Nortech Control Blog

NFC Access Control: What Is It And How Does It Work?

Written by Elliot Blackler | Apr 24, 2024 12:00:00 PM

NFC-enabled solutions are quickly emerging as a universal standard in access control, due to its ability to operate on low frequency, proximity distances and provide selective access to the building.

To help you navigate the world of NFC access control solutions, we have created this quick guide on everything you need to know to choose the right solution for your needs.

In this Nortech guide, you'll learn: 

  • What is NFC technology and how does it differ between active and passive
  • How NFC applies to access control and smartphone technology
  • The benefits & drawbacks of NFC access control

What Is NFC Technology?

Before we jump into all the different access control solutions, let’s take a look at what this technology is all about and how it works.

NFC or Near Field Communication is a wireless technology that enables short-range communication between compatible devices. NFC requires at a minimum one transmitting device and another to receive the signal. NFC devices operate on the frequency of 13.56 MHz, similar to some of the high-frequency RFID solutions.

NFC technology implements an alternating magnetic field, meaning that no power is emitted in the form of radio waves. This prevents any interference from occurring between similar devices or any radio communications operating at the same frequency.

The NFC-enabled solutions are usually comprised of an initiator (a reader) and a target (tag, card, sticker or a key fob). NFC tags contain data and tend to be read-only. These tags can securely hold personal data, with memory ranging between 96 and 8,192 bytes.

 

NFC Technology: Active vs. Passive

NFC solutions are usually categorised into active and passive categories.

Active NFC

When initiator and target are in an active mode, they can both send and receive data by using an alternate signal transmission. Both devices have a power supply, meaning that the initiator doesn't have to send power to the target for the latter to perform its' task.

All active NFC devices can work in one or more of the following operating modes:

  • Card emulation – enables devices such as smartphones to act as a smart card, allowing users to use it to enter the building or other secured access point.
  • Reader/writer – enables devices to read data stored on tags embedded in access cards or key fobs.
  • Peer-to-peer – enables NFC devices to communicate with each other to exchange data. In this mode, an NFC device can act as both a reader and a tag. This feature is unique to the NFC devices, making this technology a great and flexible solution for companies.

Passive NFC

With passive NFC, the initiator sends a radio frequency power to the target to power it up. After that, the target modulates this power and sends it back to the initiator. In comparison to an active mode, target in the passive mode restructures the amplitude of the original signal to send it back to the initiator.

 

What is NFC-enabled Access Control?

NFC technology considerably simplifies access control and offers a flexible, cost-efficient solution. NFC technology in almost all applications always stays the same, allowing information to be transmitted safely and securely at a short distance.

In most applications, NFC technology implements one card or fob and one reader. The card/fob is programmed with the tag data, which carries the identifying information that will enable a linked access panel to authorise or deny access to the building. However, NFC technology has much more to offer, going beyond simple authentication.

NFC devices can also record the access information, exact access time, how long the access has been granted and many other security metrics and data. This information can then be utilised not only by security professionals but also by HR and managers looking to monitor their company's workflow and attendance.

NFC & Smartphones

Smartphones have become an inseparable part of our daily lives, and this trend is also reflected in access control. More and more access control solutions are integrating smartphones into their systems. This is especially popular with NFC-enabled solutions.

Some of the latest NFC access control systems can even be managed through the apps installed on smartphones, which can then be used as a tag for the NFC reader. So, when the smartphone is tapped over the NFC reader, it activates the communication channel, enabling the data transaction, authenticating the user and granting or denying access to the building.

 

 

Benefits of NFC Access Control

  • Improved user experience. With NFC-enabled devices, organisations can forget about complex passwords, especially in large buildings with high visitor flow.
  • Fast, integrated approach. Smartphones are revolutionising access control industry by offering a fully integrated solution – perfect for large enterprises. With NFC-enabled smartphones, users can use their phones as a key to the building. users are more likely to lose or misplace their credentials, but their phones are always on them making it a more convenient solution.
  • Most NFC devices are compatible with existing RFID systems and are therefore easy to integrate into existing solutions for extra security.
  • Time & Attendance. Organisations can also record real-time information about their employees working hours and attendance. This data is collected every time an employee accesses monitored points within the building. 

Drawbacks of NFC Technology

  • Operating Range. NFC technology only works in short distances (up to 20cm). So, it might not be the best option for applications where it’s not always possible to be in the close proximity to the reader.
  • NFC-enabled access control isn’t entirely risk free, especially solutions that incorporate mobile devices as part of the overall system, as smartphones can be hacked into. In addition to that, simple NFC is vulnerable to eavesdropping, as it doesn’t have any sort of encryption and authentication, therefore, it doesn’t necessarily guarantee a secure communication.
  • Data transfer. NFC offers a relatively low data transfer compared to other technologies – between 106 and 424 Kbps.
  • Compared to other technologies, such as RFID, NFC can be quite costly. So, if you are on a budget, it might be best to consider RFID-enabled devices as they aren’t as complicated as NFC, and have cheaper hardware and setup costs.
  • Power consumption. Whilst NFC doesn’t use as much power as Bluetooth-enabled devices, it still consumer more than RFID-enabled devices. If power consumption is one of your key concerns, then RFID technology might be a better solution for you.