Quantum key agreement protocol based on GHZ state

Abstract

The invention discloses a quantum key agreement protocol based on GHZ state, comprising the following steps that: step 1, Alice and Bob randomly generate respective classical keys; step 2, Alice prepares the GHZ state and divides all particles into sequences, inserts decoy photons into one of the sequences and then transmits the sequence to Bob; step 3, Bob measures the decoy photons, Alice calculates an error rate, if the error rate is low, a step 4 is executed, otherwise, the step 2 is executed again; step 4, Alice and Bob respectively perform measurement and obtain the measurement result of each other; step 5, Alice executes unitary transformation and obtains a new sequence, and Alice transits the sequence with the inserted decoy photons to Bob; step 6, Bob measures the decoy photons, and Alice calculates the error rate, if the error rate is low, a step 7 is executed, and otherwise, the step 2 is executed again; step 7, Alice calculates a shared key of both sides; step 8, Bob generates the shared key. The quantum key agreement protocol based on GHZ state can resist participant attack, outside attack and Trojan horse attack. The quantum key agreement protocol based on GHZ state is safe in both a noiseless quantum channel and a quantum noisy channel. Moreover, quantum bit efficiency of the quantum key agreement protocol based on GHZ state is higher than the existing protocols.

Description

technical field [0001] The invention belongs to the field of quantum communication, and in particular relates to a quantum key agreement (Quantum key agreement) protocol, in particular to a quantum key agreement agreement based on a GHZ state. Background technique [0002] Quantum cryptography is a new technology for communication and network security, and its security is guaranteed by the basic principles of quantum mechanics. Unlike traditional cryptography, which is mostly computationally secure, quantum cryptography can achieve unconditional security, which has attracted a lot of attention. The quantum key agreement (QKA) protocol is a new important branch of quantum cryptography, which allows participants to negotiate a classical shared secret key through an open quantum channel, and the contribution of each participant is the same, any participant None or a subset of participants can independently determine the shared secret. Using the shared secret key established b...

AI Technical Summary

Problems solved by technology

The disadvantage of this protocol is: since the protocol is a Ping-Pong protocol, that is, the same particle is transmitted back and forth in the quantum channel, the protocol cannot resist the invi

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