We analyse the security of a quantum secure direct communication （QSDC） protocol and find that an eavesdropper can utilize a special property of GHZ states to elicit all or part of the transmitted secrets without be...We analyse the security of a quantum secure direct communication （QSDC） protocol and find that an eavesdropper can utilize a special property of GHZ states to elicit all or part of the transmitted secrets without being detected. The particular attack strategy is presented in detail. We give an improved version of this protocol so that it can resist this attack.展开更多
The security of the quantum secure direct communication （QSDC） protocol with cluster state is analysed. It is shown that the secret would be partially leaked out when an eavesdropper performs forcible measurements o...The security of the quantum secure direct communication （QSDC） protocol with cluster state is analysed. It is shown that the secret would be partially leaked out when an eavesdropper performs forcible measurements on the transmitted particles. With the help of the result in minimum error discrimination, an upper bound （i.e. 40%） of this leakage is obtained. Moreover, the particular measurements which makes the leakage reach this bound are given.展开更多
基金Supported by the National High-Tech Research and Development Programme of China under Grant No 2006AA01Z419, the Major Research Plan of the National Natural Science Foundation of China under Grant No 90604023, the National Laboratory for Modern Communications Science Foundation of China under Grant No 9140Cl101010601, and the Natural Science Foundation of Beijing under Grant No 4072020.
文摘We analyse the security of a quantum secure direct communication （QSDC） protocol and find that an eavesdropper can utilize a special property of GHZ states to elicit all or part of the transmitted secrets without being detected. The particular attack strategy is presented in detail. We give an improved version of this protocol so that it can resist this attack.
基金Supported by the National High Technology Research and Development Programme of China under Grant No 2006AA01Z4191 the Major Research Plan of the National Natural Science Foundation of China under Grant No 90604023, the National Laboratory for Modern Communications Science Foundation of China under Grant No 9140C1101010601, the Natural Science Foundation of Beijing under Grant No 4072020, and the Open Foundation of State Key Laboratory of Integrated Services Network, Xidian University.
文摘The security of the quantum secure direct communication （QSDC） protocol with cluster state is analysed. It is shown that the secret would be partially leaked out when an eavesdropper performs forcible measurements on the transmitted particles. With the help of the result in minimum error discrimination, an upper bound （i.e. 40%） of this leakage is obtained. Moreover, the particular measurements which makes the leakage reach this bound are given.
