

In general, access control is a valuable security measure. It adds an extra layer of protection that helps control who’s allowed where. But, biometric access control takes things to a whole new level of security.

Standard access control – using keypads and passwords – is that codes can be guessed, and keycards can be lost or stolen.

Also, after frequent use, the numbers on a keypad can appear slightly worn or faded, giving away which numbers make up the code. So, there’s a possibility – although slim – that someone without access can get hold of the code and gain access.

With biometric scanning, this is significantly harder. The only way someone can gain access is to possess a replica of the biological data stored in the system.

You can’t mimic biological data, nor can you take a lucky guess – you’d need someone in the system to be there to get through the access control.

Consequently, biometric access control is far more secure and much harder for someone to break into.

What Can Industries Benefit?

This type of access control has many uses across industries. With that in mind, here are some industries where we believe this technology will be most beneficial:

Public Sector

Government is full of different sections and different people moving around all the time who have additional clearances. What’s more, there’s so much private information in various government buildings. So, to keep things as secure as possible, they could benefit from biometric access control. It can close off structures and stop random people from bursting into government buildings and seeing private information.


The healthcare industry is also packed full of private and confidential information. Again, biometric scanning can be convenient here. It’s often used in hospitals to restrict access to data servers or filing rooms. But, it can also be used to gain access to more confined areas of hospitals – like wings with contagious patients.

General Businesses

This type of access control is also helpful across the general business world. It can be used to protect office buildings – while doubling up as a new way for workers to clock in every morning.

Only your staff can have access to your office, and this prevents unwanted visitors. It can also help shut off private areas, like filing and documentation rooms.

Law Enforcement

Police stations, detention centres, and any other institutions can significantly benefit from biometric access control. A crucial aspect of law enforcement is ensuring the public’s safety. Access control makes sure only select people are allowed in and out of police stations, prisons, detention centres, etc.

It can prevent instances where someone tries to break into a prison to help a prisoner escape – or worse.

As you can see, biometric access control can be used in many different ways. Hopefully, this guide has taught you more about how this technology works and why it’s useful. If you’re looking for a way to enhance your security measures, then this might just be it.

What Are The Different Types Of Biometrics For Access Control?

finger print scan for enter security system with copyspace.

There is four biometrics that is most commonly used for access control:

Palm Vein

Palm vein is a relatively new biometric that works by using infrared light to map the unique vein pattern of the palm. Unlike other biometrics, this pattern is internal to the body, which gives it several unique advantages that make it ideal for access control applications.


  • Best-in-Class Security

Palm vein is arguably the most secure biometric due to how difficult it would be to reverse engineer. Since the biometric pattern is never exposed to the world, it would be complicated for a hacker to build a replica that could be used to spoof the scanner.

Additionally, built-in liveness tests ensure that even if a person could somehow gain access to your palm-vein pattern and create a perfect replica of it, they still wouldn't be able to fool a scanner since actual blood flow is required.

  • Accuracy

Due to the large surface area being captured (the entire palm as opposed to just a fingerprint, for example), palm-vein captures more data points than any other biometric, making it the most accurate biometric on the market.

As such, the palm vein has the lowest False Acceptance Rate (FAR) and False Rejection Rate (FRR) of any biometric.

  • Privacy-by-Design

Palm vein records an internal rather than an external biometric. So unlike facial recognition (which can be captured from a distance without consent), palm veins can’t be caught without a user’s direct interaction with the scanner.

This is why palm vein is uniquely privacy-by-design.

This makes it the more trustworthy choice for users while also making it easier for companies that use it to comply with privacy regulations around the world (such as the GDPR).


  • Potentially reduced accuracy in cold weather

Although this hasn't been practically demonstrated yet in real-world scenarios, extreme cold weather could theoretically reduce scan effectiveness due to cold temperatures restricting blood flow.


When most people think of "biometrics," fingerprint is probably the first thing that comes to mind.

The fingerprint is an old, time-tested biometric. They used fingerprints to authenticate government documents, and they used fingerprints to sign written contracts.

Today, it is used for a large variety of different applications, from identifying suspects at the scene of a crime and conducting background checks to authenticating payments and unlocking mobile devices.


  • Relatively cheap

While price can vary significantly depending on the type of scanner, the fingerprint is generally a very cost-efficient technology. This makes it particularly suitable for mass production, hence its popularity as the go-to biometric in virtually all modern smartphones.

  • Well-known

Fingerprint's popularity as a biometric means that most people are already familiar with it, reducing the need to educate or train people on using it.


  • Susceptible to wear, damage, and change over time

Fingerprints, more so than any other biometric, are vulnerable to wear and damage. Cuts, abrasions, and scars can alter fingerprints significantly enough that fingerprint scanners are no longer able to correctly identify a person who was previously enrolled in the database.

  • Less Sanitary

Of all the biometrics mentioned here, the fingerprint is the only one that requires physical contact with the device. This makes it less suitable for applications where top-notch hygiene is essential, such as restaurants, food manufacturing facilities, and hospitals.

  • Susceptible to being collected and replicated by third parties

Since we leave fingerprints on everything we touch, they are vulnerable to being collected by a third party. Once collected, they can be forged in several ways, such as via 3D printing. This makes less-advanced scanners (that don't have built-in liveness tests) vulnerable to spoofing.

Iris Scan

The unique, highly detailed pattern of the iris makes it a natural choice for biometrics.

Iris scanners use infrared light and high-resolution cameras to create a detailed map of the iris, then convert this information into a template that becomes a person’s biometric ID.


  • Stable

A person's iris patterns remain identical throughout their lifespan, making them a highly durable option.

  • Accurate

Because of the rich level of detail in the retina, scanners can capture many data points, making it a highly accurate biometric. This accuracy is further increased in scanners that scan both eyes.


  • It can be captured from a distance

Modern iris scanners can capture a person’s iris biometrics from over 40 yards away, creating privacy risks similar to facial recognition (albeit less extreme).

Facial Recognition

Face recognition has gained a lot of popularity recently. In airports, for example, airline companies are using this biometric to quickly and conveniently identify travellers, reducing lines and allowing them to board more quickly.

However, this has created controversy because of the privacy concerns this technology poses. Unlike other biometrics, facial recognition can be captured from a distance, making it possible to be caught without consent.


  • Convenience

Facial recognition is probably the easiest-to-use biometric since the person doesn't need to do anything to be identified. Recent smartphone models, for example, allow users to unlock their phone just by looking at the screen automatically.


  • Privacy Risks

Since it can be captured from a distance, facial recognition opens up the possibility of being caught without consent, creating potential privacy and legal risks.

This isn’t a problem when used on personal devices such as phones since the biometric data stays on the device. However, when used in public to automatically identify people, facial recognition creates significant privacy risks.

  • Less Accurate

Facial recognition has a higher False Acceptance Rate (FAR) and False Rejection Rate (FRR) than any other biometric. This is because it 1). FR measures fewer data points than other biometrics, and 2). Changes in appearance (such as facial hair, glasses, makeup, etc.) make it more likely to return a false negative.

Pros And Cons Of Biometrics-based Access Control

Here are just a few of the benefits of using biometrics to safeguard access at work:

  • Increase productivity by eliminating system inaccuracies
  • Enhance employee accountability
  • Track excessive overtime
  • Provide top-notch integration capacity
  • Enable multi-factor authentication with voice and face recognition
  • Multimodal authentication with multiple data enrollments

For the most part, the advantages of biometrics in access control systems widely surpass the assumed vulnerabilities. Almost none of the alternative access control options are so versatile, universal, and well-performing.

However, some privacy concerns come with the increased use of biometrics in access control. For one, many people aren't sure how much personal information they're generally willing to disclose or how their private data is used, and biometrics adds another layer to the data being collected and shared. Some are worried that collecting sensitive data like fingerprints, voices, and facial scans will allow that data to be used maliciously in the future.

Another issue regarding privacy is that in the case of a data breach, biometrics can't be changed the way a password can be: Our fingerprints, voices, and iris patterns are permanent.

On the more tangible side, like any new AI technology, these devices aren't always accurate, leading to unauthorised people being allowed into a facility. Some devices can also take longer than traditional access control to let someone in, which can be a problem if many employees are showing up simultaneously for the workday.

Biometric access control features are permanent and measurable, thus making the access control systems that use them super-applicable over space and time. While we are getting used to having our faces and voices measured, scientists are already working on expanding the biometrics potential to additional human modalities, such as EEG and ECG... It is a matter of a heartbeat.

Biometric devices have some advantages but should be used with caution. If you're considering using biometric measures with your access control system, carefully consider how it will impact your business and if it's the right decision for your business before you take the plunge. For many, though, mobile access control—combined with biometrics or as a standalone system—are a great option. With Kisi, you can get the best of both in a way most people are comfortable with: Using Kisi's cloud-based access control to unlock facility doors with Kisi's mobile app, which people use fingerprint or face recognition to access on their phone.

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