Distance Bounding With IEEE 802.15.4a: Attacks and Countermeasures
Impulse Radio Ultra-Wideband, in particular the recent standard IEEE 802.15.4a, is a primary candidate for implementing distance bounding protocols, thanks to its ability to perform accurate indoor ranging. Distance bounding protocols allow two wireless devices to securely estimate the distance between themselves, with the guarantee that the estimate is an upper-bound on the actual distance. These protocols serve as building blocks in security-sensitive applications such as tracking, physical access control, or localization. The authors investigate the resilience of IEEE 802.15.4a to physical-communication-layer attacks that decrease the distance measured by distance bounding protocols, thus violating their security. They consider two attack types: malicious prover (internal) and distance-decreasing relay (external).