Sound-Proximity: 2-Factor Authentication against Relay Attack on Passive Keyless Entry and Start System
Table 1
Components of experimental setup.
Name
Specifications
Explanation
Laptop
CPU Intel i7 2.9 GHz RAM 16 GB running Window 8.1
Represents a car that emits a beacon sound (challenge). Both the ambient noise and a challenge are recorded simultaneously with the key, and the sound-similarity estimation algorithm is applied.
Raspberry Pi
Type B+ RAM 1 GB running Contiki OS
Represents a key that records both the ambient noise and a challenge (beacon sound) simultaneously with the car. Then, audio file is transmitted to the sound-similarity estimator in the car.
Microphone
Frequency response 20 Hz–18 KHz
Used for both the laptop (car) and the Raspberry Pi (key) to record sounds.
Loudspeaker
Frequency response 20 Hz–20 KHz
Used by the laptop (car) to emit a beacon sound (challenge).
Mobile phone
Apple iPhone 6s and SAMSUNG Galaxy Note
Used for a record-and-playback attack. The two mobile phones are connected to one another in speaker mode via a cellular (3G) network.
