由于空间链路固有的开放性,国际空间数据系统咨询委员会(Consultative Committee for Space Data Systems,CCSDS)建立的空间数据系统面临着窃听、篡改、伪装等安全威胁,因此研究CCSDS空间数据系统链路层的安全协议和安全技术十分重要....由于空间链路固有的开放性,国际空间数据系统咨询委员会(Consultative Committee for Space Data Systems,CCSDS)建立的空间数据系统面临着窃听、篡改、伪装等安全威胁,因此研究CCSDS空间数据系统链路层的安全协议和安全技术十分重要.研究基于CCSDS空间通信系统链路层遥控(Telecommand,TC)协议采用的加密、认证及认证加密等安全技术,分析了TC协议为用户提供的服务,TC使用的协议数据单元和协议执行规程,研究了空间数据链路安全(Space Data Link Security,SDLS)协议为CCSDS链路协议提供的加密、认证和认证加密等安全服务的原理和协议执行规程,并利用OPNET网络仿真平台对使用SDLS协议的TC协议的协议规程进行了实现与仿真,验证了通过SDLS协议将安全技术应用于TC协议的正确性和可行性.结果表明,SDLS协议采用的加密、认证及认证加密等安全技术可以为CCSDS链路层的协议提供安全防护,为真实的空间通信网络的通信安全提供技术支持和重要保障.展开更多
Chain length of closed circle DNA is equal. The same closed circle DNA's position corresponds to different recognition sequence, and the same recognition sequence corresponds to different foreign DNA segment, so clos...Chain length of closed circle DNA is equal. The same closed circle DNA's position corresponds to different recognition sequence, and the same recognition sequence corresponds to different foreign DNA segment, so closed circle DNA computing model is generalized. For change positive-weighted Hamilton circuit problem, closed circle DNA algorithm is put forward. First, three groups of DNA encoding are encoded for all arcs, and deck groups are designed for all vertices. All possible solutions are composed. Then, the feasible solutions are filtered out by using group detect experiment, and the optimization solutions are obtained by using group insert experiment and electrophoresis experiment. Finally, all optimization solutions are found by using detect experiment. Complexity of algorithm is concluded and validity of DNA algorithm is explained by an example. Three dominances of the closed circle DNA algorithm are analyzed, and characteristics and dominances of group delete experiment are discussed.展开更多
Chaotic cryptography has been applied to image encryption;however,only the traditional low-dimensional chaotic systems has been widely analyzed or deciphered,which does not show satisfied security and efficiency.To so...Chaotic cryptography has been applied to image encryption;however,only the traditional low-dimensional chaotic systems has been widely analyzed or deciphered,which does not show satisfied security and efficiency.To solve this problem,a new algorithm based on cross-chaos map has been created in this article.The image pixels are scrambled under control of high-dimensional chaotic sequence,which is generated by cross chaotic map.The image pixels are substituted by ciphertext feedback algorithm.It can relate encryption required parameters with plaintext and can make a plaintext byte affect more ciphertext bytes.Proved by theoretical analysis and experimental results,the algorithm has higher complex degree and has passed SP800-22 pseudo-random number standard tests,and it has high encryption speed,high security,etc.It can be widely applied in the field of image encryption.展开更多
文摘由于空间链路固有的开放性,国际空间数据系统咨询委员会(Consultative Committee for Space Data Systems,CCSDS)建立的空间数据系统面临着窃听、篡改、伪装等安全威胁,因此研究CCSDS空间数据系统链路层的安全协议和安全技术十分重要.研究基于CCSDS空间通信系统链路层遥控(Telecommand,TC)协议采用的加密、认证及认证加密等安全技术,分析了TC协议为用户提供的服务,TC使用的协议数据单元和协议执行规程,研究了空间数据链路安全(Space Data Link Security,SDLS)协议为CCSDS链路协议提供的加密、认证和认证加密等安全服务的原理和协议执行规程,并利用OPNET网络仿真平台对使用SDLS协议的TC协议的协议规程进行了实现与仿真,验证了通过SDLS协议将安全技术应用于TC协议的正确性和可行性.结果表明,SDLS协议采用的加密、认证及认证加密等安全技术可以为CCSDS链路层的协议提供安全防护,为真实的空间通信网络的通信安全提供技术支持和重要保障.
基金supported by the National Natural Science Foundation of China(60574041)the Natural ScienceFoundation of Hubei Province(2007ABA407).
文摘Chain length of closed circle DNA is equal. The same closed circle DNA's position corresponds to different recognition sequence, and the same recognition sequence corresponds to different foreign DNA segment, so closed circle DNA computing model is generalized. For change positive-weighted Hamilton circuit problem, closed circle DNA algorithm is put forward. First, three groups of DNA encoding are encoded for all arcs, and deck groups are designed for all vertices. All possible solutions are composed. Then, the feasible solutions are filtered out by using group detect experiment, and the optimization solutions are obtained by using group insert experiment and electrophoresis experiment. Finally, all optimization solutions are found by using detect experiment. Complexity of algorithm is concluded and validity of DNA algorithm is explained by an example. Three dominances of the closed circle DNA algorithm are analyzed, and characteristics and dominances of group delete experiment are discussed.
基金Supported by the National Natural Science Foundation of China (60973162)the Natural Science Foundation of Shandong Province of China (ZR2009GM037)+2 种基金the Science and Technology Project of Shandong Province,China (2010GGX10132,2012GGX10110)the Key Natural Science Foundation of Shan-dong Province of China (Z2006G01)the Soft Science Project of Shangdong Province of China (2012RKA10009)
文摘Chaotic cryptography has been applied to image encryption;however,only the traditional low-dimensional chaotic systems has been widely analyzed or deciphered,which does not show satisfied security and efficiency.To solve this problem,a new algorithm based on cross-chaos map has been created in this article.The image pixels are scrambled under control of high-dimensional chaotic sequence,which is generated by cross chaotic map.The image pixels are substituted by ciphertext feedback algorithm.It can relate encryption required parameters with plaintext and can make a plaintext byte affect more ciphertext bytes.Proved by theoretical analysis and experimental results,the algorithm has higher complex degree and has passed SP800-22 pseudo-random number standard tests,and it has high encryption speed,high security,etc.It can be widely applied in the field of image encryption.