The groups of transistors that perform the chip’s logical operations are known as logic gates. By analyzing the pattern of logic gates on the chip, the researchers determined which circuits performed which functions; for example, a string of one-bit memory cells known as flip-flops pointed to the part of the chip responsible for cryptography. The researchers made a map of the logic gates and the connections between them, which allowed them to uncover the chip’s cryptographic algorithm and determine that it was weak. Nohl says that RFID security could be improved by the use of stronger, peer-reviewed algorithms, along with measures to obscure or tamper-proof the circuit itself.
Hear more from MIT at EmTech MIT.