NFC is a set of short-range wireless technologies, typically requiring a distance of 10 cm or less. 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 tags contain data and are typically read-only, but may be rewriteable. The tags can securely store personal data such as debit and credit card information, loyalty program data, PINs and networking contacts, among other information.
Like other ‘proximity card’ technologies, NFC employs electromagnetic induction between two loop antennae when NFC devices—for example a ‘smartphone’ and a ‘smart poster’—exchange information, operating within the globally available unlicensed radio frequency ISM band of 13.56 MHz on ISO/IEC 18000-3 air interface at rates ranging from 106 to 424 kbit/s. The NFC Forum defines four types of tags that provide different communication speeds and capabilities in terms of configurability, memory, security, data retention and write endurance. Tags currently offer between 96 and 4,096 bytes of memory.
NFC is inexpensive to deploy but does require some chip-level configuration and administration which can be cumbersome in mass. Currently Apple does not offer full access to their NFC chip in their mobile devices – it is limited to use with ApplePay. Most Google Android powered devices offer full access to the NFC chip to power communications between smartphones and NFC chips for purposes of consumer driven information access.