Due to the compromise of the security of the underlying system or machine stonng the key, exposure of the private key can be a devastating attack on a cryptosystem. Key insulation is an important technique to protect ...Due to the compromise of the security of the underlying system or machine stonng the key, exposure of the private key can be a devastating attack on a cryptosystem. Key insulation is an important technique to protect private keys. To deal with the private （signing） key exposure problem in identity-based signature systems, we propose an identity-based threshold key-insulated signature （IBTKIS） scheme. It strengthens the security and flexibility of existing identity-based key-insulated signature schemes. Our scheme＇ s security is proven in the random oracle model and rests on the hardness of the computational Diffie-Helhnan problem in groups equipped with a pairing. To the best of our knowledge, it is the first IBTKIS scheme up to now.展开更多
Public-key cryptosystems for quantum messages are considered from two aspects:public-key encryption and public-key authentication.Firstly,we propose a general construction of quantum public-key encryption scheme,and t...Public-key cryptosystems for quantum messages are considered from two aspects:public-key encryption and public-key authentication.Firstly,we propose a general construction of quantum public-key encryption scheme,and then construct an informationtheoretic secure instance.Then,we propose a quantum public-key authentication scheme,which can protect the integrity of quantum messages.This scheme can both encrypt and authenticate quantum messages.It is information-theoretic secure with regard to encryption,and the success probability of tampering decreases exponentially with the security parameter with regard to authentication.Compared with classical public-key cryptosystems,one private-key in our schemes corresponds to an exponential number of public-keys,and every quantum public-key used by the sender is an unknown quantum state to the sender.展开更多
The security properties of quantum key distribution(QKD) system are analyzed with the practical light source using decoy state method. The secure key rate with the change of transmission distance is computed under the...The security properties of quantum key distribution(QKD) system are analyzed with the practical light source using decoy state method. The secure key rate with the change of transmission distance is computed under the condition of ideal system, infinite light source system, untrusted light source and passive system. The influence of the fluctuation of transmission rate on the security characteristics of the system is discussed. Our numerical simulation results offer a useful reference for the practical QKD experiment.展开更多
基金Supported by the National Natural Science Foundation of China （No. 60970111, 61133014, 60903189, 60903020）.
文摘Due to the compromise of the security of the underlying system or machine stonng the key, exposure of the private key can be a devastating attack on a cryptosystem. Key insulation is an important technique to protect private keys. To deal with the private （signing） key exposure problem in identity-based signature systems, we propose an identity-based threshold key-insulated signature （IBTKIS） scheme. It strengthens the security and flexibility of existing identity-based key-insulated signature schemes. Our scheme＇ s security is proven in the random oracle model and rests on the hardness of the computational Diffie-Helhnan problem in groups equipped with a pairing. To the best of our knowledge, it is the first IBTKIS scheme up to now.
基金supported by the National Natural Science Foundation of China (Grant No. 61173157)Strategy Pilot Project of Chinese Academy of Sciences (Grant No. Sub-project XD06010702)IIE’s Cryptography Research Project
文摘Public-key cryptosystems for quantum messages are considered from two aspects:public-key encryption and public-key authentication.Firstly,we propose a general construction of quantum public-key encryption scheme,and then construct an informationtheoretic secure instance.Then,we propose a quantum public-key authentication scheme,which can protect the integrity of quantum messages.This scheme can both encrypt and authenticate quantum messages.It is information-theoretic secure with regard to encryption,and the success probability of tampering decreases exponentially with the security parameter with regard to authentication.Compared with classical public-key cryptosystems,one private-key in our schemes corresponds to an exponential number of public-keys,and every quantum public-key used by the sender is an unknown quantum state to the sender.
基金Supported by the National Natural Science Foundation of China under Grant No.61571060Ministry of Science and Technology of China under Grant No.2016YFA0301300
文摘The security properties of quantum key distribution(QKD) system are analyzed with the practical light source using decoy state method. The secure key rate with the change of transmission distance is computed under the condition of ideal system, infinite light source system, untrusted light source and passive system. The influence of the fluctuation of transmission rate on the security characteristics of the system is discussed. Our numerical simulation results offer a useful reference for the practical QKD experiment.
