Near Field Communication (NFC) technology is designed to connect two nearby devices quickly, easily, securely, and temporarily. That makes ideal for a wide variety of consumer and business applications, such as:
- Connecting a smartphone to a supermarket payment terminal.
- Unlocking the door to an office or hotel room using a smartphone or fob.
- Automating smart home applications such as turning on certain lights as soon as the user’s smartphone comes into range.
Here’s how NFC works, how it compares to other short-range wireless technologies, and how to implement it successfully.
How NFC Works
NFC uses electromagnetic induction between the coil/loop antennas in each device. There’s no need for a physical connection, such as tapping the devices together, to establish the data connection. They just need to be close enough for induction to occur, which is about 4 centimeters.
NFC supports data transfers at up to 424 kbps. That bandwidth is more than enough for applications such as transferring payment information or validating a ticket at a turnstile.
Like Radio Frequency Identification (RFID) technology, NFC operates at 13.56 MHz. This enables applications such as using NFC to enable a smartphone to open a hotel room door whose lock uses RFID.
NFC has three operating modes:
- Card Emulation Mode, where the NFC device acts as a contactless card to facilitate payments or access secure locations. This mode is widely used in mobile payment systems like Apple Pay, Google Wallet, and Samsung Pay.
- Peer-to-Peer, where two NFC-enabled devices exchange data directly, such as photos, files, or digital business cards. In this mode, NFC establishes the connection, and then a faster technology — such as Bluetooth — handles the data transfer.
- Reader/Writer Mode, where the NFC device reads data from or writes data to an NFC tag.
Like cellular, Wi-Fi, Bluetooth, and other wireless technologies, NFC can be equipped with encryption and other security mechanisms to protect data and user privacy.
Why Bluetooth isn’t Just Another Name for NFC
Bluetooth enables communications between nearby devices, which is why it’s sometimes assumed to be just another name for NFC. But the two technologies are actually different in several ways that affect their use cases:
- NFC uses much less power than Bluetooth. This makes it a good fit for battery-powered Internet of Things (IoT) devices.
- Bluetooth has a range of about 10 meters versus about 4 cm for NFC. The shorter range makes NFC a better fit for payments because there’s less risk of interference from nearby devices and less opportunity for fraudsters to eavesdrop on transactions.
- Bluetooth requires users to manually pair the devices on their initial connection, such as entering a PIN code or choosing the other device from a list. NFC is designed to handle all of those steps without user involvement, making it ideal for one-time use cases such as a tourist paying for a train ticket rather than connecting her new earbuds to her smartphone.
- Bluetooth supports up to 3 Mbps, depending on the version. That makes it a better fit for brief connections that involve larger amounts of data.
What are NFC Tags?
An NFC tag is a small, passive device that contains a microchip and an NFC antenna. These tags can store a small amount of data and can be programmed to perform specific tasks when scanned.
NFC tags can be affixed to or embedded in a wide variety of objects, including stickers, cards, and key fobs, for applications such as:
- Smart Posters: When scanned, NFC tags embedded in posters can provide additional information, such as event details or promotional offers.
- Product Authentication: NFC tags can verify the authenticity of products, such as pharmaceuticals, helping to combat counterfeiting.
- Inventory Tracking: A product’s NFC tag can be scanned at the loading dock, store shelf, or shipping department to track its location and status, and to determine when more need to be ordered.
- Automation: NFC tags can be used to automate tasks on smartphones, such as enabling Wi-Fi, setting alarms, or sending pre-written text messages.
