In a broad context, radio transmissions containing some type of identifying information are considered Radio Frequency Identification (RFID). This can be a cab driver using his unit number over the air, or the call sign of a radio station. This chapter discusses the tools, applications, and security of RFID.
RFID is about devices and technology that use radio signals to exchange identifying data. In the usual context, this implies a small tag or label that identifies a specific object. The action receives a radio signal, interprets it, and then returns a number or other identifying information. (e.g., "What are you?" answered with "I am Inventory Item Number 12345").
Alternatively, it can be as complex as a series of cryptographically encoded challenges and responses, which are then interpreted through a database, sent to a global satellite communications system, and ultimately influence a backend payment system.
Some of the current uses of RFID technology include:
Point of Sale (POS)
Automated Vehicle Identification (AVI) systems
Restrict access to buildings or rooms within buildings
Pet ownership identification
Warehouse management and logistics
Product tracking in a supply chain
Raw material tracking/parts movement within factories
Library books check-in/check-out
Railroad car tracking
Luggage tracking at airports