The nature of adhoc networks makes them vulnerable to security attacks. Many security technologies such as intrusion prevention and intrusion detection are passive in response to intrusions in that their countermea- s...The nature of adhoc networks makes them vulnerable to security attacks. Many security technologies such as intrusion prevention and intrusion detection are passive in response to intrusions in that their countermea- sures are only to protect the networks, and there is no automated network-wide counteraction against detected intrusions, the architecture of cooperation intrusion response based multi-agent is propose. The architecture is composed of mobile agents. Monitor agent resides on every node and monitors its neighbor nodes. Decision agent collects information from monitor nodes and detects an intrusion by security policies. When an intruder is found in the architecture, the block agents will get to the neighbor nodes of the intruder and form the mobile firewall to isolate the intruder. In the end, we evaluate it by simulation.展开更多
A new 5-round distinguisher of AES with key whitening is presented by using the properties of its round transformation. Based on this distinguisher,we present new meet-in-the-middle attacks on reduced AES considering ...A new 5-round distinguisher of AES with key whitening is presented by using the properties of its round transformation. Based on this distinguisher,we present new meet-in-the-middle attacks on reduced AES considering the key schedule and the time-memory tradeoff approach. New attacks improve the best known meet-in-the-middle attacks on reduced AES presented at FSE2008.We reduce the time complexity of attacks on 7-round AES-192 and 8-round AES-256 by a factor of at least 28. Moreover,the distinguisher can be exploited to develop the attack on 8-round AES-192.展开更多
E-lottery is a popular game for its convenience provided by the lnternet. An e-lottery scheme based on voting is proposed. The scheme is publicly verifiable and the fairness can be guaranteed. Lottery players not only...E-lottery is a popular game for its convenience provided by the lnternet. An e-lottery scheme based on voting is proposed. The scheme is publicly verifiable and the fairness can be guaranteed. Lottery players not only provide seed numbers to create the initial value of the lucky number, but also have an opportunity to change the intermediate value of the lucky number by means of voting. The new property of the scheme makes the lottery game more interactive and attractive to players. The anonymity of submitting the lottery ticket and casting the vote is achieved. Comparison with other existing elottery schemes is given.展开更多
The real polynomial type public-key cryptosystems are broken up by computing the equivalent secure keys, then some computational problems related to securities of cryptosystems are discussed.
For steganalysis of JPEG images,features derived in the embedding domain appear to achieve a preferable performance.However,with the existing JPEG steganography,the minor changes due to the hidden secret data are not ...For steganalysis of JPEG images,features derived in the embedding domain appear to achieve a preferable performance.However,with the existing JPEG steganography,the minor changes due to the hidden secret data are not easy to be explored directly from the quantized block DCT(BDCT)coefficients in that the energy of the carrier image is much larger than that of the hidden signal.In this paper,we present an improved calibration-based universal JPEG steganalysis,where the microscopic and macroscopic calibrations are combined to calibrate the local and global distribution of the quantized BDCT coefficients of the test image.All features in our method are generated from the difference signal be-tween the quantized BDCT coefficients of the test image and its corresponding microscopic calibrated image,or calculated as the difference between the signal extracted from test image and its corresponding macroscopic calibrated image.The extracted features will be more effective for our classification.Moreover,through using the Markov empirical transition matrices,both magnitude and sign dependencies along row scanning and column scanning patterns existed in intra-block and inter-block quantized BDCT coefficients are employed in our method.Experimental results demonstrate that our proposed scheme outperforms the best effective JPEG steganalyzers having been presented.展开更多
Malicious applications can be introduced to attack users and services so as to gain financial rewards, individuals＇ sensitive information, company and government intellectual property, and to gain remote control of s...Malicious applications can be introduced to attack users and services so as to gain financial rewards, individuals＇ sensitive information, company and government intellectual property, and to gain remote control of systems. However, traditional methods of malicious code detection, such as signature detection, behavior detection, virtual machine detection, and heuristic detection, have various weaknesses which make them unreliable. This paper presents the existing technologies of malicious code detection and a malicious code detection model is proposed based on behavior association. The behavior points of malicious code are first extracted through API monitoring technology and integrated into the behavior; then a relation between behaviors is established according to data dependence. Next, a behavior association model is built up and a discrimination method is put forth using pushdown automation. Finally, the exact malicious code is taken as a sample to carry out an experiment on the behavior＇s capture, association, and discrimination, thus proving that the theoretical model is viable.展开更多
Sequences with ideal correlation functions have important applications in communications such as CDMA,FDMA,etc.It has been shown that difference sets can be used to construct such sequences.The author extends Pott and...Sequences with ideal correlation functions have important applications in communications such as CDMA,FDMA,etc.It has been shown that difference sets can be used to construct such sequences.The author extends Pott and Bradley's method to a much broader case by proposing the concept of generalized difference sets.Some necessary conditions for the existence of generalized difference sets are established by means of some Diophantine equations.The author also provides an algorithm to determine the existence of generalized difference sets in the cyclic group Zv.Some examples are presented to illustrate that our method works.展开更多
基金This project was supported by the National Natural Science Foundation of China (60672068)the National High Technology Development 863 Program of China (2006AA01Z436, 2007AA01Z452.)
文摘The nature of adhoc networks makes them vulnerable to security attacks. Many security technologies such as intrusion prevention and intrusion detection are passive in response to intrusions in that their countermea- sures are only to protect the networks, and there is no automated network-wide counteraction against detected intrusions, the architecture of cooperation intrusion response based multi-agent is propose. The architecture is composed of mobile agents. Monitor agent resides on every node and monitors its neighbor nodes. Decision agent collects information from monitor nodes and detects an intrusion by security policies. When an intruder is found in the architecture, the block agents will get to the neighbor nodes of the intruder and form the mobile firewall to isolate the intruder. In the end, we evaluate it by simulation.
基金supported by the Nature Science Foundation of China under grant 60970119, 60833008the National Basic Research Program of China(973) under grant 2007CB311201the Fundamental Research Funds for the Central Universities under grant K50510010018
文摘A new 5-round distinguisher of AES with key whitening is presented by using the properties of its round transformation. Based on this distinguisher,we present new meet-in-the-middle attacks on reduced AES considering the key schedule and the time-memory tradeoff approach. New attacks improve the best known meet-in-the-middle attacks on reduced AES presented at FSE2008.We reduce the time complexity of attacks on 7-round AES-192 and 8-round AES-256 by a factor of at least 28. Moreover,the distinguisher can be exploited to develop the attack on 8-round AES-192.
文摘E-lottery is a popular game for its convenience provided by the lnternet. An e-lottery scheme based on voting is proposed. The scheme is publicly verifiable and the fairness can be guaranteed. Lottery players not only provide seed numbers to create the initial value of the lucky number, but also have an opportunity to change the intermediate value of the lucky number by means of voting. The new property of the scheme makes the lottery game more interactive and attractive to players. The anonymity of submitting the lottery ticket and casting the vote is achieved. Comparison with other existing elottery schemes is given.
基金Supported by the National Natural Science Foundation of Chinathe Fund of the State Education Commission of China
文摘The real polynomial type public-key cryptosystems are broken up by computing the equivalent secure keys, then some computational problems related to securities of cryptosystems are discussed.
基金Supported by the National Basic Research Program of China(Grant No.2006CB303104)the National Natural Science Foundation of China(Grant Nos.90604008 and 60633030)the Research Fund for the Doctoral Program of Higher Education of China(Grant No.20070558054)
文摘For steganalysis of JPEG images,features derived in the embedding domain appear to achieve a preferable performance.However,with the existing JPEG steganography,the minor changes due to the hidden secret data are not easy to be explored directly from the quantized block DCT(BDCT)coefficients in that the energy of the carrier image is much larger than that of the hidden signal.In this paper,we present an improved calibration-based universal JPEG steganalysis,where the microscopic and macroscopic calibrations are combined to calibrate the local and global distribution of the quantized BDCT coefficients of the test image.All features in our method are generated from the difference signal be-tween the quantized BDCT coefficients of the test image and its corresponding microscopic calibrated image,or calculated as the difference between the signal extracted from test image and its corresponding macroscopic calibrated image.The extracted features will be more effective for our classification.Moreover,through using the Markov empirical transition matrices,both magnitude and sign dependencies along row scanning and column scanning patterns existed in intra-block and inter-block quantized BDCT coefficients are employed in our method.Experimental results demonstrate that our proposed scheme outperforms the best effective JPEG steganalyzers having been presented.
基金supported by the National Natural Science Foundation of China (Nos. 61272033 and 61272405)
文摘Malicious applications can be introduced to attack users and services so as to gain financial rewards, individuals＇ sensitive information, company and government intellectual property, and to gain remote control of systems. However, traditional methods of malicious code detection, such as signature detection, behavior detection, virtual machine detection, and heuristic detection, have various weaknesses which make them unreliable. This paper presents the existing technologies of malicious code detection and a malicious code detection model is proposed based on behavior association. The behavior points of malicious code are first extracted through API monitoring technology and integrated into the behavior; then a relation between behaviors is established according to data dependence. Next, a behavior association model is built up and a discrimination method is put forth using pushdown automation. Finally, the exact malicious code is taken as a sample to carry out an experiment on the behavior＇s capture, association, and discrimination, thus proving that the theoretical model is viable.
基金National Natural Science Foundation of China under Grant No.10771100
文摘Sequences with ideal correlation functions have important applications in communications such as CDMA,FDMA,etc.It has been shown that difference sets can be used to construct such sequences.The author extends Pott and Bradley's method to a much broader case by proposing the concept of generalized difference sets.Some necessary conditions for the existence of generalized difference sets are established by means of some Diophantine equations.The author also provides an algorithm to determine the existence of generalized difference sets in the cyclic group Zv.Some examples are presented to illustrate that our method works.
