Thursday, 6 March 2014

NFC mechanism.

NFC stands for “Near Field Communication” & as the name implies, it enables short range communication between compatible devices. This requires at least one transmitting device & another to receive the signal. A range of devices can use the NFC standard and can be considered either passive or active, depending on how the device works.

Passive NFC devices include tags & other small transmitters, that can send information to other NFC devices without the need for a power source of their own. However, they don’t really process any information sent from other sources & can’t connect to other passive components. These often take the form of interactive signs on walls or advertisements.

Active devices are able to both send & receive data & can communicate with each other as well as with passive devices. Smartphones are by far the most common implementation of active NFC devices but public transport card readers & touch payment terminals are also good examples of this technology.

NFC came out of RFID. RFID or radio-frequency identification, is the technology used by shipping companies and in superstores to keep track of goods, it uses electromagnetic induction in order to transmit information. NFC is similar technology but standardized for consumer smartphones. NFC standards are defined by a group called the NFC Forum which includes Nokia, Sony and Philips.

How NFC works?
NFC is a means of sending data over radio waves. In that sense it is similar to Wi-Fi or Bluetooth but unlike those protocols (& like RFID) NFC can be used to induce electric currents within passive components as well as just send data. It is faster than Bluetooth, in general. Indeed the two are closely linked, Samsung Beam uses NFC to pair devices, and then Bluetooth to transfer data.

NFC can work with passive devices that don't require their own power supply, such as travel card readers. NFC's data-transmission frequency is 13.56MHz. NFC can transmit data at either 106, 212 or 424 Kbps (kilobits per second).

NFC standard has three modes of operation
(i) The peer-to-peer mode that lets two smartphones swap data.
(ii) A read/write mode in which one active device picks up info from a passive one.
(iii) Card emulation, in which an NFC device such as a smartphone can be used like a contactless credit card.

Uses Of NFC:

NFC technology is used in five basic sectors.

(i) Commerce: NFC devices can be used in contactless payment systems, similar to those currently used in credit cards & electronic ticket smart-cards & allow mobile payment to replace or supplement these systems.
Example: Google Wallet allows consumers to store credit card & store loyalty card information in a virtual wallet & then use an NFC-enabled device at terminals that also accept MasterCard PayPass transactions.
[Google Wallet is an NFC based wireless payment system that allows its users to store debit and credit card information to make payments at PayPass-enabled terminal at checkouts.]

(ii) Bluetooth & Wi-Fi connections: NFC offers a low-speed connection with extremely simple setup & can be used to bootstrap more capable wireless connections.
Example: The Android Beam software uses NFC to complete the steps of enabling, pairing & establishing a Bluetooth connection when doing a file transfer. Nokia, Samsung, BlackBerry & Sony have used NFC technology to pair Bluetooth headsets, media players, and speakers with one tap in its NFC-enabled devices. The same principle can be applied to the configuration of Wi-Fi networks.

(iii) Social Networking: NFC can be used in social networking situations, such as sharing contacts, photos, videos or files & entering multiplayer mobile games. In the field of social networking, NFC is very useful to exchange contacts & other files.

(iv) Identity & access Tokens: The NFC Forum promotes the potential for NFC-enabled devices to act as electronic identity documents & keycards. As NFC has a short range & supports encryption, it may be more suitable than earlier, less private RFID systems.

(v) Smartphone automation & NFC tags: Smartphones equipped with NFC can be paired with NFC Tags or stickers which can be programmed by NFC apps to automate tasks. These programs can allow for a change of phone settings, a text to be created & sent, an app to be launched, or any number of commands to be executed, limited only by the NFC app & other apps on the smartphone.

These applications are perhaps the most practical current uses for NFC since it does not rely on a company or manufacturer but can be utilized immediately by anyone anywhere with an NFC-equipped smartphone & an NFC tag.