Near Field Communication (NFC)
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What is NFC and How does it work?
It is a short-distance wireless communication technology. When two NFC enabled devices are very close to each other (around 4 cm), then they can communicate with each other using radio waves.
- Atleast one of the device should be active device like smart phone, tablet, or post terminal.
NFC supports three modes of communications:
- Peer to Peer communication mode
- E.g., when we share information between two smart phones.
- In this mode, both devices are active devices. They can communicate with each other by generating radio waves alternatively. When one device transmits data, the other listens to it and vice-versa.
- Reader/Writer Mode:
- E.g. when we access data from smart phones using NFC tags.
- This mode is similar to RFID. Here the active device like smartphones and tablets reads of writes the data on NFC tag using the principle of electromagnetic induction. A time varying electromagnetic field generates the voltage in this passive tag. This voltage powers up the chip in this NFC tag. Once powered up the tag responds with its own information.
- Card Emulation Mode
- E.g. when smartphones are used for mobile payments.
- Both devices are active device. One device will be a smart phone and the second device is a payment terminal. Here, smartphone acts like a passive smart card and don’t generate their own radio waves. They only respond back with the requested data by the payment termina Operating principle in this mode is similar to reader/writer mode.
Applications
- File sharing
- Contactless payments: NFC is behind the cards that we have over card readers on shops
- Mobile payments
- Pairing different devices
- Information sharing using smart posters and business cards
- Home automation
- NFC tech is present in new age speakers, household appliances, and other electronic devices that we monitor and control through our smartphones.
- g. changing temperature of AC, ambient lighting etc.
- Automatic closing of doors
- Healthcare: NFC is used to monitor patients stats through NFC-enabled wristbands.
- Library systems: Keeping tabs on library books
- Preventing Auto theft
- Personal usage
- Running unmanned toll booths
- Wireless charging
Advantages over other forms of communication
- NFC vs Bluetooth: While Bluetooth provides for higher data rate sharing; But NFC reduces the time required for pairing of devices. In case of NFC the two devices can be set up in less than 0.1 seconds. Once the pairing between devices is done, for communications either Bluetooth or wifi can be used.
- NFC vs RFID: NFC is derived from RFID standards and the working principles are quite similar to RFID. But RFID works on large band of frequencies (LF: 125 kHz or 134 kHz) HF: 13.56 MHz; UHF: 860-960 MHz). But NFC works on a particular frequency bande. 13.56 MHz band. In case of RFID, the reader sends the request to the RFID tag and in response the RFID tag replies back to the reader. So, in case of RFID there is only one way communication. While in case of NFC peer to peer communication is possible.
- NFC vs QR Codes: In case of QR codes, scanning if required to access the information. In case of NFC, just by tapping mobile to NFC tag, information can be easily accessed. Therefore, access time required in case of NFC is less than that of QR code. Further NFC is more secure than the QR code. Because in case of QR code, wrong information may be provided by putting another QR code on top of the 1st QR code, while in case of NFC, if someone puts another NFC tag on top of the first one, then neither of the tags would be accessed. Thus, NFC tech is more secure than the QR code
How secure is this tech?
- Since NFC works at very close distance, it makes it difficult for attackers to record or communication between the devices compared to other wireless technologies.
- The user of the NFC-enabled device determines by the touch gesture which entity the NFC communication should take place with, making it more difficult for the attacker to get connected.
- Peer to Peer communication provides a mechanism to cipher all exchanged data to avoid external interpretation of recorded communication.
When did NFC tech start?
- In 2004, consumer electronics companies, Nokia, Philips, and Sony together formed the NFC forum, which outlined the architecture for NFC technology to create powerful new consumer driven products.