Based on the state transition rule, the local updating rule and the global updating rule of ant colony algorithm, we propose an improved ant colony algorithm of the least\|cost quality of service (QoS) unicast rou...Based on the state transition rule, the local updating rule and the global updating rule of ant colony algorithm, we propose an improved ant colony algorithm of the least\|cost quality of service (QoS) unicast routing. The algorithm is used for solving the routing problem with delay, delay jitter, bandwidth, and packet loss\|constrained. In the simulation, about 52.33% ants find the successful QoS routing , and converge to the best. It is proved that the algorithm is efficient and effective.展开更多
Based on tht difficulty of solving the ECDLP (elliptic curve discretelogarithm problem) on the finite field, we present a (t, n) threshold signature scheme and averifiable key agreement scheme without trusted party. A...Based on tht difficulty of solving the ECDLP (elliptic curve discretelogarithm problem) on the finite field, we present a (t, n) threshold signature scheme and averifiable key agreement scheme without trusted party. Applying a modified elliptic curve signatureequation, we gel a more efficient signature scheme than the existing ECDSA (elliptic curve digitalsignature algorithm) from the computability and security view. Our scheme has a shorter key, fastercomputation, and better security.展开更多
Structural and statistical characteristics of signals can improve the performance of Compressed Sensing (CS). Two kinds of features of Discrete Cosine Transform (DCT) coefficients of voiced speech signals are discusse...Structural and statistical characteristics of signals can improve the performance of Compressed Sensing (CS). Two kinds of features of Discrete Cosine Transform (DCT) coefficients of voiced speech signals are discussed in this paper. The first one is the block sparsity of DCT coefficients of voiced speech formulated from two different aspects which are the distribution of the DCT coefficients of voiced speech and the comparison of reconstruction performance between the mixed program and Basis Pursuit (BP). The block sparsity of DCT coefficients of voiced speech means that some algorithms of block-sparse CS can be used to improve the recovery performance of speech signals. It is proved by the simulation results of the mixed program which is an improved version of the mixed program. The second one is the well known large DCT coefficients of voiced speech focus on low frequency. In line with this feature, a special Gaussian and Partial Identity Joint (GPIJ) matrix is constructed as the sensing matrix for voiced speech signals. Simulation results show that the GPIJ matrix outperforms the classical Gaussian matrix for speech signals of male and female adults.展开更多
The dual-containing (or self-orthogonal) formalism of Calderbank-Shor-Steane (CSS) codes provides a universal connection between a classical linear code and a Quantum Error-Correcting Code (QECC). We propose a novel c...The dual-containing (or self-orthogonal) formalism of Calderbank-Shor-Steane (CSS) codes provides a universal connection between a classical linear code and a Quantum Error-Correcting Code (QECC). We propose a novel class of quantum Low Density Parity Check (LDPC) codes constructed from cyclic classes of lines in Euclidean Geometry (EG). The corresponding constructed parity check matrix has quasi-cyclic structure that can be encoded flexibility, and satisfies the requirement of dual-containing quantum code. Taking the advantage of quasi-cyclic structure, we use a structured approach to construct Generalized Parity Check Matrix (GPCM). This new class of quantum codes has higher code rate, more sparse check matrix, and exactly one four-cycle in each pair of two rows. Ex-perimental results show that the proposed quantum codes, such as EG(2,q)II-QECC, EG(3,q)II-QECC, have better performance than that of other methods based on EG, over the depolarizing channel and decoded with iterative decoding based on the sum-product decoding algorithm.展开更多
Personal health record （PHR） enables patients to manage their own electronic medical records （EMR） in a centralized way, and it is oRen outsourced to be stored in a third-party server. In this paper we propose a n...Personal health record （PHR） enables patients to manage their own electronic medical records （EMR） in a centralized way, and it is oRen outsourced to be stored in a third-party server. In this paper we propose a novel secure and scalable system for sharing PHRs. We focus on the multiple data owner scenario, and divide the users in the system into multiple security domains that greatly reduce the key management complexity for owners and users. A high degree of patient privacy is guaranteed by exploiting hierarchical and multi- authority attribute-sets based encryption （HM- ASBE）. Our system not only supports compound attributes due to flexible attribute sets combinations, but also achieves fine-grained access control. Our scheme supports efficient on-demand user/attribute revocation and break-glass access under emergency scenarios.展开更多
Under Kerckhoff principle,this paper discusses the security property of an image encryp-tion scheme with a pseudorandom permutation.Some findings on the security problems of the algo-rithm are reported in the followin...Under Kerckhoff principle,this paper discusses the security property of an image encryp-tion scheme with a pseudorandom permutation.Some findings on the security problems of the algo-rithm are reported in the following:(1) If each row or column of the plain-image matrix is the same,the receiver cannot decrypt correctly.(2) Each plain-text word is correlated with single cipher-text word,but independent of other cipher-text word,which cannot meet the principles of algorithm design-diffusion and confusion.(3) If the cycle numbers are relatively small,statistics attack can be used to reveal some visual information of any other plain-images encrypted with the same secret key.Con-sidering the above problems,we propose an improved algorithm and then analyze its performance.Theoretical analysis and simulation results show that the improved algorithm can obtain better cryptographic properties,such as statistical characteristics,difference characteristics,and so on.展开更多
This paper introduces and analyzes a detection scheme for adaptive suppression of Multiuser Access Interference (MAI) and MultiPath Distortion (MPD) for mobile station of DS/CDMA system. The proposed detection scheme ...This paper introduces and analyzes a detection scheme for adaptive suppression of Multiuser Access Interference (MAI) and MultiPath Distortion (MPD) for mobile station of DS/CDMA system. The proposed detection scheme may amount to a RAKE receiver structure,wherein each branch is considered as a linear multiuser filter designed under a Linear Constrained Minimum Variance (LCMV) optimization strategy to suppress MAI, followed by a proper combining rule to suppress MPD. The adaptive blind multiuser detecting and optimum combining of the proposed receiver are realized, based on the Least-Mean-Square (LMS) algorithm and an adaptive vector tracking algorithm respectively. Finally, the feasibility of the above two algorithms is proved by the numerical results provided by computer simulation.展开更多
Claimed as the next generation programming paradigm, mobile agent technology has attracted extensive interests in recent years. However, up to now, limited research efforts have been devoted to the performance study o...Claimed as the next generation programming paradigm, mobile agent technology has attracted extensive interests in recent years. However, up to now, limited research efforts have been devoted to the performance study of mobile agent system and most of these researches focus on agent behavior analysis resulting in that models are hard to apply to mobile agent systems. To bridge the gap, a new performance evaluation model derived from operation mechanisms of mobile agent platforms is proposed. Details are discussed for the design of companion simulation software, which can provide the system performance such as response time of platform to mobile agent. Further investigation is followed on the determination of model parameters. Finally comparison is made between the model-based simulation results and measurement-based real performance of mobile agent systems. The results show that the proposed model and designed software are effective in evaluating performance characteristics of mobile agent systems. The proposed approach can also be considered as the basis of performance analysis for large systems composed of multiple mobile agent platforms.展开更多
With the scale of simulation system increasing rapidly, the distributed interactive simulation (DIS) faces the problem fo system scalability. One of main factors, which influence the DIS scalability, is that the lacks...With the scale of simulation system increasing rapidly, the distributed interactive simulation (DIS) faces the problem fo system scalability. One of main factors, which influence the DIS scalability, is that the lacks of standard defining interface methods, as the number of the system modules increased. This paper presents a method of defining an unified interface among different models. Then a DIS development platform based on it is established after thorough studies of the reasons that cause the DIS scalability problems. Finally we demonstrate the method by realization of an experiment DIS system in LAN environment. It validates that a practical system development can be carried out rapidly and efectively on this DIS development plaform. The experimental results show that the unified interface has general purpose for the design and implementation of DIS systems.展开更多
In this paper, a novel approach is presented to the multiuser channelidentification . The approach makes use of the modulation-induced Cyclostationarity, capable ofidentifying individual channels of different users. B...In this paper, a novel approach is presented to the multiuser channelidentification . The approach makes use of the modulation-induced Cyclostationarity, capable ofidentifying individual channels of different users. By means of the decomposition of the cyclicspectrum method, the blind estimation of the channel can be achieved . The approach is rathersimple, with considerable advantages over existing techniques, and suitable for the multiuser uplink. The identifiabilily condition and its proof are also concluded in the paper. And finally the.simulation of identification algorithm is given.展开更多
Parlay X is a set of simple and easy-understanding Application ProgrammingInterfaces (APIs), which abstract the fundamental functions of the telecommunication networks on thehigher layer than Parlay. Parlay X Web Serv...Parlay X is a set of simple and easy-understanding Application ProgrammingInterfaces (APIs), which abstract the fundamental functions of the telecommunication networks on thehigher layer than Parlay. Parlay X Web Service adopts Web Service technology to open services forIT developers to use in the applications they develop. In this paper, Web Service Flow Language(WSFL) is introduced to describe the services based on Parlay X Web Service, and an applicationinstance is presented.展开更多
The study of security in computer networks is a key issue, which is a rapidlygrowing area of interest because of its importance. Main network security problems are analyzed inthis paper above all, which currently are ...The study of security in computer networks is a key issue, which is a rapidlygrowing area of interest because of its importance. Main network security problems are analyzed inthis paper above all, which currently are confronted with network systems and existing works inintrusion detection. And then an intrusion detection system model based on Immune Principle (IPIDS)is presented. Meanwhile, it expatiates detailed implementation of the methods how to reduce the highfalse positive and negative alarms of the traditional Intrusion Detection System (IDS). At last asimple simulation is performed on this model just using string match algorithm as binding mechanism.The simulation results indicate that the model can detect malicious activity effectively, andconsequently the security and steadiness of the whole network system are improved also.展开更多
Active Networks represent a significant step in the evolution of packet-switched networks. It aims to move dynamic computation within the network. Mobile agent technology is a novel paradigm for distributed computatio...Active Networks represent a significant step in the evolution of packet-switched networks. It aims to move dynamic computation within the network. Mobile agent technology is a novel paradigm for distributed computation. This paper discusses the applicability of mobile agent technology for the development of active networks, both security policy and resource management, and other expected application as well. Based on the discussion, it describes a general mobile agent based Active Network (AN) architecture at last.展开更多
A special Modulation-Induced Cyclostationarity(MIC)scheme is designed for the identification and equaliza-tion of FIR Single-Input-Single-Output(SISO)channel,with the property that the transmit power is constant and t...A special Modulation-Induced Cyclostationarity(MIC)scheme is designed for the identification and equaliza-tion of FIR Single-Input-Single-Output(SISO)channel,with the property that the transmit power is constant and the re-ceiver needs only one antenna.The cyclic Wiener equalizer is presented based on the estimated channel.展开更多
In this paper, a joint semi blind channel estimation and data sequence detection of OFDM systems over the multipath frequency selective fading channels is proposed and investigated. The basic idea of the algorithm is...In this paper, a joint semi blind channel estimation and data sequence detection of OFDM systems over the multipath frequency selective fading channels is proposed and investigated. The basic idea of the algorithm is to first use the correlation among adjacent subchannels in the frequency domain to estimate the channel's parameters with an AutoRegressive (AR) process based on the decision directed estimation principle, and then to search the ML solution using the Viterbi algorithm. The algorithm realizes on line channel estimation and data detection of OFDM signals without any periodic pilot signal and statistic information about the channels, so it is suited to high data rate transmission over slow fading channels in the coming generation mobile communication systems.展开更多
With the development of network techniques, the problem of network securityis also arising as we enjoy its open convenience. There are many developed methods to overcome thisproblem. Identity authentication is one of ...With the development of network techniques, the problem of network securityis also arising as we enjoy its open convenience. There are many developed methods to overcome thisproblem. Identity authentication is one of these important measures. The authentication methods oftraditional symmetric cryptogram systems and asymmetric cryptogram systems have both advantages anddefects. This paper brings forward a Mixed Encryption Model for Authentication ( MEMA), which hasobvious advantages compared to the two traditional methods. MEMA model can be used widely in openingnetwork environment such as mobile agent systems, multi-agents security safeguard systems and othersituations in which identity authentication of users are needed. At last, the paper also presentsthe MEMA model's structure and implementation of an experimental system.展开更多
In this paper, we analyze the scheme of Space-Time Coded BeamForming (STC-BF)for the downlink of DS-CDMA system over frequency-selective fading channels and give the numericalsimulations on the scheme. The blind multi...In this paper, we analyze the scheme of Space-Time Coded BeamForming (STC-BF)for the downlink of DS-CDMA system over frequency-selective fading channels and give the numericalsimulations on the scheme. The blind multiuser detection is employed at receiver to suppress theMulti-Access Interference (MAI). The Space-Time Coding (STC) and BF are combined to mitigate theperformance degradation due to multipath fading and various interferences. The numerical simulationsshow that the BF can compensate the performance loss of STC due to the channel correlation and thenthe STC-BF can greatly improve the performance of CDMA system.展开更多
文摘Based on the state transition rule, the local updating rule and the global updating rule of ant colony algorithm, we propose an improved ant colony algorithm of the least\|cost quality of service (QoS) unicast routing. The algorithm is used for solving the routing problem with delay, delay jitter, bandwidth, and packet loss\|constrained. In the simulation, about 52.33% ants find the successful QoS routing , and converge to the best. It is proved that the algorithm is efficient and effective.
文摘Based on tht difficulty of solving the ECDLP (elliptic curve discretelogarithm problem) on the finite field, we present a (t, n) threshold signature scheme and averifiable key agreement scheme without trusted party. Applying a modified elliptic curve signatureequation, we gel a more efficient signature scheme than the existing ECDSA (elliptic curve digitalsignature algorithm) from the computability and security view. Our scheme has a shorter key, fastercomputation, and better security.
基金Supported by the National Natural Science Foundation of China (No. 60971129)the National Research Program of China (973 Program) (No. 2011CB302303)the Scientific Innovation Research Program of College Graduate in Jiangsu Province (No. CXLX11_0408)
文摘Structural and statistical characteristics of signals can improve the performance of Compressed Sensing (CS). Two kinds of features of Discrete Cosine Transform (DCT) coefficients of voiced speech signals are discussed in this paper. The first one is the block sparsity of DCT coefficients of voiced speech formulated from two different aspects which are the distribution of the DCT coefficients of voiced speech and the comparison of reconstruction performance between the mixed program and Basis Pursuit (BP). The block sparsity of DCT coefficients of voiced speech means that some algorithms of block-sparse CS can be used to improve the recovery performance of speech signals. It is proved by the simulation results of the mixed program which is an improved version of the mixed program. The second one is the well known large DCT coefficients of voiced speech focus on low frequency. In line with this feature, a special Gaussian and Partial Identity Joint (GPIJ) matrix is constructed as the sensing matrix for voiced speech signals. Simulation results show that the GPIJ matrix outperforms the classical Gaussian matrix for speech signals of male and female adults.
基金Supported by the National Natural Science Foundation ofChina (No. 61071145,41074090)the Specialized Research Fund for the Doctoral Program of Higher Education (200802880014)
文摘The dual-containing (or self-orthogonal) formalism of Calderbank-Shor-Steane (CSS) codes provides a universal connection between a classical linear code and a Quantum Error-Correcting Code (QECC). We propose a novel class of quantum Low Density Parity Check (LDPC) codes constructed from cyclic classes of lines in Euclidean Geometry (EG). The corresponding constructed parity check matrix has quasi-cyclic structure that can be encoded flexibility, and satisfies the requirement of dual-containing quantum code. Taking the advantage of quasi-cyclic structure, we use a structured approach to construct Generalized Parity Check Matrix (GPCM). This new class of quantum codes has higher code rate, more sparse check matrix, and exactly one four-cycle in each pair of two rows. Ex-perimental results show that the proposed quantum codes, such as EG(2,q)II-QECC, EG(3,q)II-QECC, have better performance than that of other methods based on EG, over the depolarizing channel and decoded with iterative decoding based on the sum-product decoding algorithm.
基金the National Natural Science Foundation of China under contract NO 61271235 and No.60973146,and the Fundamental Research Funds for the Central Universities under Grant No.BUPT2013RC0308
文摘Personal health record （PHR） enables patients to manage their own electronic medical records （EMR） in a centralized way, and it is oRen outsourced to be stored in a third-party server. In this paper we propose a novel secure and scalable system for sharing PHRs. We focus on the multiple data owner scenario, and divide the users in the system into multiple security domains that greatly reduce the key management complexity for owners and users. A high degree of patient privacy is guaranteed by exploiting hierarchical and multi- authority attribute-sets based encryption （HM- ASBE）. Our system not only supports compound attributes due to flexible attribute sets combinations, but also achieves fine-grained access control. Our scheme supports efficient on-demand user/attribute revocation and break-glass access under emergency scenarios.
基金Supported by the National Natural Science Foundation of China (No. 60874091)the Six Projects Sponsoring Talent Summits of Jiangsu Province (No. SJ209006)+2 种基金the Foundation for Doctoral Program of High Education of China(No. 20103223110003)the Natural Science Foundation of Jiangsu Province (No. 08KJD510022)the Post-graduate Scientific Innovation Project for Universities of Jiangsu Province (No. CXZZ11-0401)
文摘Under Kerckhoff principle,this paper discusses the security property of an image encryp-tion scheme with a pseudorandom permutation.Some findings on the security problems of the algo-rithm are reported in the following:(1) If each row or column of the plain-image matrix is the same,the receiver cannot decrypt correctly.(2) Each plain-text word is correlated with single cipher-text word,but independent of other cipher-text word,which cannot meet the principles of algorithm design-diffusion and confusion.(3) If the cycle numbers are relatively small,statistics attack can be used to reveal some visual information of any other plain-images encrypted with the same secret key.Con-sidering the above problems,we propose an improved algorithm and then analyze its performance.Theoretical analysis and simulation results show that the improved algorithm can obtain better cryptographic properties,such as statistical characteristics,difference characteristics,and so on.
文摘This paper introduces and analyzes a detection scheme for adaptive suppression of Multiuser Access Interference (MAI) and MultiPath Distortion (MPD) for mobile station of DS/CDMA system. The proposed detection scheme may amount to a RAKE receiver structure,wherein each branch is considered as a linear multiuser filter designed under a Linear Constrained Minimum Variance (LCMV) optimization strategy to suppress MAI, followed by a proper combining rule to suppress MPD. The adaptive blind multiuser detecting and optimum combining of the proposed receiver are realized, based on the Least-Mean-Square (LMS) algorithm and an adaptive vector tracking algorithm respectively. Finally, the feasibility of the above two algorithms is proved by the numerical results provided by computer simulation.
基金Supported by the National Natural Science Foundation of China (No.60072047) and Huawei Science and Technology Foundation (No.YJIN2003004)
文摘Claimed as the next generation programming paradigm, mobile agent technology has attracted extensive interests in recent years. However, up to now, limited research efforts have been devoted to the performance study of mobile agent system and most of these researches focus on agent behavior analysis resulting in that models are hard to apply to mobile agent systems. To bridge the gap, a new performance evaluation model derived from operation mechanisms of mobile agent platforms is proposed. Details are discussed for the design of companion simulation software, which can provide the system performance such as response time of platform to mobile agent. Further investigation is followed on the determination of model parameters. Finally comparison is made between the model-based simulation results and measurement-based real performance of mobile agent systems. The results show that the proposed model and designed software are effective in evaluating performance characteristics of mobile agent systems. The proposed approach can also be considered as the basis of performance analysis for large systems composed of multiple mobile agent platforms.
文摘With the scale of simulation system increasing rapidly, the distributed interactive simulation (DIS) faces the problem fo system scalability. One of main factors, which influence the DIS scalability, is that the lacks of standard defining interface methods, as the number of the system modules increased. This paper presents a method of defining an unified interface among different models. Then a DIS development platform based on it is established after thorough studies of the reasons that cause the DIS scalability problems. Finally we demonstrate the method by realization of an experiment DIS system in LAN environment. It validates that a practical system development can be carried out rapidly and efectively on this DIS development plaform. The experimental results show that the unified interface has general purpose for the design and implementation of DIS systems.
文摘In this paper, a novel approach is presented to the multiuser channelidentification . The approach makes use of the modulation-induced Cyclostationarity, capable ofidentifying individual channels of different users. By means of the decomposition of the cyclicspectrum method, the blind estimation of the channel can be achieved . The approach is rathersimple, with considerable advantages over existing techniques, and suitable for the multiuser uplink. The identifiabilily condition and its proof are also concluded in the paper. And finally the.simulation of identification algorithm is given.
基金This work is supported by ZTH Sciences Research Foundation(No.2003W24).
文摘Parlay X is a set of simple and easy-understanding Application ProgrammingInterfaces (APIs), which abstract the fundamental functions of the telecommunication networks on thehigher layer than Parlay. Parlay X Web Service adopts Web Service technology to open services forIT developers to use in the applications they develop. In this paper, Web Service Flow Language(WSFL) is introduced to describe the services based on Parlay X Web Service, and an applicationinstance is presented.
基金This work is sponsored by the National Natural Science Foundation of P. R. China (No.60173037 &70271050) National 863 High Technology Research Program ofP. R. China (No.2004AA775053) the Natural Science Foundation of Jiangsu Province (No.BK20031
文摘The study of security in computer networks is a key issue, which is a rapidlygrowing area of interest because of its importance. Main network security problems are analyzed inthis paper above all, which currently are confronted with network systems and existing works inintrusion detection. And then an intrusion detection system model based on Immune Principle (IPIDS)is presented. Meanwhile, it expatiates detailed implementation of the methods how to reduce the highfalse positive and negative alarms of the traditional Intrusion Detection System (IDS). At last asimple simulation is performed on this model just using string match algorithm as binding mechanism.The simulation results indicate that the model can detect malicious activity effectively, andconsequently the security and steadiness of the whole network system are improved also.
文摘Active Networks represent a significant step in the evolution of packet-switched networks. It aims to move dynamic computation within the network. Mobile agent technology is a novel paradigm for distributed computation. This paper discusses the applicability of mobile agent technology for the development of active networks, both security policy and resource management, and other expected application as well. Based on the discussion, it describes a general mobile agent based Active Network (AN) architecture at last.
文摘A special Modulation-Induced Cyclostationarity(MIC)scheme is designed for the identification and equaliza-tion of FIR Single-Input-Single-Output(SISO)channel,with the property that the transmit power is constant and the re-ceiver needs only one antenna.The cyclic Wiener equalizer is presented based on the estimated channel.
文摘In this paper, a joint semi blind channel estimation and data sequence detection of OFDM systems over the multipath frequency selective fading channels is proposed and investigated. The basic idea of the algorithm is to first use the correlation among adjacent subchannels in the frequency domain to estimate the channel's parameters with an AutoRegressive (AR) process based on the decision directed estimation principle, and then to search the ML solution using the Viterbi algorithm. The algorithm realizes on line channel estimation and data detection of OFDM signals without any periodic pilot signal and statistic information about the channels, so it is suited to high data rate transmission over slow fading channels in the coming generation mobile communication systems.
文摘With the development of network techniques, the problem of network securityis also arising as we enjoy its open convenience. There are many developed methods to overcome thisproblem. Identity authentication is one of these important measures. The authentication methods oftraditional symmetric cryptogram systems and asymmetric cryptogram systems have both advantages anddefects. This paper brings forward a Mixed Encryption Model for Authentication ( MEMA), which hasobvious advantages compared to the two traditional methods. MEMA model can be used widely in openingnetwork environment such as mobile agent systems, multi-agents security safeguard systems and othersituations in which identity authentication of users are needed. At last, the paper also presentsthe MEMA model's structure and implementation of an experimental system.
基金This work is supported by Jiangsu Provincial Natural Science Research Fund of China.
文摘In this paper, we analyze the scheme of Space-Time Coded BeamForming (STC-BF)for the downlink of DS-CDMA system over frequency-selective fading channels and give the numericalsimulations on the scheme. The blind multiuser detection is employed at receiver to suppress theMulti-Access Interference (MAI). The Space-Time Coding (STC) and BF are combined to mitigate theperformance degradation due to multipath fading and various interferences. The numerical simulationsshow that the BF can compensate the performance loss of STC due to the channel correlation and thenthe STC-BF can greatly improve the performance of CDMA system.
