Near field communication

Near field communication (often shortened to NFC) is the name for a standard that uses radio communication technology to send data over short distances. Usually, the distance covered is in the order of four centimeters. The standard is mostly used for micropayment systems. Another common use is to store tickets, such as those used for trains and buses on a re-usable smartcard. Many universities equip their student ID cards so they can be used to pay small amounts, for example a cup of coffee in a cafeteria.

Tickets can also be validated using NFC technology with this machine from the Austrian State Railways. If a NFC capable mobile phone is held to the spot saying "NFC", an SMS message with a ticket will be sent.

Each device is either active or passive; some can assume both roles.

• The devices that communicate need to be very close to each other (or touch each other). This system is often used for ticketing applications
• Bluetooth is sometimes used in addition, to bridge medium distances. This is often used with security tokens for access control. That way, the two devices simply need to be close to each other, in the order of 10-15 cm; touching is no longer required.