NFC

NFC, or near-field communication, is a short-range wireless technology that enables data exchange between two devices at close proximity. Operating at 13.56 MHz, NFC builds on RFID technology and allows communication over a practical distance of a few centimeters, typically up to about 4 cm, though some applications report slightly longer ranges. The technology is defined and standardized by industry groups and international standards bodies, with interoperability supported through the NFC Forum and ISO/IEC specifications.

NFC supports three main modes of operation: reader/writer, card emulation, and peer-to-peer. In reader/writer mode, a device can read information from or write to passive NFC tags. In card emulation mode, a device acts as a contactless card and can be used for payments or access control. In peer-to-peer mode, two devices exchange information directly. Data exchange is commonly performed using the NFC Data Exchange Format (NDEF), and rates typically begin at 106 kbit/s, with higher rates available in some configurations.

Standards and formats underpinning NFC include ISO/IEC 14443 (for contactless cards) and ISO/IEC 18092 (Near Field Communication), with Type 4 tag structures and compatibility with NDEF messaging. In payment applications, NFC often relies on secure elements or host card emulation and tokenization to support contactless payments and other financial services that adhere to EMV and related specifications.

Common applications span contactless payments, transit fares, access control, quick data sharing between devices, and the use of smart posters or tags to convey information. Security considerations emphasize the short range as a natural safeguard, while recognizing risks such as eavesdropping, eavesdropping-resistant designs, encryption, and secure element technologies to protect sensitive data. The technology has seen broad adoption in smartphones, wearables, and embedded devices since its standardization in the early 2000s.