Near field communication, or NFC, is a set of short-range wireless technologies, typically requiring a distance of 4 cm or less. NFC operates at 13.56 MHz and at rates ranging from 106 kbit/s to 848 kbit/s. NFC always involves an initiator and a target; the initiator actively generates an RF field that can power a passive target. This enables NFC targets to take very simple form factors such as tags, stickers, key fobs, or cards that do not require batteries. NFC peer-to-peer communication is of course possible, where both devices are powered. According to the NFC Forum, the three main uses of NFC currently are “sharing, pairing, and transaction.” [1] Global companies are interested in NFC’s ability to provide pervasive marketing, simplify processes, and facilitate contactless payment for goods.
NFC tags contain simple data or elaborate instructions that enable them to perform such functions as unlocking doors, paying for goods, launching phone calls or exchanging data between users. The majority of tags for consumer applications are read-only. However, NFC tags can also be read and rewriteable. They can be custom-encoded by their manufacturers or use the specifications provided by the NFC Forum, an industry association charged with promoting the technology and setting key standards. The tags can securely store personal data such as debit and credit card information, loyalty program data, PINs and networking contacts, among other information. The NFC Forum defines four types of tags which provide different communication speeds and capabilities in terms of configurability, memory, security, data retention and write endurance. Tags currently offer between 96 and 512 bytes of memory.