Two signature systems based on smart cards and fingerprint features are proposed. In one signature system, the cryptographic key is stored in the smart card and is only accessible when the signer＇s extracted fingerpr...Two signature systems based on smart cards and fingerprint features are proposed. In one signature system, the cryptographic key is stored in the smart card and is only accessible when the signer＇s extracted fingerprint features match his stored template. To resist being tampered on public channel, the user＇s message and the signed message are encrypted by the signer＇s public key and the user＇s public key, respectively. In the other signature system, the keys are generated by combining the signer＇s fingerprint features, check bits, and a rememberable key, and there are no matching process and keys stored on the smart card. Additionally, there is generally more than one public key in this system, that is, there exist some pseudo public keys except a real one.展开更多
Watermarking is an effective approach to the copyright protection of digital media such as audio, image, and video. By inspiration from cryptography and considering the immensity of the set of all possible wavelets, i...Watermarking is an effective approach to the copyright protection of digital media such as audio, image, and video. By inspiration from cryptography and considering the immensity of the set of all possible wavelets, it is presented that in wavelet domain watermarking, the associated wavelet can be considered as the private key for encrypting the watermark so as to enhance the security of the embedded mark. This idea is partly supported by the fact that from computational complexity viewpoint, it is very time-consuming to search over the immense set of all candidate wavelets for the right one if no a priori knowledge is known about it. To verify our proposal, the standard image 'Lena' is first watermarked in a specific wavelet domain, the watermark recovery experiments are then conducted in the wavelet domain for a set of wavelets with the one used for mark embedded in it,separately. It follows from the experimental results that the mark can be recovered only in the right wavelet domain, which justifies the suggestion.展开更多
Quantum key distribution(QKD)is a secure communication method for sharing symmetric cryptographic keys based on the principles of quantum physics.Its integration into the fiber-optic network infrastructure is importan...Quantum key distribution(QKD)is a secure communication method for sharing symmetric cryptographic keys based on the principles of quantum physics.Its integration into the fiber-optic network infrastructure is important for ensuring privacy in optical communications.Multi-core fibers(MCFs),the likely building blocks of future high-capacity optical networks,offer new opportunities for such integration.Here,we experimentally demonstrate,for the first time,the coexistence of discrete-variable QKD and high-throughput classical communication in the C-band over a fielddeployed MCF with industry standard cladding diameter of 125μm.Specifically,we demonstrate successful secure-key establishment in one core of a 25.2-km uncoupled-core MCF,while simultaneously loading the remaining three cores with full C-band counter-propagating classical traffic at an aggregate net rate of 110.8 Tb/s.By proposing and experimentally validating an improved analytical model for inter-core spontaneous Raman scattering noise,we find that this configuration is optimal for our deployed MCF link as it is immune to four-wave mixing,that becomes relevant when the quantum and classical signals are propagating in the same direction.Our findings make an important step forward in demonstrating the integration of QKD and classical transmission in uncoupled-core multicore fibers for next-generation optical communication networks.展开更多
In order to solve the problems resulted from dynamic access control in a userhierarchy, a cryptographic key assignment scheme is proposed by Prof. Lin to promote the performingability and to simplify the procedure. Ho...In order to solve the problems resulted from dynamic access control in a userhierarchy, a cryptographic key assignment scheme is proposed by Prof. Lin to promote the performingability and to simplify the procedure. However, it may cause the security in danger as the userchanges his secret key; besides, some secret keys may be disclosed due to the unsuitable selectionof the security classes' identities. Through setting up a one-way hash function onto Lin's scheme,the proposed modification can greatly improve the security of Lin's scheme.展开更多
基金This project was supported by the National Science Foundation of China (60763009)China Postdoctoral Science Foundation (2005038041)Hainan Natural Science Foundation (80528).
文摘Two signature systems based on smart cards and fingerprint features are proposed. In one signature system, the cryptographic key is stored in the smart card and is only accessible when the signer＇s extracted fingerprint features match his stored template. To resist being tampered on public channel, the user＇s message and the signed message are encrypted by the signer＇s public key and the user＇s public key, respectively. In the other signature system, the keys are generated by combining the signer＇s fingerprint features, check bits, and a rememberable key, and there are no matching process and keys stored on the smart card. Additionally, there is generally more than one public key in this system, that is, there exist some pseudo public keys except a real one.
基金Funded by the visit scholar Foundation of the Electrooptical Technique & System key Lab of Chinese Ministry of Education in Chongqing.
文摘Watermarking is an effective approach to the copyright protection of digital media such as audio, image, and video. By inspiration from cryptography and considering the immensity of the set of all possible wavelets, it is presented that in wavelet domain watermarking, the associated wavelet can be considered as the private key for encrypting the watermark so as to enhance the security of the embedded mark. This idea is partly supported by the fact that from computational complexity viewpoint, it is very time-consuming to search over the immense set of all candidate wavelets for the right one if no a priori knowledge is known about it. To verify our proposal, the standard image 'Lena' is first watermarked in a specific wavelet domain, the watermark recovery experiments are then conducted in the wavelet domain for a set of wavelets with the one used for mark embedded in it,separately. It follows from the experimental results that the mark can be recovered only in the right wavelet domain, which justifies the suggestion.
基金funded by the European Commission through European Union—Next Generation EU,under the Italian National Recovery and Resilience Plan,Mission 4,Component 2,Investment 1.3,CUP B53C22003970001,partnership on“Telecommunications of the Future”(PE00000001—program“RESTART”)in the Digital Europe Program under project QUID(Quantum Italy Deployment)Grant Agreement 101091408funding from the European Commission through ERC StG,QOMUNE,Grant Agreement 101077917.
文摘Quantum key distribution(QKD)is a secure communication method for sharing symmetric cryptographic keys based on the principles of quantum physics.Its integration into the fiber-optic network infrastructure is important for ensuring privacy in optical communications.Multi-core fibers(MCFs),the likely building blocks of future high-capacity optical networks,offer new opportunities for such integration.Here,we experimentally demonstrate,for the first time,the coexistence of discrete-variable QKD and high-throughput classical communication in the C-band over a fielddeployed MCF with industry standard cladding diameter of 125μm.Specifically,we demonstrate successful secure-key establishment in one core of a 25.2-km uncoupled-core MCF,while simultaneously loading the remaining three cores with full C-band counter-propagating classical traffic at an aggregate net rate of 110.8 Tb/s.By proposing and experimentally validating an improved analytical model for inter-core spontaneous Raman scattering noise,we find that this configuration is optimal for our deployed MCF link as it is immune to four-wave mixing,that becomes relevant when the quantum and classical signals are propagating in the same direction.Our findings make an important step forward in demonstrating the integration of QKD and classical transmission in uncoupled-core multicore fibers for next-generation optical communication networks.
文摘In order to solve the problems resulted from dynamic access control in a userhierarchy, a cryptographic key assignment scheme is proposed by Prof. Lin to promote the performingability and to simplify the procedure. However, it may cause the security in danger as the userchanges his secret key; besides, some secret keys may be disclosed due to the unsuitable selectionof the security classes' identities. Through setting up a one-way hash function onto Lin's scheme,the proposed modification can greatly improve the security of Lin's scheme.
