CN104468117A - Quantum dialogue protocol with collective-dephasing noise resisting authentication based on logic Bell states - Google Patents

Abstract

The invention provides a quantum dialogue protocol with collective-dephasing noise resisting authentication based on logic Bell states. Through the protocol, mutual identity authentication and dialogue can be simultaneously achieved securely between two participators on a collective-dephasing noise channel, wherein information transmitted through a classical channel can be intercepted and modified. A secret key used for selecting a sample logic qubit measurement base is shared by the two participators secretly in advance. Bell state measurement, instead of four-qubit joint measurement, is adopted for decoding. The two participators share the initial state of the information logic Bell state by the aid of direct transmission of the auxiliary logic Bell state. In this way, information leakage is avoided. Acting attacks from Eve, man-in-the-middle attacks and modification attacks can all be detected, and besides Trojan attacks can be avoided naturally.

Description

Phase noise certification quantum session protocol moves back in the anti-collective of logic-based Bell state

Technical field

The present invention relates to field of quantum security communication.Phase noise certification quantum session protocol moves back in the anti-collective that the present invention designs a kind of logic-based Bell state, reaches the object simultaneously realizing mutual identity authentication and dialogue in the noisy communication channel of collective's dephasign position between two participants safely.

Background technology

Between two participants, the direct transmission of secret information is carried out in order to realize throughput subsignal, Long and Liu [1] proposed first Quantum Secure Direct Communication (Quantum Secure DirectCommunication, QSDC) agreement (be called as subsequently state encode two step agreements) in 2002.This agreement has invented this thought of quantal data Bulk transport.From then on, many good QSDC agreements are fabricated out [2-11].

Between two participants, carry out the two-way communication of secret information to realize throughput subsignal, Nguyen [12] and Zhang etc. [13-14] are the independent concept proposing quantum dialogue (QuantumDialogue, QD) in 2004.After this, many QD agreements are suggested [15-24] according to different quantum techniques.Unfortunately, always there is the security risk being referred to as information leakage found in 2008 by [25-26] such as Gao in them.In fact, to result from the classics that Tan with Cai [27] pointed out in 2008 relevant for the information leakage problem of QD.Subsequently, the QD agreement how designed without information leakage causes rapidly the interest of researchers.Like this, many good anti-information leakage QD agreements are devised [28-37].

But above-mentioned all QD agreements [12-24,28-37] are just operated on following basis: can not be ravesdropping and revise by the information of classical transmission.Once this hypothesis is false, their face external assailant at once and play the part of the serious security risk that the attacks such as attacks, man-in-the-middle attack and amendment attack cause.Like this, a kind of special QD agreement being referred to as certification quantum dialogue (Authenticated Quantum Dialogue, AQD) is put forward to make up this defect by [39] such as Naseri [38] and Shen.But point out in 2013 as [40] such as Lin, the agreement [39] of Shen etc. is subject to man-in-the-middle attack and threatens.The agreement [38] of Naseri is no exception under this kind of attack.Subsequently, in order to improve the fail safe of AQD, Lin etc. [41] propose an AQD agreement based on Bell state, and wherein two participants can realize mutual identity authentication and dialogue safely simultaneously.In the agreement [41] of Lin etc., two kinds of secret keys are shared in confidence by two participants, and wherein the first secret key is for the preparation of initial Bell state.In this case, two participants enjoy initial Bell state in advance.But in anti-information leakage QD field, the initial state of quantum state is not enjoyed by two participants usually in advance.Another shortcoming of the agreement [41] of Lin etc. is that it is only operated in ideal communication channel.It is important to point out, anti-information leakage QD agreement [28-37] before is also operated in ideal communication channel only.In fact, harmful being coupled between photon with actual environment inevitably exists.Therefore, the impact of interchannel noise should be considered.Point out as document [42-43], transmit in time window faster if photon to change than noise at one, interchannel noise can be regarded as collective's noise.The first collective's noise is that phase noise moves back in collective, total keeps the horizontal polarization state of photon | and 0> is constant and by the perpendicular polarization state of photon | and 1> changes into | 1> [44].Another kind of noise is collective's rotational noise, always will | 0> and | 1> is separately converted to coS θ | 0>+sin θ | 1> and-sin θ | 0>+coS θ | 1> [46].Here, corresponding time dependent noise parameter with θ.As the means of a kind of effective opposing collective noise, not affected by noise has been commonly used to design antinoise quantum cryptographic protocols without eliminating coherence (Decoherence-Free, DF) state [42-54].Such as, the robust QD agreement of document [51] and document [53] utilizes the product state of two quantum bit DF states and two quantum bit DF states as quantum resource respectively, and the robust QD agreement of document [54] utilizes four quantum bit DF states as quantum resource.

Based on above analysis, phase noise AQD agreement is moved back by the anti-collective that the present invention utilizes logic Bell state (a kind of four quantum bit DF states) to propose a logic-based Bell state as quantum resource, wherein can be ravesdropping and revise by the information of classical transmission.Agreement proposed by the invention can realize mutual identity authentication and dialogue safely in the noisy communication channel of collective's dephasign position between two participants simultaneously.With the protocol class of document [41] seemingly, a kind of secret key for selecting sample logic quantum bit to measure base is shared in confidence by two participants in advance.Bell state is measured but not four quantum bit combined measurements are used for decoding.With the QD protocol class of document [54] seemingly, two participants are by means of directly transmitting the initial state that auxiliary logic Bell state shares infologic Bell state.Like this, information leakage problem is avoided.Play the part of attack, man-in-the-middle attack and amendment from Eve are attacked and can be detected, and Trojan attack is avoided natively.

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Summary of the invention

Phase noise AQD agreement is moved back by the anti-collective that the object of the invention is to design a kind of logic-based Bell state, reaches the object simultaneously realizing mutual identity authentication and dialogue in the noisy communication channel of collective's dephasign position between two participants safely.

A phase noise AQD agreement is moved back by the anti-collective of logic-based Bell state, comprises following seven processes altogether:

S1) Alice prepares 2N infologic Bell state { (A ₁, B ₁), (A ₂, B ₂) ..., (A _2n-1, B _2n-1), (A _2n, B _2n) ..., (A _2N-1, B _2N-1), (A _2N, B _2N) (n=1,2 ..., N), wherein every two adjacent infologic Bell state (A _2n-1, B _2n-1) and (A _2n, B _2n) be produced and be in identical quantum state and (be in four quantum states at random one of), with first protocol class of document [54] seemingly.The logic quantum bit A that Alice chooses respectively with odd index and even index carrys out composition sequence S _oAand S _eA.Namely,

S _oA={ A ₁, A ₃..., A _2n-1..., A _2N-1and S _eA={ A ₂, A ₄..., A _2n..., A _2N.Alice also does same thing to logic quantum bit B.Correspondingly, S is had _oB={ B ₁, B ₃..., B _2n-1..., B _2N-1and S _eB={ B ₂, B ₄..., B _2n..., B _2N.Then, in order to safety detection and mutual identity authentication, Alice prepares the sample logic Bell state (quantity of sample logic Bell state equals the length of K) of sufficient amount, and these sample logic Bell state is divided into two subsequences be made up of logic quantum bit A and B respectively.Then, the subsequence radom insertion S that will be made up of sample logic quantum bit A of Alice _eAto form S ' _eA.Similarly, Alice is to sample logic quantum bit B and S _eBdo same thing to form S ' _eB.Then, Alice keeps S _oA, S ' _eAand S _oBmotionless, and by a quantum channel by S ' _eBsend Bob to.Obviously, S ' _eBbe sent out in the mode of Bulk transport [1].

S2) inform that Alice receives S ' at Bob _eBafter, Alice detects S ' _eBtransmission security and the identity of certification Bob.Alice tells BobS ' by a classical channel _eBthe position of middle sample logic quantum bit.S ' is measured according to K, Bob _eBin sample logic quantum bit to obtain measurement result then, Bob is by the measurement result of classical channel by him send to Alice.S ' is measured according to K, Alice _eAin sample logic quantum bit to obtain measurement result because Alice prepares sample logic Bell state in person, according to with she can judge S ' simultaneously _eBthe existence of listener-in and the identity of Bob between transmission period.If Alice finds wrong, her interrupt communication; Otherwise, she also with the mode throughput subchannel of Bulk transport [1] by S ' _eAsend Bob to.

S3) inform that Alice receives S ' at Bob _eAafter, Alice tells BobS ' _eAthe position of middle sample logic quantum bit.Then, Bob abandons S ' _eAwith S ' _eBin sample logic quantum bit.Correspondingly, S ' _eAwith S ' _eBtransformed back into S respectively _eAand S _eB.Then, Bob is from S _eAand S _eBchoose logic quantum bit A respectively _2nand B _2n, and they are saved as 2n infologic Bell state again.Then, in order to know (A _2n, B _2n) quantum state, Bob applies two Bell state to the 1st and the 3rd quantum bit and the 2nd and the 4th quantum bit respectively and measures.Due to every two adjacent infologic Bell state (A _2n-1, B _2n-1) and (A _2n, B _2n) to be prepared in step S1 by Alice and to be in identical quantum state, Bob can from (A _2n, B _2n) directly know (A _2n-1, B _2n-1) quantum state.

S4) Alice also with the mode throughput subchannel of Bulk transport [1] by S _oBsend Bob to.Then, Bob is from S _qBselect N/4 logic quantum bit as sample logic quantum bit and tell their position of Alice by classical channel.S is measured according to K, Alice _oAin corresponding sample logic quantum bit to obtain measurement result then, Alice is by the measurement result of classical channel by her send to Bob.S is measured according to K, Bob _oBin sample logic quantum bit to obtain measurement result then, because Bob knows (A in step S3 _2n-1, B _2n-1) quantum state, according to with he can judge S simultaneously _oBthe existence of listener-in and the identity of Alice between transmission period.If Bob finds wrong, his interrupt communication; Otherwise communication continues.

S5) Alice and Bob abandons S respectively in order _oAand S _oBin sample logic quantum bit.Conveniently, remaining S _oAand S _oBuse S ' respectively _oA=A ' ₁, A ' ₂..., A ' _3N/4and S ' _oB=B ' ₁, B ' ₂..., B ' _3N/4represent.Then, in order to encode, Alice is to A ' _d(d=1,2 ..., 3N/4) and apply logic operation at the tenth of the twelve Earthly Branches like this, S ' _oAbe converted into $S_{\mathrm{OA}}^{\′\′}=\{{\mathrm{\Ω}}_{i_1{j}_1}{A}_1^{\′},{\mathrm{\Ω}}_{i_2{j}_2}{A}_2^{\′},...,{\mathrm{\Ω}}_{i_{3N/4}{j}_{3N/4}}{A}_{3N/4}^{\′}\}.$ Then, Alice also with the mode throughput subchannel of Bulk transport [1] by S " _oAsend Bob to.

S6) S is being received " _oAafter, in order to encode, Bob couple apply logic operation at the tenth of the twelve Earthly Branches like this, S " _oAbe converted into $S_{\mathrm{OA}}^{\′\′\′}=\{{\mathrm{\Ω}}_{t_1{l}_1}{\mathrm{\Ω}}_{i_1{j}_1}{A}_1^{\′},{\mathrm{\Ω}}_{t_2{l}_2}{\mathrm{\Ω}}_{i_2{j}_2}{A}_2^{\′},...,{\mathrm{\Ω}}_{t_{3N/4}{l}_{3N/4}}{\mathrm{\Ω}}_{i_{3N/4}{j}_{3N/4}}{A}_{3N/4}^{\′}\}.$ Then, Bob is from S " ' _oAwith S ' _oBchoose respectively with B ' _dwith form d (d ∈ 1,2 ..., 3N/4}) and group.Then, in order to know quantum state, Bob applies two Bell state to the 1st and the 3rd quantum bit and the 2nd and the 4th quantum bit respectively and measures.According to the logic operation at the tenth of the twelve Earthly Branches of himself right with him measurement result, Bob can read (i _d, j _d), because he know (A ' _d, B ' _d) quantum state.Here, the classical bit decoded is represented as m ' _a|| h (m _a) ', be m ' wherein _athe m decoded _a, h (m _ah (the m that) ' be decodes _a).Then, with the protocol class of document [41] seemingly, Bob calculates m ' _acryptographic Hash (be referred to as h (m ' _a)) and by h (m ' _a) and h (m _a) ' compare.If they are identical, m ' _areal m is thought by Bob _aand communication continues; Otherwise communication is terminated.

S7) Bob is right by him by classical channel

measurement result send to Alice.Similarly, according to the logic operation at the tenth of the twelve Earthly Branches of herself alice can know (t _d, l _d) (d ∈ 1,2 ..., 3N/4}) because herself preparation (A ' _d, B ' _d).Here, the classical bit decoded is represented as m ' _b|| h (m _b) ', be m ' wherein _bthe m decoded _b, h (m _bh (the m that) ' be decodes _b).Then, with the protocol class of document [41] seemingly, Alice calculates m ' _bcryptographic Hash (be referred to as h (m ' _b)) and by h (m ' _b) and h (m _b) ' compare.If they are identical, m ' _breal m is thought by Alice _b; Otherwise communication is terminated.

Phase noise AQD agreement is moved back by the anti-collective that the present invention proposes a kind of logic-based Bell state.The agreement that the present invention proposes can realize mutual identity authentication and dialogue safely in the noisy communication channel of collective's dephasign position between two participants simultaneously.Here, can be ravesdropping and revise by the information of classical transmission.A kind of secret key for selecting sample logic quantum bit to measure base is shared in confidence by two participants in advance.Bell state is measured but not four quantum bit combined measurements are used for decoding.Two participants share the initial state of infologic Bell state to avoid information leakage problem by means of directly transmitting auxiliary logic Bell state.Play the part of attack, man-in-the-middle attack and amendment from Eve are attacked and can be detected, and Trojan attack is avoided natively.

Embodiment

Below in conjunction with embodiment, technical scheme of the present invention is described further.

1, there is the logic Bell state of anti-collective's dephasign position noise jamming consistency and ultra dense coding thereof

Four logic Bell state that collective moves back under phase noise can be represented as [48]

$\begin{array}{c}|{\mathrm{\Φ}}_{\mathrm{dp}}^{+}{\⟩}_{1234}=\frac{1}{\sqrt{2}}{\left(\right|0_{\mathrm{dp}}\⟩|0_{\mathrm{dp}}\⟩+|1_{\mathrm{dp}}\⟩\left|1_{\mathrm{dp}}\right)}_{1234}=\frac{1}{\sqrt{2}}{\left(\right|01\⟩|01\⟩+|10\⟩|10\⟩)}_{1234}\\ =\frac{1}{\sqrt{2}}{\left(\right|{+}_{\mathrm{dp}}\⟩|{+}_{\mathrm{dp}}\⟩+|{-}_{\mathrm{dp}}\⟩|{-}_{\mathrm{dp}}\⟩)}_{1234}=\frac{1}{\sqrt{2}}{\left(\right|00\⟩|11\⟩+|11\⟩|00\⟩)}_{1324}\\ =\frac{1}{\sqrt{2}}{\left(\right|{\mathrm{\φ}}^{+}\⟩|{\mathrm{\φ}}^{+}\⟩-|{\mathrm{\φ}}^{-}\⟩|{\mathrm{\φ}}^{-}\⟩)}_{1324},\end{array}$

$\begin{array}{c}|{\mathrm{\Φ}}_{\mathrm{dp}}^{-}{\⟩}_{1234}=\frac{1}{\sqrt{2}}{\left(\right|0_{\mathrm{dp}}\⟩|0_{\mathrm{dp}}\⟩-|1_{\mathrm{dp}}\⟩\left|1_{\mathrm{dp}}\right)}_{1234}=\frac{1}{\sqrt{2}}{\left(\right|01\⟩|01\⟩-|10\⟩|10\⟩)}_{1234}\\ =\frac{1}{\sqrt{2}}{\left(\right|{+}_{\mathrm{dp}}\⟩|{-}_{\mathrm{dp}}\⟩+|{-}_{\mathrm{dp}}\⟩|{+}_{\mathrm{dp}}\⟩)}_{1234}=\frac{1}{\sqrt{2}}{\left(\right|00\⟩|11\⟩-|11\⟩|00\⟩)}_{1324}\\ =\frac{1}{\sqrt{2}}{\left(\right|{\mathrm{\φ}}^{-}\⟩|{\mathrm{\φ}}^{+}\⟩-|{\mathrm{\φ}}^{+}\⟩|{\mathrm{\φ}}^{-}\⟩)}_{1324},\end{array}$

$|{\mathrm{\Ψ}}_{\mathrm{dp}}^{+}{\⟩}_{1234}=\frac{1}{\sqrt{2}}{\left(\right|0_{\mathrm{dp}}\⟩|1_{\mathrm{dp}}\⟩+|1_{\mathrm{dp}}\⟩|0_{\mathrm{dp}}\⟩)}_{1234}=\frac{1}{\sqrt{2}}{\left(\right|01\⟩|10\⟩+|10\⟩|01\⟩)}_{1234}$

$\begin{array}{c}=\frac{1}{\sqrt{2}}{\left(\right|{+}_{\mathrm{dp}}\⟩|{+}_{\mathrm{dp}}\⟩-|d_p\⟩|{-}_{\mathrm{dp}}\⟩)}_{1234}=\frac{1}{\sqrt{2}}{\left(\right|01\⟩|10\⟩+|10\⟩|01\⟩)}_{1324}\\ =\frac{1}{\sqrt{2}}{\left(\right|{\mathrm{\ψ}}^{+}\⟩|{\mathrm{\ψ}}^{+}\⟩-|{\mathrm{\ψ}}^{-}\⟩|{\mathrm{\ψ}}^{-}\⟩)}_{1324},\end{array}$

$\begin{array}{c}|{\mathrm{\Ψ}}_{\mathrm{dp}}^{-}{\⟩}_{1234}=\frac{1}{\sqrt{2}}{\left(\right|0_{\mathrm{dp}}\⟩|1_{\mathrm{dp}}\⟩-|1_{\mathrm{dp}}\⟩\left|0_{\mathrm{dp}}\right)}_{1234}=\frac{1}{\sqrt{2}}{\left(\right|01\⟩|10\⟩-|10\⟩|01\⟩)}_{1234}\\ =\frac{1}{\sqrt{2}}{\left(\right|{+}_{\mathrm{dp}}\⟩|{-}_{\mathrm{dp}}\⟩+|{-}_{\mathrm{dp}}\⟩|{+}_{\mathrm{dp}}\⟩)}_{1234}=\frac{1}{\sqrt{2}}{\left(\right|01\⟩|10\⟩-|10\⟩|01\⟩)}_{1324}\\ =\frac{1}{\sqrt{2}}{\left(\right|{\mathrm{\ψ}}^{-}\⟩|{\mathrm{\ψ}}^{+}\⟩-|{\mathrm{\ψ}}^{+}\⟩|{\mathrm{\ψ}}^{-}\⟩)}_{1324},\end{array}---\left(1\right)$

Wherein $|{\mathrm{\φ}}^{\±}\⟩=\frac{1}{\sqrt{2}}\left(\right|00\⟩\±|11\⟩)$ With $|{\mathrm{\ψ}}^{\±}\⟩=\frac{1}{\sqrt{2}}\left(\right|01\⟩\±|10\⟩)$ Four original Bell state.Here, | 0 _dp>=|01> and | 1 _dp>=|10> is two logic quantum bits [44] to collective's dephasign position noise immunity, their superposition state $|{\±}_{\mathrm{dp}}\⟩=\frac{1}{\sqrt{2}}\left(\right|0_{\mathrm{dp}}\⟩\±|1_{\mathrm{dp}}\⟩)=\frac{1}{\sqrt{2}}\left(\right|01\⟩\±|10\⟩)$ Also not by this noise effect [46].Correspondingly, under this noise, two logics measurement bases just produce thereupon, i.e. Z _dp=| 0 _dp>, | 1 _dp>} and X _dp=|+ _dp>, |- _dp>}.Easily know from formula (1), as long as two Bell state measurements are applied separately at the 1st and the 3rd quantum bit and the 2nd and the 4th quantum bit, above-mentioned four logic Bell state can be distinguished to each other.[48] and, one in four logics operation at the tenth of the twelve Earthly Branches that these four logic Bell state define by formula (2) to each other transforms mutually.[48-49]

${\mathrm{\Ω}}_I=I_1\⊗I_2,{\mathrm{\Ω}}_z=U_{z1}\⊗I_2,{\mathrm{\Ω}}_x=U_{x1}\⊗U_{x2},{\mathrm{\Ω}}_y=U_{y1}\⊗U_{x2}.---\left(2\right)$

Here, I=|0><0|+|1>LEs sT.LTssT.LT1|, U _x=| 1><0|+|0>LEssT. LTssT.LT1|, U _y=| 0><1|-|1>LEssT. LTssT.LT0 and U _z=| 0><0|-|1>LEssT. LTssT.LT1|.

Suppose that Alice and Bob decides through consultation that four logics operation at the tenth of the twelve Earthly Branches that formula (2) describes represents classical bit with following form in advance:

Ω _I→Ω ₀₀，Ω _z→Ω ₀₁，Ω _x→Ω ₁₀，Ω _y→Ω ₁₁。(3) here, each numeric suffix represents a classical dibit.

2, AQD agreement

Suppose that Alice has 3N/2 classical bit { (i ₁, j ₁) (i ₂, j ₂) ... (i _d, j _d) ... (i _3N/4, j _3N/4) (be expressed as m _a|| h (m _a)), wherein m _aher secret, h (m _a) be the cryptographic Hash of her secret; Bob has 3N/2 classical bit { (t ₁, l ₁) (t ₂, l ₂) ... (t _d, l _d) ... (t _3N/4, l _3N/4)(be expressed as m _b|| h (m _b)), wherein m _bhis secret, h (m _b) be the cryptographic Hash of his secret.Here, " || " represents connection, and i _d, j _d, t _d, l _d∈ 0,1}, wherein d ∈ 1,2 ..., 3N/4}.With the protocol class of document [41] seemingly, a kind of secret key K for selecting sample logic quantum bit to measure base is assumed to be further to be shared in confidence in advance between Alice and Bob.Here, K ∈ { 0,1} ^n/4.That is, if the p of K (p=1,2 ..., N/4) and bit is 0, Z _dpbase is used to measurement p sample logic quantum bit; Otherwise, X _dpbase is used to measure it.Agreement hypothesis of the present invention can be ravesdropping and revise by the information of classical transmission, comprises following seven processes altogether:

S1) Alice prepares 2N infologic Bell state

{ (A ₁, B ₁), (A ₂, B ₂) ..., (A _2n-1, B _2n-1), (A _2n, B _2n) ..., (A _2N-1, B _2N-1), (A _2N, B _2N) (n=1,2 ..., N), wherein every two adjacent infologic Bell state (A _2n-1, B _2n-1) and (A _2n, B _2n) be produced and be in identical quantum state and (be in four quantum states at random one of), with first protocol class of document [54] seemingly.The logic quantum bit A that Alice chooses respectively with odd index and even index carrys out composition sequence S _oAand S _eA.Namely, S _oA={ A ₁, A ₃..., A _2n-1..., A _2N-1and S _eA={ A ₂, A ₄..., A _2n..., A _2N.Alice also does same thing to logic quantum bit B.Correspondingly, S is had _oB={ B ₁, B ₃..., B _2n-1..., B _2N-1and S _eB={ B ₂, B ₄..., B _2n..., B _2N.Then, in order to safety detection and mutual identity authentication, Alice prepares the sample logic Bell state (quantity of sample logic Bell state equals the length of K) of sufficient amount, and these sample logic Bell state is divided into two subsequences be made up of logic quantum bit A and B respectively.Then, the subsequence radom insertion S that will be made up of sample logic quantum bit A of Alice _eAto form S ' _eA.Similarly, Alice is to sample logic quantum bit B and S _eBdo same thing to form S ' _eB.Then, Alice keeps S _oA, S ' _eAand S _oBmotionless, and by a quantum channel by S ' _eBsend Bob to.Obviously, S ' _eBbe sent out in the mode of Bulk transport [1].

S2) inform that Alice receives S ' at Bob _eBafter, Alice detects S ' _eBtransmission security and the identity of certification Bob.Alice tells BobS ' by a classical channel _eBthe position of middle sample logic quantum bit.S ' is measured according to K, Bob _eBin sample logic quantum bit to obtain measurement result then, Bob is by the measurement result of classical channel by him send to Alice.S ' is measured according to K, Alice _eAin sample logic quantum bit to obtain measurement result because Alice prepares sample logic Bell state in person, according to with she can judge S ' simultaneously _eBthe existence of listener-in and the identity of Bob between transmission period.If Alice finds wrong, her interrupt communication; Otherwise, she also with the mode throughput subchannel of Bulk transport [1] by S ' _eAsend Bob to.

S3) inform that Alice receives S ' at Bob _eAafter, Alice tells BobS ' _eAthe position of middle sample logic quantum bit.Then, Bob abandons S ' _eAwith S ' _eBin sample logic quantum bit.Correspondingly, S ' _eAwith S ' _eBtransformed back into S respectively _eAand S _eB.Then, Bob is from S _eAand S _eBchoose logic quantum bit A respectively _2nand B _2n, and they are saved as 2n infologic Bell state again.Then, in order to know (A _2n, B _2n) quantum state, Bob applies two Bell state to the 1st and the 3rd quantum bit and the 2nd and the 4th quantum bit respectively and measures.Due to every two adjacent infologic Bell state (A _2n-1, B _2n-1) and (A _2n, B _2n) to be prepared in step S1 by Alice and to be in identical quantum state, Bob can from (A _2n, B _2n) directly know (A _2n-1, B _2n-1) quantum state.

S4) Alice also with the mode throughput subchannel of Bulk transport [1] by S _oBsend Bob to.Then, Bob is from S _oBselect N/4 logic quantum bit as sample logic quantum bit and tell their position of Alice by classical channel.S is measured according to K, Alice _oAin corresponding sample logic quantum bit to obtain measurement result then, Alice is by the measurement result of classical channel by her send to Bob.S is measured according to K, Bob _oBin sample logic quantum bit to obtain measurement result then, owing to knowing (A in step S3 _2n-1, B _2n-1) quantum state, according to with he Bob can judge S simultaneously _oBthe existence of listener-in and the identity of Alice between transmission period.If Bob finds wrong, his interrupt communication; Otherwise communication continues.

S5) Alice and Bob abandons S respectively in order _oAand S _oBin sample logic quantum bit.Conveniently, remaining S _oAand S _oBuse S ' respectively _oA=A ' ₁, A ' ₂..., A ' _3N/4and S ' _oB=B ' ₁, B ' ₂..., B ' _3N/4represent.Then, in order to encode, Alice couple apply logic operation at the tenth of the twelve Earthly Branches like this, S ' _oAbe converted into $S_{\mathrm{OA}}^{\&prime;\&prime;}=\{{\mathrm{\&Omega;}}_{i_1{j}_1}{A}_1^{\&prime;},{\mathrm{\&Omega;}}_{i_2{j}_2}{A}_2^{\&prime;},...,{\mathrm{\&Omega;}}_{i_{3N/4}{j}_{3N/4}}{A}_{3N/4}^{\&prime;}\}.$ Then, Alice also with the mode throughput subchannel of Bulk transport [1] by S " _oAsend Bob to.

S6) S is being received " _oAafter, in order to encode, Bob couple apply logic operation at the tenth of the twelve Earthly Branches like this, S " _oAbe converted into $S_{\mathrm{OA}}^{\&prime;\&prime;\&prime;}=\{{\mathrm{\&Omega;}}_{t_1{l}_1}{\mathrm{\&Omega;}}_{i_1{j}_1}{A}_1^{\&prime;},{\mathrm{\&Omega;}}_{t_2{l}_2}{\mathrm{\&Omega;}}_{i_2{j}_2}{A}_2^{\&prime;},...,{\mathrm{\&Omega;}}_{t_{3N/4}{l}_{3N/4}}{\mathrm{\&Omega;}}_{i_{3N/4}{j}_{3N/4}}{A}_{3N/4}^{\&prime;}\}.$ Then, Bob is from S " ' _oAwith S ' _oBchoose respectively with B ' _dwith form d (d ∈ 1,2 ..., 3N/4}) and group.Then, in order to know quantum state, Bob applies two Bell state to the 1st and the 3rd quantum bit and the 2nd and the 4th quantum bit respectively and measures.According to the logic operation at the tenth of the twelve Earthly Branches of himself right with him measurement result, Bob can read (i _d, j _d), because he know (A ' _d, B ' _d) quantum state.Here, the classical bit decoded is represented as m ' _a|| h (m _a) ', be m ' wherein _athe m decoded _a, h (m _ah (the m that) ' be decodes _a).Then, with the protocol class of document [41] seemingly, Bob calculates m ' _acryptographic Hash (be referred to as h (m ' _a)) and by h (m ' _a) and h (m _a) ' compare.If they are identical, m ' _areal m is thought by Bob _aand communication continues; Otherwise communication is terminated.

S7) Bob is right by him by classical channel measurement result send to Alice.Similarly, according to the logic operation at the tenth of the twelve Earthly Branches of herself alice can know (t _d, l _d) (d ∈ 1,2 ..., 3N/4}) because herself preparation (A ' _d, B ' _d).Here, the classical bit decoded is represented as m ' _b|| h (m _b) ', be m ' wherein _bthe m decoded _b, h (m _bh (the m that) ' be decodes _b).Then, with the protocol class of document [41] seemingly, Alice calculates m ' _bcryptographic Hash (be referred to as h (m ' _b)) and by h (m ' _b) and h (m _b) ' compare.If they are identical, m ' _breal m is thought by Alice _b; Otherwise communication is terminated.

3, safety analysis

(1) attack is played the part of

With the protocol class of document [41] seemingly, what always have two kinds of situations here plays the part of attack.

The first situation is: in order to obtain the classical bit of Alice, Eve plays the part of Bob and Alice and communicates.But because Eve does not know the secret key K for selecting sample logic quantum bit to measure base, she is to S ' _eBthe random measurement of middle sample logic quantum bit can not produce really therefore, when Alice passes through assessment in step S2 with mistake between relation with the identity of certification Bob time, Eve can be detected.

Second case is: in order to obtain the classical bit of Bob, Eve plays the part of Alice and Bob and communicates.The S ' that Eve preparation is false _eB, S ' _eA, S _oBand S _oA, and by the S ' of vacation _eB, S ' _eAand S _oBbob is sent to respectively in step S1, S2 and S4.Then, false S is measured according to K, Bob _oBin sample logic quantum bit and obtain one false owing to not knowing K, the S of Eve random measurement vacation _oAin corresponding sample logic quantum bit and obtain one false obviously, false with vacation between relation be inharmonic.Therefore, when Bob is in step S4 false by assessment with vacation between relation with the identity of certification Alice time, Eve can be detected.

(2) man-in-the-middle attack

In order to obtain the classical bit of Alice and Bob, Eve independently communicates to apply man-in-the-middle attack by setting up two with them.[41] S ' that Eve preparation is false _eB, S ' _eA, S _oBand S _oA, and replace with them all real logic quantum bits transmitted between Alice and Bob.As above analyzed, Eve is detected in the mutual certification of Alice and Bob, because she can not prepare out real initial state and measurement result.

(3) amendment is attacked

The object that the amendment of Eve is attacked is to make participant obtain the classical bit of mistake.[41] with the protocol class of document [41] seemingly, the amendment always having two kinds of situations is here attacked.

The first situation is: the S that to send Bob at amendment Alice in step S5 to " _oAafter, Eve sends amended version to Bob.Due to S " _oAcontain h (m _a), the amendment of Eve is attacked and is detected by Bob in step S6 is to the verification process of the classical bit of Alice, even if only have S " _oAa logic quantum bit be modified.

Second case is: send to Alice at amendment Bob in step S7 measurement result (be represented as R _msg) after, Eve sends amended version to Alice.Due to R _msgcontain h (m _b), the amendment of Eve is attacked and is detected by Alice in step S7 is to the verification process of the classical bit of Bob.

Can reach a conclusion, hashing operation makes the amendment of Eve attack to detect.

(4) Trojan attack

Always having two kinds of Trojan attack, is invisible photon eavesdropping [56] and delay photon Trojan attack [57] respectively.Because all logic quantum bits are the one-way transmission from Alice to Bob only, the agreement that the present invention proposes is natively to Trojan attack immunity.

Embodiment:

1, AQD protocol application citing

Suppose (i ₁, j ₁) and (t ₁, l ₁) be (0,1) and (1,0) respectively.And, suppose (A ' ₁, B ' ₁) be produced and be in Ω is applied respectively at Alice and Bob ₀₁and Ω ₁₀after encoding, (A ' ₁, B ' ₁) be converted into then, Bob can easily read (i ₁, j ₁) be (0,1).By classical channel, he is right at Bob measurement result send to Alice after, Alice can easily infer (t ₁, l ₁) be (1,0).Decoding m ' _a|| h (m _a) ' after, Bob calculating h (m ' _a) and by h (m ' _a) and h (m _a) ' compare is with the m of certification Alice _a.Similarly, m ' is being decoded _b|| h (m _b) ' after, Alice calculating h (m ' _b) and by h (m ' _b) and h (m _b) ' compare is with the m of certification Bob _b.

2, discuss

Information leakage problem refers to that any other people does not need to carry out any active attack only from declaring publicly just energy Extraction parts classical information.Due to every two adjacent infologic Bell state (A _2n-1, B _2n-1) and (A _2n, B _2n) be in identical quantum state, at Alice by S ' by Alice in step S1 preparation _eAwith S ' _eBafter sending Bob to, Bob can from (A _2n, B _2n) directly know (A _2n-1, B _2n-1) initial state.Therefore, Alice there is no need to announce (A to Bob _2n-1, B _2n-1) initial state.Like this, Eve does not have approach to know (A _2n-1, B _2n-1) initial state.In this case, for Eve, measurement result contain the logic operative combination at the tenth of the twelve Earthly Branches of 16 kinds of Alice and Bob.According to the information theory [55] of Shannon, this comprises bit information, just in time equal Alice and Bob by coding classical bit number.Therefore, information is not had to be leaked out.Obviously, (A _2n, B _2n) role that plays the part of auxiliary logic Bell state helps to overcome information leakage problem, with the protocol class of document [54] seemingly.

3, sum up

Phase noise AQD agreement is moved back by the anti-collective that the present invention utilizes logic Bell state to propose a logic-based Bell state as quantum resource, and wherein a kind of secret key for selecting sample logic quantum bit to measure base is shared in confidence by two participants in advance.With QD agreement [12-24 before, 28-39,41,51,53-54] compare, the outstanding advantages of agreement proposed by the invention is: when supposing can be ravesdropping by the information of classical transmission and revise, it can realize mutual identity authentication and dialogue safely in the noisy communication channel of collective's dephasign position between two participants simultaneously.Other of agreement proposed by the invention are characterized as:

(1) measure about quantum, Bell state is measured but not four quantum bit combined measurements are used to decoding;

(2) about information leakage problem, the method directly transmitting auxiliary logic Bell state is used to avoid it;

(3) about the active attack of Eve, play the part of attack, man-in-the-middle attack and amendment and attack and can be detected, and Trojan attack is avoided natively.

Claims (1)

1. a phase noise certification quantum session protocol moves back in the anti-collective of logic-based Bell state, can realize mutual identity authentication and dialogue safely in the noisy communication channel of collective's dephasign position between two participants simultaneously; The information of classical transmission is utilized to be ravesdropping and to revise; A kind of secret key K for selecting sample logic quantum bit to measure base is shared in advance in confidence between two participants; Employing Bell state measures but not four quantum bit combined measurements are used for decoding; Between two participants, the initial state of infologic Bell state is shared to avoid information leakage problem by means of directly transmitting auxiliary logic Bell state; Can detect that play the part of attack, man-in-the-middle attack and amendment from Eve are attacked, and avoid Trojan attack natively; Comprise following seven processes altogether:

S1) Alice prepares 2N infologic Bell state

{ (A ₁, B ₁), (A ₂, B ₂) ..., (A _2n-1, B _2n-1), (A _2n, B _2n) ..., (A _2N-1, B _2N-1), (A _2N, B _2N) (n=1,2 ..., N), wherein every two adjacent infologic Bell state (A _2n-1, B _2n-1) and (A _2n, B _2n) be produced and be in four quantum states at random one of identical quantum state; The logic quantum bit A that Alice chooses respectively with odd index and even index carrys out composition sequence S _oAand S _eA, namely, S _oA={ A ₁, A ₃..., A _2n-1..., A _2N-1and S _eA={ A ₂, A ₄..., A _2n..., A _2N; Alice also does same thing to logic quantum bit B, correspondingly, has

S _oB={ B ₁, B ₃..., B _2n-1..., B _2N-1and S _eB={ B ₂, B ₄..., B _2n..., B _2N; Then, in order to safety detection and mutual identity authentication, Alice prepares the sample logic Bell state (quantity of sample logic Bell state equals the length of secret key K) of sufficient amount, and these sample logic Bell state is divided into two subsequences be made up of logic quantum bit A and B respectively; Then, the subsequence radom insertion S that will be made up of sample logic quantum bit A of Alice _eAto form S ' _eA; Similarly, Alice is to sample logic quantum bit B and S _eBdo same thing to form S ' _eB; Then, Alice keeps S _oA, S ' _eAand S _oBmotionless, and pass through a quantum channel in the mode of Bulk transport by S ' _eBsend Bob to;

S2) inform that Alice receives S ' at Bob _eBafter, Alice detects S ' _eBtransmission security and the identity of certification Bob; Alice tells BobS ' by a classical channel _eBthe position of middle sample logic quantum bit; S ' is measured according to K, Bob _eBin sample logic quantum bit to obtain measurement result then, Bob is by the measurement result of classical channel by him send to Alice; S ' is measured according to K, Alice _eAin sample logic quantum bit to obtain measurement result because Alice prepares sample logic Bell state in person, according to with she can judge S ' simultaneously _eBthe existence of listener-in and the identity of Bob between transmission period; If Alice finds wrong, her interrupt communication, otherwise, she also with the mode throughput subchannel of Bulk transport by S ' _eAsend Bob to;

S3) inform that Alice receives S ' at Bob _eAafter, Alice tells BobS ' _eAthe position of middle sample logic quantum bit; Then, Bob abandons S ' _eAwith S ' _eBin sample logic quantum bit; Correspondingly, S ' _eAwith S ' _eBtransformed back into S respectively _eAand S _eB; Then, Bob is from S _eAand S _eBchoose logic quantum bit A respectively _2nand B _2n, and they are saved as 2n infologic Bell state again; Then, in order to know (A _2n, B _2n) quantum state, Bob applies two Bell state to the 1st and the 3rd quantum bit and the 2nd and the 4th quantum bit respectively and measures; Due to every two adjacent infologic Bell state (A _2n-1, B _2n-1) and (A _2n, B _2n) to be prepared in step S1 by Alice and to be in identical quantum state, Bob can from (A _2n, B _2n) directly know (A _2n-1, B _2n-1) quantum state;

S4) Alice also with the mode throughput subchannel of Bulk transport by S _oBsend Bob to; Then, Bob is from S _oBselect N/4 logic quantum bit as sample logic quantum bit and tell their position of Alice by classical channel; S is measured according to K, Alice _oAin corresponding sample logic quantum bit to obtain measurement result then, Alice is by the measurement result of classical channel by her send to Bob; S is measured according to K, Bob _oBin sample logic quantum bit to obtain measurement result then, because Bob knows (A in step S3 _2n-1, B _2n-1) quantum state, according to with he can judge S simultaneously _oBthe existence of listener-in and the identity of Alice between transmission period; If Bob finds wrong, his interrupt communication, otherwise communication continues;

S5) Alice and Bob abandons S respectively in order _oAand S _oBin sample logic quantum bit; Remaining S _oAand S _oBuse S ' respectively _oA=A ' ₁, A ' ₂..., A ' _3N/4and S ' _oB=B ' ₁, B ' ₂..., B ' _3N/4represent; Then, in order to encode, Alice is to A ' _d(d=1,2 ..., 3N/4) and apply logic operation at the tenth of the twelve Earthly Branches like this, S ' _oAbe converted into $S_{\mathrm{OA}}^{\&prime;\&prime;}=\{{\mathrm{\&Omega;}}_{i_1{j}_1}{A}_1^{\&prime;},{\mathrm{\&Omega;}}_{i_2{j}_2}{A}_2^{\&prime;},\&CenterDot;\&CenterDot;\&CenterDot;,{\mathrm{\&Omega;}}_{i_{3N/4}{j}_{3N/4}}{A}_{3N/4}^{\&prime;}\};$ Then, Alice also with the mode throughput subchannel of Bulk transport by S " _oAsend Bob to;

S6) S is being received " _oAafter, in order to encode, Bob couple apply logic operation at the tenth of the twelve Earthly Branches like this, S " _oAbe converted into $S_{\mathrm{OA}}^{\&prime;\&prime;\&prime;}=\{{\mathrm{\&Omega;}}_{t_1{l}_1}{\mathrm{\&Omega;}}_{i_1{j}_1}{A}_1^{\&prime;},{\mathrm{\&Omega;}}_{t_2{l}_2}{\mathrm{\&Omega;}}_{i_2{j}_2}{A}_2^{\&prime;},\&CenterDot;\&CenterDot;\&CenterDot;,{\mathrm{\&Omega;}}_{t_{3N/4}{l}_{3N/4}}{\mathrm{\&Omega;}}_{i_{3N/4}{j}_{3N/4}}{A}_{3N/4}^{\&prime;}\};$ Then, Bob is from S " ' _oAwith S " _oBchoose respectively with B ' _dwith form d (d ∈ 1,2 ..., 3N/4}) and group; Then, in order to know quantum state, Bob applies two Bell state to the 1st and the 3rd quantum bit and the 2nd and the 4th quantum bit respectively and measures; According to the logic operation at the tenth of the twelve Earthly Branches of himself right with him measurement result, Bob can read (i _d, j _d), because he know (A ' _d, B ' _d) quantum state; Here, the classical bit decoded is represented as m ' _a|| h (m _a) ', be m ' wherein _athe m decoded _a, h (m _ah (the m that) ' be decodes _a); Then, Bob calculates m ' _acryptographic Hash (be referred to as h (m ' _a)) and by h (m ' _a) and h (m _a) ' compare; If they are identical, m ' _areal m is thought by Bob _aand communication continues, otherwise communication is terminated;

S7) Bob is right by him by classical channel

$\{({\mathrm{\&Omega;}}_{t_1{l}_1}{\mathrm{\&Omega;}}_{i_1{j}_1}{A}_1^{\&prime;},B_1^{\&prime;}),({\mathrm{\&Omega;}}_{t_2{l}_2}{\mathrm{\&Omega;}}_{i_2{j}_2}{A}_2^{\&prime;},B_2^{\&prime;}),\&CenterDot;\&CenterDot;\&CenterDot;,({\mathrm{\&Omega;}}_{t_{3N/4}{l}_{3N/4}}{\mathrm{\&Omega;}}_{i_{3N/4}{j}_{3N/4}}{A}_{3N/4}^{\&prime;},B_{3N/4}^{\&prime;})\}$ Measurement result send to Alice; Similarly, according to the logic operation at the tenth of the twelve Earthly Branches of herself alice can know (t _d, l _d) (d ∈ 1,2 ..., 3N/4}) because herself preparation (A ' _d, B ' _d); Here, the classical bit decoded is represented as m ' _b|| h (m _b) ', be m ' wherein _bthe m decoded _b, h (m _bh (the m that) ' be decodes _b); Then, Alice calculates m ' _bcryptographic Hash (be referred to as h (m ' _b)) and by h (m ' _b) and h (m _b) ' compare; If they are identical, m ' _breal m is thought by Alice _botherwise, communication is terminated.