RFID

Wireless tags used for tracking and access badges; cloneable.

Radio Frequency Identification uses radio waves so a reader can communicate with small tags, commonly embedded in access badges, inventory labels, and asset trackers. In security it often underpins physical entry systems. A significant weakness is that many low-cost tags transmit static identifiers without encryption, making them susceptible to cloning, skimming, and replay attacks from nearby readers. Countermeasures include shielded sleeves, encrypted or challenge-response credentials, and pairing the badge with a second factor for sensitive areas.