Research On Multiparty Quantum Privacy Comparison

At present,the field of quantum secure computation is getting more and more attention,and as an important branch of quantum secure computation,quantum privacy comparison has also been deeply studied.At present,in the quantum privacy equality relation comparison protocols,most of them can only compare the equality relation of numbers,but cannot compare the equality relation of text.There are some problems in the quantum privacy size relation comparison protocols,such as high resource consumption and low computational efficiency.In view of this,in this thesis,a quantum privacy text equality relation comparison protocol based on d-dimension entangled states and a multi-party quantum privacy size relation comparison protocol based on single photon are proposed.The main research work and innovation points of this thesis are as follows:1.At present,the quantum privacy equality relation comparison protocols are only limited to the comparison of digital equality relation,in response to this question,this thesis proposes three quantum privacy text equality comparison protocols based on d-dimension entangled states.The three protocols first use the Hash function to compress the text information to generate the message digest,then,they encode the message digest into the quantum entangled states,finally,they obtain the comparison result through the inner product or quantum circuit.None of the three protocols uses unitary operation and quantum entanglement exchange technology,which improves the computational efficiency.The three protocols can not only compare the digital equality relation,but also compare the text equality relation,which has better practicability.The first two protocols are a comparison of two private texts,they have the same method of preparing particles.The difference between them is that the first protocol obtains the final comparison result by calculating the inner product,while the second protocol obtains the final comparison result by the quantum circuit diagram.The third protocol is a comparison of multiple private texts,which was obtained with the help of a semi-honest third party by improving the first protocol.2.At present,the quantum privacy size relation comparison protocols consume more resources and has low channel transmission efficiency,in response to this question,this thesis proposes two quantum privacy size relation comparison protocols based on two-dimensional single particles.The two protocols first encode secret integers into the relative phase of the quantum states by unitary operation,which reduces the consumption of quantum resources.Secondly,they transmit two-dimensional single particles in the quantum channel,which improves the transmission efficiency of the channel.Both protocols compare the size relationships of multiple private integers,they are the same in particle preparation,unitary operations,quantum measurement techniques,and so on.their difference is that the first protocol has two semi-honest third parties,the second protocol requires only a semi-honest third party,but requires additional quantum key distribution technology.Although the execution steps of the two protocols are described in detail,only the second protocol includes example verification,security analysis,comparative analysis and simulation experiments.