NFC (Near Field Communication)
The Secure Element chip. This is an NFC chip that contains data such as the SEID (Secure Element Identifier) for secure transactions. This chip is commonly found in smartphones and other NFC enabled devices.
Near-field communication (NFC) is a set of communication protocols that enable two electronic devices to establish communication by bringing them within 4 cm (11⁄2 in) of each other.
NFC devices are used in contactless payment systems, similar to those used in credit cards and electronic ticket smart cards and allow mobile payment to replace or supplement these systems. This is sometimes referred to as NFC/CTLS (contactless) or CTLS NFC. NFC is used for social networking, for sharing contacts, photos, videos or files. NFC-enabled devices can act as electronic identity documents and keycards. NFC offers a low-speed connection with simple setup that can be used to bootstrap more capable wireless connections.
Similar ideas in advertising and industrial applications were not generally successful commercially, outpaced by technologies such as barcodes and UHF RFID tags. NFC protocols established a generally supported standard. When one of the connected devices has Internet connectivity, the other can exchange data with online services.
NFC-enabled portable devices can be provided with application software, for example, to read electronic tags or make payments when connected to an NFC-compliant apparatus. Earlier close-range communication used technology that was proprietary to the manufacturer for applications such as stock tickets, access control and payment readers.
Like other “proximity card” technologies, NFC is based on inductive coupling between two so-called antennas present on NFC-enabled devices—for example a smartphone and a printer—communicating in one or both directions, using a frequency of 13.56 MHz in the globally available unlicensed radio frequency ISM band using the ISO/IEC 18000-3 air interface standard at data rates ranging from 106 to 424 Kbit/s.
Every active NFC device can work in one or more of three modes:
NFC card emulation
Enables NFC-enabled devices such as smartphones to act like smart cards, allowing users to perform transactions such as payment or ticketing.
Enables NFC-enabled devices to read information stored on inexpensive NFC tags embedded in labels or smart posters.
Enables two NFC-enabled devices to communicate with each other to exchange information in an ad hoc fashion.
NFC tags are passive data stores which can be read, and under some circumstances written to, by an NFC device. They typically contain data (as of 2015 between 96 and 8,192 bytes) and are read-only in normal use, but may be rewritable. Applications include secure personal data storage (e.g. debit or credit card information, loyalty program data, personal identification numbers (PINs), contacts). NFC tags can be custom-encoded by their manufacturers or use the industry specifications.
The standards were provided by the NFC Forum. The forum was responsible for promoting the technology and setting standards and certifies device compliance. Secure communications are available by applying encryption algorithms as is done for credit cards [5and if they fit the criteria for being considered a personal area network.
NFC standards cover communications protocols and data exchange formats and are based on existing radio-frequency identification (RFID) standards including ISO/IEC 14443 and Felicia. The standards include ISO/IEC 18092] and those defined by the NFC Forum. In addition to the NFC Forum, the GSMA group defined a platform for the deployment of GSMA NFC Standards within mobile handsets. GSMA’s efforts include Trusted Services Manager, Single Wire Protocol, testing/certification and secure element.
A patent licensing program for NFC is under deployment by France Brevets, a patent fund created in 2011. This program was under development by Via Licensing Corporation, an independent subsidiary of Dolby Laboratories, and was terminated in May 2012. A platform-independent free and open source NFC library, libnfc, is available under the GNU Lesser General Public License. Present and anticipated applications include contactless transactions, data exchange and simplified setup of more complex communications such as Wi-Fi
NFC vs. RFID difference?
NFC is a subset of RFID. Like other wireless standards such as Bluetooth and Wi-Fi, RFID uses radio waves to transmit information. RFID stands for Radio Frequency Identification and acts as an umbrella term for all types of contactless communication. Technically, RFID operates at 3 distinct frequency range.
These frequency ranges allow generic RFID devices to be tailored to different se-cases, with each frequency having its own advantages. NFC, as a subset of RFID, operates within the High Frequency (HF) range of the RFID spectrum.
While RFID and NFC are based on the same underlying technology, they differ in a few important ways.
NFC technical specification:
NFC is a set of short-range wireless technologies, typically requiring a separation of 10 cm or less. NFC operates at 13.56 MHz on ISO/IEC 18000-3 air interface and at rates ranging from 106 Kbit/s to 424 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 unpowered tags, stickers, key fobs, or cards. NFC peer-to-peer communication is possible, provided both devices are powered
NFC tags contain data and are typically read-only, but may be writable. They can be custom-encoded by their manufacturers or use NFC Forum specifications. 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 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.
As with proximity card technology, NFC uses inductive coupling between two nearby loop antennas effectively forming an air-core transformer. Because the distances involved are tiny compared to the wavelength of electromagnetic radiation (radio waves) of that frequency (about 22 meters), the interaction is described as near field. Only an alternating magnetic field is involved so that almost no power is actually radiated in the form of radio waves (which are electromagnetic waves, also involving an oscillating electric field); that essentially prevents interference between such devices and any radio communications at the same frequency or with other NFC devices much beyond its intended range. They operate within the globally available and unlicensed radio frequency ISM band of 13.56 MHz Most of the RF energy is concentrated in the ±7 kHz bandwidth allocated for that band, but the emission’s spectral width can be as wide as 1.8 MHz] in order to support high data rates.
Working distance with compact standard antennas and realistic power levels could be up to about 20 cm (but practically speaking, working distances never exceed 10 cm). Note that because the pickup antenna may be quenched by nearby metallic surfaces, the tags may require a minimum separation from such surfaces.
The ISO/IEC 18092 standard supports data rates of 106, 212 or 424 Kbit/s.
The communication takes place between an active “initiator” device and a target device which may either be:
The initiator device provides a carrier field and the target device, acting as a transponder, communicates by modulating the incident field. In this mode, the target device may draw its operating power from the initiator-provided magnetic field.
Both initiator and target device communicate by alternately generating their own fields. A device stops transmitting in order to receive data from the other. This mode requires that both devices include power supplies.