jueves, 23 de mayo de 2013

Near Field Communication

NFC, new ways of communication

NFC is an emerging technology that allows electronic devices to establish communication between them without any kind of wired connection, only by approaching the two devices until they reach contact. This method of communication is known as "tap and go" or "touch and go" and is so named due to the need to bring the two devices to the point where they touch to initiate communication. The maximum distance to establish connection between the two devices is about 10 centimetres.

There are two different modes of communication: the active and the passive mode. The main difference is that in active mode the device creates its own RF field to send the information, whereas in the passive mode the device doesn’t have to create a new RF field because it uses the one created by the other device.

NFC operates at a very short distance; the optimal range between two devices in order to start a connection is from 2 to 4 centimetres. The communication implies two actors. The active device generates a RF field that can be used by the other device. This feature allows having NFC receptors as simple as stickers or tags because they don’t require any battery or power source in order to work.

These small stickers are normally used for reading information such as personal data, bank account’s information, PINs, etc. Nevertheless, the information contained can be rewritten. They have a range memory from 96 bytes to 4 Kbytes.

There are three modes of communication

· Reader / Writer

This mode allows the mobile to read the data stored on NFC or RFID tags and it is normally used to add additional information in posters, or also for identifying products or storing web addresses related to the object to which it is attached. This mode also has the ability to write data in some tags.

· Card Emulation

This mode allows mobile devices to make bank transactions in the same way that credit cards or debit cards. Therefore, this mode is used for identification, payment or access applications with some control.

· Peer-to-Peer

This mode allows mobile devices to interact with each other. Each phone must be equipped with NFC technology. Thus, the communication starts when both terminals approach at a very short distance. All kind of information can be shared between them: business cards, documents, photos or other personal information.