LTE-A技术是在LTE(长期演进)技术基础上进一步提升的移动通信标准.随着LTE-A技术的快速发展,用户群日益扩大,使其成为潜在的、发展空间巨大的隐信道媒介.在本文中,我们基于LTE-A系统提出了一种新型的时序型鲁棒隐信道TCCBL(Timing Cover...LTE-A技术是在LTE(长期演进)技术基础上进一步提升的移动通信标准.随着LTE-A技术的快速发展,用户群日益扩大,使其成为潜在的、发展空间巨大的隐信道媒介.在本文中,我们基于LTE-A系统提出了一种新型的时序型鲁棒隐信道TCCBL(Timing Covert Channel Based on LTE-A).TCCBL利用包数据单元(PDU)头部中的序列号(SN)来选择传输隐蔽信息的数据包,然后利用所选中数据包负载中的附加位元来传输隐蔽信息.特别地,我们利用一个预先共享的哈希函数和一个独立的变量来实现不同的信息嵌入规则,保证了我们所设计隐信道的灵活性.展开更多
For the discontinuous occupancy of primary users in cognitive radio networks(CRN),the time-varying of spectrum holes becomes more and more highlighted.In the dynamic environment,cognitive users can access channels tha...For the discontinuous occupancy of primary users in cognitive radio networks(CRN),the time-varying of spectrum holes becomes more and more highlighted.In the dynamic environment,cognitive users can access channels that are not occupied by primary users,but they have to hand off to other spectrum holes to continue communication when primary users come back,which brings new security problems.Tracking user attack(TUA) is a typical attack during spectrum handoff,which will invalidate handoff by preventing user accessing,and break down the whole network.In this paper,we propose a Channel Selection Information Hiding scheme(CSIH) to defense TUA.With the proposed scheme,we can destroy the routes to the root node of the attack tree by hiding the information of channel selection and enhance the security of cognitive radio networks.展开更多
The proposed secure communication approach adopts the proposed algorithm of Analysis-By- Synthesis (ABS) speech information hiding to establish a Secret Speech Subliminai Channel (SSSC) for speech secure communica...The proposed secure communication approach adopts the proposed algorithm of Analysis-By- Synthesis (ABS) speech information hiding to establish a Secret Speech Subliminai Channel (SSSC) for speech secure communication over PSTN (Public Switched Telephone Network), and employs the algorithm of ABS speech information extracting to recovery the secret information, This approach is more reliable, covert and securable than traditional and chaotic secure communication.展开更多
Channel estimation using pilot is common used in OFDM system.The pilot is usually time division multiplexed with the informative sequence.One of the main drawbacks is bandwidth losing.In this paper,a new method was pr...Channel estimation using pilot is common used in OFDM system.The pilot is usually time division multiplexed with the informative sequence.One of the main drawbacks is bandwidth losing.In this paper,a new method was proposed to perform channel estimation in OFDM system.The pilot is arithmetically added to the output of OFDM modulator.Receiver uses the hidden pilot to get an accurate estimation of the channel.Then pilot is removed after channel estimation.The Cramer-Rao lower bound for this method was deprived.The performance of the algorithm is then shown.Compared with traditional methods,the proposed algorithm increases the bandwidth efficiency dramatically.展开更多
Two types of new subliminal channels are constructed respectively based on provable secure public key cryptosystems and identity recognition in some network applications. Research shows that there are some new charact...Two types of new subliminal channels are constructed respectively based on provable secure public key cryptosystems and identity recognition in some network applications. Research shows that there are some new characteristics which are in favor of covert communication in our constructions. It is hard to make the subliminal channels free, and the channels have large capacity and high transmission efficiency. We also point out that the hardness to make the channels free is disadvantageous to the warden who tries to thwart the covert communication.展开更多
文摘LTE-A技术是在LTE(长期演进)技术基础上进一步提升的移动通信标准.随着LTE-A技术的快速发展,用户群日益扩大,使其成为潜在的、发展空间巨大的隐信道媒介.在本文中,我们基于LTE-A系统提出了一种新型的时序型鲁棒隐信道TCCBL(Timing Covert Channel Based on LTE-A).TCCBL利用包数据单元(PDU)头部中的序列号(SN)来选择传输隐蔽信息的数据包,然后利用所选中数据包负载中的附加位元来传输隐蔽信息.特别地,我们利用一个预先共享的哈希函数和一个独立的变量来实现不同的信息嵌入规则,保证了我们所设计隐信道的灵活性.
基金国家自然科学基金青年科学基金项目(60803015)中国博士后基金项目(20080430902)+8 种基金黑龙江省教育厅科学技术研究重点项目(1154Z1001)黑龙江省博士后基金项目(LRB08-021)黑龙江省科技计划基金项目(QC04C40)黑龙江省教育厅科学技术研究指导项目(1153304511531276)黑龙江省研究生创新科研项目(YJSCX2009-019 HLJ)哈尔滨市青年科技创新人才研究专项基金项目(2008RFQXG1072009RFQXG080)supported by the National Natural Science Foundation of China for Young Scholar
基金the National Natural Science Foundation of China under Grant No.61172068,6137317 0.The Fundamental Research Funds for the Central Universities,Program for New Century Excellent Talents in University
文摘For the discontinuous occupancy of primary users in cognitive radio networks(CRN),the time-varying of spectrum holes becomes more and more highlighted.In the dynamic environment,cognitive users can access channels that are not occupied by primary users,but they have to hand off to other spectrum holes to continue communication when primary users come back,which brings new security problems.Tracking user attack(TUA) is a typical attack during spectrum handoff,which will invalidate handoff by preventing user accessing,and break down the whole network.In this paper,we propose a Channel Selection Information Hiding scheme(CSIH) to defense TUA.With the proposed scheme,we can destroy the routes to the root node of the attack tree by hiding the information of channel selection and enhance the security of cognitive radio networks.
基金Supported by the National High Technology Research and Development Program of China (863 Program) (No.2003AA142080, 2004AA775060)the National Natural Sicence Foundation of China (No.60203004)+1 种基金with additional support from the China Post-doctorial Research Foundation (2005-03)the Foundation of Tianjin Key Lab for Advanced Signal Processing(2005).
文摘The proposed secure communication approach adopts the proposed algorithm of Analysis-By- Synthesis (ABS) speech information hiding to establish a Secret Speech Subliminai Channel (SSSC) for speech secure communication over PSTN (Public Switched Telephone Network), and employs the algorithm of ABS speech information extracting to recovery the secret information, This approach is more reliable, covert and securable than traditional and chaotic secure communication.
基金The National Natural Science Foundation ofChina(No.60332030)The National High Technology Research and Development Pro-gram of China(863Program)(No.2003AA123310)
文摘Channel estimation using pilot is common used in OFDM system.The pilot is usually time division multiplexed with the informative sequence.One of the main drawbacks is bandwidth losing.In this paper,a new method was proposed to perform channel estimation in OFDM system.The pilot is arithmetically added to the output of OFDM modulator.Receiver uses the hidden pilot to get an accurate estimation of the channel.Then pilot is removed after channel estimation.The Cramer-Rao lower bound for this method was deprived.The performance of the algorithm is then shown.Compared with traditional methods,the proposed algorithm increases the bandwidth efficiency dramatically.
基金Supported by the National Outstanding Natural Science Foundation of China(No.90104005)
文摘Two types of new subliminal channels are constructed respectively based on provable secure public key cryptosystems and identity recognition in some network applications. Research shows that there are some new characteristics which are in favor of covert communication in our constructions. It is hard to make the subliminal channels free, and the channels have large capacity and high transmission efficiency. We also point out that the hardness to make the channels free is disadvantageous to the warden who tries to thwart the covert communication.