Patent ID: 7415114

Claim:
A method of forming keys in a quantum key distribution (QKD) system, comprising: transmitting encoded qubits, based on single-photon light pulses, from a first encoder/decoder (“Alice”) to a second encoder/decoder (“Bob) each respectively connected to respective Alice and Bob digital computers; from said transmitted encoded qubits, determining initial quantum keys QKA and QKB; determining an initial QKA value of a first function applied to said initial QKA, wherein a value of said first function depends upon values of a specified information unit i of a quantum key (QK); determining an initial QKB value of said first function applied to said initial QKB; and communicating between the Alice and Bob digital computers information about initial keys QKA and QKB so as to enable the formation of a revised QKA by depending a value of an information unit of said revised QKA on a value of said information unit i of said initial QKA, if said initial QKA value equals said initial QKB value.