Frequency-Shift Attack

The Frequency-Shift Attack is a sophisticated strategy where the threat actor (Eve) replaces the receiver's (Bob's) optical pulses with time-shifted ones - in the two-way QKD scheme, aiming to modulate these pulses at the rising edge of the transmitter's (Alice's) phase modulator. This manipulation results in a frequency shift of Alice's signals that correlates with the selected quantum state, enabling Eve to decipher the key by simply analyzing the frequency of the returned signals.

Literature