To realize delegation between different users in a mixed cryptosystem,a proxy signature scheme for ID-based original signers and certificated-based proxy signers(PSS-ID-CER)is defined.Using the bilinear properties o...To realize delegation between different users in a mixed cryptosystem,a proxy signature scheme for ID-based original signers and certificated-based proxy signers(PSS-ID-CER)is defined.Using the bilinear properties of the pairings and the characters of key generations of certificate-based cryptosystems and ID-based cryptosystems,a construction for such a scheme is also presented.To prove the security of the proposed scheme,a general security model for this scheme under adaptive chosen-PKG,chosen-ID,chosen-delegation,chosen-ProxySigner-public-key,chosen-proxy-key and chosen-message attack is defined.The proposed scheme is provably secure under the random oracle model and the hardness assumption of computational Diffie-Hellman problem.展开更多
The basic idea behind an ID-based cryptosystem is that end user's public key can be determined by his identity information.Comparing with the traditional certificate-based cryptography,identity-based cryptography ...The basic idea behind an ID-based cryptosystem is that end user's public key can be determined by his identity information.Comparing with the traditional certificate-based cryptography,identity-based cryptography can eliminate much of the overhead associated with the deployment and management of certificate.However,exposure of private keys can be the most devastating attack on a public key based cryptosystem since such that all security guarantees are lost.In this paper,an ID-based authenticated key agreement protocol was presented.For solving the problem of key exposure of the basic scheme,the technique of key insulation was applied and a key insulated version is developed.展开更多
ID-based public key cryptosystem can be a good alternative for certifieate-based public key setting. This paper provides an efficient ID-based proxy multi signature scheme from pairings. In the random oracle model, we...ID-based public key cryptosystem can be a good alternative for certifieate-based public key setting. This paper provides an efficient ID-based proxy multi signature scheme from pairings. In the random oracle model, we prove that our new scheme is secure against existential delegation forgery with the assumption that Hess's scheme-1 is existential unforgeable, and that our new scheme is secure against existential proxy multi-signature forgery under the hardness assumption of the computational Diffie-Hellman problem.展开更多
Cloud storage service reduces the burden of data users by storing users' data files in the cloud. But, the files might be modified in the cloud. So, data users hope to check data files integrity periodically. In a pu...Cloud storage service reduces the burden of data users by storing users' data files in the cloud. But, the files might be modified in the cloud. So, data users hope to check data files integrity periodically. In a public auditing protocol, there is a trusted auditor who has certain ability to help users to check the integrity of data files. With the advantages of no public key management and verification, researchers focus on public auditing protocol in ID-based cryptography recently. However, some existing protocols are vulnerable to forgery attack. In this paper, based on ID-based signature technology, by strengthening information authentication and the computing power of the auditor, we propose an ID-based public auditing protocol for cloud data integrity checking. We also prove that the proposed protocol is secure in the random oracle model under the assumption that the Diffie-Hellman problem is hard. Furthermore, we compare the proposed protocol with other two ID-based auditing protocols in security features, communication efficiency and computation cost. The comparisons show that the proposed protocol satisfies more security features with lower computation cost.展开更多
Identity-based proxy signature enables an entity to delegate its signing rights to another entity in identity-based cryptosystem settings. However, few existing scheme has been proved secure in a formalized model, or ...Identity-based proxy signature enables an entity to delegate its signing rights to another entity in identity-based cryptosystem settings. However, few existing scheme has been proved secure in a formalized model, or acquired optimized performance. To achieve the goals of both proven security and high efficiency, this paper proposed an efficient identity-based proxy signature scheme. The scheme is constructed from bilinear pairing and proved secure in the random oracle model, using the oracle replay attack technique introduced by Pointehval and Stern. The analysis shows that the scheme needs less computation costs and has a shorter signature than the other schemes.展开更多
In existing software registration schemes, the privacy of users is not taken into account and may be in the risks of abuses. In this paper, we proposed a novel software registration system which can greatly reduce una...In existing software registration schemes, the privacy of users is not taken into account and may be in the risks of abuses. In this paper, we proposed a novel software registration system which can greatly reduce unauthorized use of software while keeping the privacy of users. To the best of our knowledge, this is the first system that the privacy of users is guaranteed in software registration. Our system enjoys a modular design and can be implemented by any secure ID-based partially blind signature scheme. Furthermore, the proposal allows flexible registration information definition. This feature makes our scheme flexible and practical for more software registration applications.展开更多
In the last couple of years, D-based cryptography has got fruitful achievements. Proxy multi-signature allows a designated person, called a proxy signer, to sign on behalf of two or more original signers. In this pape...In the last couple of years, D-based cryptography has got fruitful achievements. Proxy multi-signature allows a designated person, called a proxy signer, to sign on behalf of two or more original signers. In this paper, we present a general security model for ID-based proxy multi-signature (ID-PMS) schemes. Then, we show how to construct a secure ID-PMS scheme from a secure ID-based signature scheme, and prove that the security of the construction can be reduced to the security of the original ID-based signature scheme.展开更多
Two ID-based authenticated group key agreement schemes, proposed by Choi et al and Du et al, are insecure against an impersonation attack and th ey only discussed the static group. This paper proposed a variant of BD ...Two ID-based authenticated group key agreement schemes, proposed by Choi et al and Du et al, are insecure against an impersonation attack and th ey only discussed the static group. This paper proposed a variant of BD protocol , which is fully authenticated by a proven-secure ID-based signature scheme. T he protocol can res ist the impersonation attack, and other security attributes are also satisfied. Compared with Choi et al and Du et al schemes, the proposed one is mor e efficient and applicable for dynamic groups.展开更多
Peer-to-peer computing has recently started to gain significant acceptance, since it can greatly increase the performance and reliability of overall system. However, the security issue is still a major gating factor f...Peer-to-peer computing has recently started to gain significant acceptance, since it can greatly increase the performance and reliability of overall system. However, the security issue is still a major gating factor for its full adoption. In order to guarantee the security of data exchanged between two peers in Peer-to-Peer system, this paper comes up with an ID-based authenticated key agreement from bilinear pairings and uses BAN logic to prove the protocol’s security. Compared with other existing protocols, the proposed protocol seems more secure and efficient, since it adopts the static shared Diffie-Hellman key.展开更多
Key escrow is an inherent disadvantage for traditional ID-based cryptosystem, i.e., the dishonest private key generator (PKG) can forge the signature of any user, meanwhile, the user can deny the signature actually si...Key escrow is an inherent disadvantage for traditional ID-based cryptosystem, i.e., the dishonest private key generator (PKG) can forge the signature of any user, meanwhile, the user can deny the signature actually signed by him/herself. To avoid the keyescrow problem, an ID-based signature scheme was presented without trusted PKG. The exact proof of security was presented to demonstrate that our scheme is secure against existential forgery on adaptively chosen message and ID attacks assuming the complexity of computational Diffie-Hellman (CDH) problem. Compared with other signature schemes, the proposed scheme is more efficient.展开更多
This paper presents a high-security medical image encryption method that leverages a novel and robust sine-cosine map.The map demonstrates remarkable chaotic dynamics over a wide range of parameters.We employ nonlinea...This paper presents a high-security medical image encryption method that leverages a novel and robust sine-cosine map.The map demonstrates remarkable chaotic dynamics over a wide range of parameters.We employ nonlinear analytical tools to thoroughly investigate the dynamics of the chaotic map,which allows us to select optimal parameter configurations for the encryption process.Our findings indicate that the proposed sine-cosine map is capable of generating a rich variety of chaotic attractors,an essential characteristic for effective encryption.The encryption technique is based on bit-plane decomposition,wherein a plain image is divided into distinct bit planes.These planes are organized into two matrices:one containing the most significant bit planes and the other housing the least significant ones.The subsequent phases of chaotic confusion and diffusion utilize these matrices to enhance security.An auxiliary matrix is then generated,comprising the combined bit planes that yield the final encrypted image.Experimental results demonstrate that our proposed technique achieves a commendable level of security for safeguarding sensitive patient information in medical images.As a result,image quality is evaluated using the Structural Similarity Index(SSIM),yielding values close to zero for encrypted images and approaching one for decrypted images.Additionally,the entropy values of the encrypted images are near 8,with a Number of Pixel Change Rate(NPCR)and Unified Average Change Intensity(UACI)exceeding 99.50%and 33%,respectively.Furthermore,quantitative assessments of occlusion attacks,along with comparisons to leading algorithms,validate the integrity and efficacy of our medical image encryption approach.展开更多
The Industry 4.0 revolution is characterized by distributed infrastructures where data must be continuously communicated between hardware nodes and cloud servers.Specific lightweight cryptosystems are needed to protec...The Industry 4.0 revolution is characterized by distributed infrastructures where data must be continuously communicated between hardware nodes and cloud servers.Specific lightweight cryptosystems are needed to protect those links,as the hardware node tends to be resource-constrained.Then Pseudo Random Number Generators are employed to produce random keys,whose final behavior depends on the initial seed.To guarantee good mathematical behavior,most key generators need an unpredictable voltage signal as input.However,physical signals evolve slowly and have a significant autocorrelation,so they do not have enough entropy to support highrandomness seeds.Then,electronic mechanisms to generate those high-entropy signals artificially are required.This paper proposes a robust hyperchaotic circuit to obtain such unpredictable electric signals.The circuit is based on a hyperchaotic dynamic system,showing a large catalog of structures,four different secret parameters,and producing four high entropy voltage signals.Synchronization schemes for the correct secret key calculation and distribution among all remote communicating modules are also analyzed and discussed.Security risks and intruder and attacker models for the proposed solution are explored,too.An experimental validation based on circuit simulations and a real hardware implementation is provided.The results show that the random properties of PRNG improved by up to 11%when seeds were calculated through the proposed circuit.展开更多
This study deals with the dynamic property of threshold cryptosystem. A dynamic threshold cryptosystem allows the sender to choose the authorized decryption group and the threshold value for each message dynamically. ...This study deals with the dynamic property of threshold cryptosystem. A dynamic threshold cryptosystem allows the sender to choose the authorized decryption group and the threshold value for each message dynamically. We first introduce an identity based dynamic threshold cryptosystem, and then use the CanettiHalevi-Katz(CHK) transformation to transform it into a fully secure system in the traditional public key setting.Finally, the elegant dual system encryption technique is applied to constructing a fully secure dynamic threshold cryptosystem with adaptive security.展开更多
An enhaned NTRU cryptosystem eliminating decryption failures is proposed without using padding schemes and can resist the oracle model andchosen-ciphertext attacks. Because lattice reduction is the main threat to latt...An enhaned NTRU cryptosystem eliminating decryption failures is proposed without using padding schemes and can resist the oracle model andchosen-ciphertext attacks. Because lattice reduction is the main threat to lattice-based cryptosystems, lattice reductionalgorithms are analyzed to evaluate the security of this scheme. Furthermore, the new scheme remains the advantage of high efficiency of original NTRU.展开更多
In this paper, we propose a novel block cryptographic scheme based on a spatiotemporal chaotic system and a chaotic neural network (CNN). The employed CNN comprises a 4-neuron layer called a chaotic neuron layer (...In this paper, we propose a novel block cryptographic scheme based on a spatiotemporal chaotic system and a chaotic neural network (CNN). The employed CNN comprises a 4-neuron layer called a chaotic neuron layer (CNL), where the spatiotemporal chaotic system participates in generating its weight matrix and other parameters. The spatiotemporal chaotic system used in our scheme is the typical coupled map lattice (CML), which can be easily implemented in parallel by hard- ware. A 160-bit-long binary sequence is used to generate the initial conditions of the CML. The decryption process is symmetric relative to the encryption process. Theoretical analysis and experimental results prove that the block cryptosys- tem is secure and practical, and suitable for image encryption.展开更多
The short secret key characteristic of elliptic curve cryptosystem (ECC) are integrated with the ( t, n ) threshold method to create a practical threshold group signature scheme characterized by simultaneous signi...The short secret key characteristic of elliptic curve cryptosystem (ECC) are integrated with the ( t, n ) threshold method to create a practical threshold group signature scheme characterized by simultaneous signing. The scheme not only meets the requirements of anonymity and traceability of group signature but also can withstand Tseng and Wang's conspiracy attack. It allows the group manager to add new members and delete old members according to actual application, while the system parameters have a little change. Cryptanalysis result shows that the scheme is efficient and secure.展开更多
The rapid transmission of multimedia information has been achieved mainly by recent advancements in the Internet’s speed and information technology.In spite of this,advancements in technology have resulted in breache...The rapid transmission of multimedia information has been achieved mainly by recent advancements in the Internet’s speed and information technology.In spite of this,advancements in technology have resulted in breaches of privacy and data security.When it comes to protecting private information in today’s Internet era,digital steganography is vital.Many academics are interested in digital video because it has a great capability for concealing important data.There have been a vast number of video steganography solutions developed lately to guard against the theft of confidential data.The visual imperceptibility,robustness,and embedding capacity of these approaches are all challenges that must be addressed.In this paper,a novel solution to reversible video steganography based on Discrete Wavelet Transform(DWT)and Quick Response(QR)codes is proposed to address these concerns.In order to increase the security level of the suggested method,an enhanced ElGamal cryptosystem has also been proposed.Prior to the embedding stage,the suggested method uses the modified ElGamal algorithm to encrypt secret QR codes.Concurrently,it applies two-dimensional DWT on the Y-component of each video frame resulting in Approximation(LL),Horizontal(LH),Vertical(HL),and Diagonal(HH)sub-bands.Then,the encrypted Low(L),Medium(M),Quantile(Q),and High(H)QR codes are embedded into the HL sub-band,HHsub-band,U-component,and V-component of video frames,respectively,using the Least Significant Bit(LSB)technique.As a consequence of extensive testing of the approach,it was shown to be very secure and highly invisible,as well as highly resistant to attacks from Salt&Pepper,Gaussian,Poisson,and Speckle noises,which has an average Structural Similarity Index(SSIM)of more than 0.91.Aside from visual imperceptibility,the suggested method exceeds current methods in terms of Peak Signal-to-Noise Ratio(PSNR)average of 52.143 dB,and embedding capacity 1 bpp.展开更多
This paper proposed a distributed key management approach by using the recently developed concepts of certificate-based cryptosystem and threshold secret sharing schemes. Without any assumption of prefixed trust relat...This paper proposed a distributed key management approach by using the recently developed concepts of certificate-based cryptosystem and threshold secret sharing schemes. Without any assumption of prefixed trust relationship between nodes, the ad hoc network works in a self-organizing way to provide the key generation and key management services using threshold secret sharing schemes, which effectively solves the problem of single point of failure. The proposed approach combines the best aspects of identity-based key management approaches (implicit certification) and traditional public key infrastructure approaches (no key escrow).展开更多
We propose a new fractional two-dimensional triangle function combination discrete chaotic map(2D-TFCDM)with the discrete fractional difference.Moreover,the chaos behaviors of the proposed map are observed and the bif...We propose a new fractional two-dimensional triangle function combination discrete chaotic map(2D-TFCDM)with the discrete fractional difference.Moreover,the chaos behaviors of the proposed map are observed and the bifurcation diagrams,the largest Lyapunov exponent plot,and the phase portraits are derived,respectively.Finally,with the secret keys generated by Menezes-Vanstone elliptic curve cryptosystem,we apply the discrete fractional map into color image encryption.After that,the image encryption algorithm is analyzed in four aspects and the result indicates that the proposed algorithm is more superior than the other algorithms.展开更多
The paper review the public-key cryptosystems based on the error correcting codes such as Goppa code, BCH code, RS code, rank distance code, algebraic geometric code as well as LDPC code, and made the comparative anal...The paper review the public-key cryptosystems based on the error correcting codes such as Goppa code, BCH code, RS code, rank distance code, algebraic geometric code as well as LDPC code, and made the comparative analyses of the merits and drawbacks of them. The cryptosystem based on Goppa code has high security, but can be achieved poor. The cryptosystems based on other error correcting codes have higher performance than Goppa code. But there are still some disadvantages to solve. At last, the paper produce an assumption of the Niederreiter cascade combination cryptosystem based on double public-keys under complex circumstances, which has higher performance and security than the traditional cryptosystems.展开更多
基金The National Natural Science Foundation of China(No.60473028)the Natural Science Foundation of Zhengzhou University of Light Industry(No.2006XXJ18)the Doctor Foundation of Zhengzhou University of Light Industry(No.20080014)
文摘To realize delegation between different users in a mixed cryptosystem,a proxy signature scheme for ID-based original signers and certificated-based proxy signers(PSS-ID-CER)is defined.Using the bilinear properties of the pairings and the characters of key generations of certificate-based cryptosystems and ID-based cryptosystems,a construction for such a scheme is also presented.To prove the security of the proposed scheme,a general security model for this scheme under adaptive chosen-PKG,chosen-ID,chosen-delegation,chosen-ProxySigner-public-key,chosen-proxy-key and chosen-message attack is defined.The proposed scheme is provably secure under the random oracle model and the hardness assumption of computational Diffie-Hellman problem.
文摘The basic idea behind an ID-based cryptosystem is that end user's public key can be determined by his identity information.Comparing with the traditional certificate-based cryptography,identity-based cryptography can eliminate much of the overhead associated with the deployment and management of certificate.However,exposure of private keys can be the most devastating attack on a public key based cryptosystem since such that all security guarantees are lost.In this paper,an ID-based authenticated key agreement protocol was presented.For solving the problem of key exposure of the basic scheme,the technique of key insulation was applied and a key insulated version is developed.
基金Supported bythe National Key Basic Research andDevelopment Program (973 Program G1999035804),the NationalNatural Science Foundation of China (90204015 ,60473021) and theElitist Youth Foundation of Henan Province (021201400)
文摘ID-based public key cryptosystem can be a good alternative for certifieate-based public key setting. This paper provides an efficient ID-based proxy multi signature scheme from pairings. In the random oracle model, we prove that our new scheme is secure against existential delegation forgery with the assumption that Hess's scheme-1 is existential unforgeable, and that our new scheme is secure against existential proxy multi-signature forgery under the hardness assumption of the computational Diffie-Hellman problem.
基金Supported by the Applied Basic and Advanced Technology Research Programs of Tianjin(15JCYBJC15900)the National Natural Science Foundation of China(51378350)
文摘Cloud storage service reduces the burden of data users by storing users' data files in the cloud. But, the files might be modified in the cloud. So, data users hope to check data files integrity periodically. In a public auditing protocol, there is a trusted auditor who has certain ability to help users to check the integrity of data files. With the advantages of no public key management and verification, researchers focus on public auditing protocol in ID-based cryptography recently. However, some existing protocols are vulnerable to forgery attack. In this paper, based on ID-based signature technology, by strengthening information authentication and the computing power of the auditor, we propose an ID-based public auditing protocol for cloud data integrity checking. We also prove that the proposed protocol is secure in the random oracle model under the assumption that the Diffie-Hellman problem is hard. Furthermore, we compare the proposed protocol with other two ID-based auditing protocols in security features, communication efficiency and computation cost. The comparisons show that the proposed protocol satisfies more security features with lower computation cost.
基金National Natural Science Foundation of Chi-na for Distinguished Young Scholars (No.60225007)National Research Fund for theDoctoral Program of Higher Education ofChina (No.20020248024)Grant-in-Aid forScientific Research(C) (No.14540100)
文摘Identity-based proxy signature enables an entity to delegate its signing rights to another entity in identity-based cryptosystem settings. However, few existing scheme has been proved secure in a formalized model, or acquired optimized performance. To achieve the goals of both proven security and high efficiency, this paper proposed an efficient identity-based proxy signature scheme. The scheme is constructed from bilinear pairing and proved secure in the random oracle model, using the oracle replay attack technique introduced by Pointehval and Stern. The analysis shows that the scheme needs less computation costs and has a shorter signature than the other schemes.
基金Supported by the National High Technology Research and Development Program of China (863 Program) (2006AA01Z442)the Spanish Government through Projects (E-AEGIS) (TSI2007- 65406-C03-01)+1 种基金(ARES) CONSOLIDER INGENIO 2010 (CSD2007- 00004)the Government of Catalonia (2005 SGR 00446)
文摘In existing software registration schemes, the privacy of users is not taken into account and may be in the risks of abuses. In this paper, we proposed a novel software registration system which can greatly reduce unauthorized use of software while keeping the privacy of users. To the best of our knowledge, this is the first system that the privacy of users is guaranteed in software registration. Our system enjoys a modular design and can be implemented by any secure ID-based partially blind signature scheme. Furthermore, the proposal allows flexible registration information definition. This feature makes our scheme flexible and practical for more software registration applications.
基金Supported by the National Natural Science Foundation of China (60473021) and the Science Foundation of Henan Province (0511010900)
文摘In the last couple of years, D-based cryptography has got fruitful achievements. Proxy multi-signature allows a designated person, called a proxy signer, to sign on behalf of two or more original signers. In this paper, we present a general security model for ID-based proxy multi-signature (ID-PMS) schemes. Then, we show how to construct a secure ID-PMS scheme from a secure ID-based signature scheme, and prove that the security of the construction can be reduced to the security of the original ID-based signature scheme.
文摘Two ID-based authenticated group key agreement schemes, proposed by Choi et al and Du et al, are insecure against an impersonation attack and th ey only discussed the static group. This paper proposed a variant of BD protocol , which is fully authenticated by a proven-secure ID-based signature scheme. T he protocol can res ist the impersonation attack, and other security attributes are also satisfied. Compared with Choi et al and Du et al schemes, the proposed one is mor e efficient and applicable for dynamic groups.
文摘Peer-to-peer computing has recently started to gain significant acceptance, since it can greatly increase the performance and reliability of overall system. However, the security issue is still a major gating factor for its full adoption. In order to guarantee the security of data exchanged between two peers in Peer-to-Peer system, this paper comes up with an ID-based authenticated key agreement from bilinear pairings and uses BAN logic to prove the protocol’s security. Compared with other existing protocols, the proposed protocol seems more secure and efficient, since it adopts the static shared Diffie-Hellman key.
文摘Key escrow is an inherent disadvantage for traditional ID-based cryptosystem, i.e., the dishonest private key generator (PKG) can forge the signature of any user, meanwhile, the user can deny the signature actually signed by him/herself. To avoid the keyescrow problem, an ID-based signature scheme was presented without trusted PKG. The exact proof of security was presented to demonstrate that our scheme is secure against existential forgery on adaptively chosen message and ID attacks assuming the complexity of computational Diffie-Hellman (CDH) problem. Compared with other signature schemes, the proposed scheme is more efficient.
文摘This paper presents a high-security medical image encryption method that leverages a novel and robust sine-cosine map.The map demonstrates remarkable chaotic dynamics over a wide range of parameters.We employ nonlinear analytical tools to thoroughly investigate the dynamics of the chaotic map,which allows us to select optimal parameter configurations for the encryption process.Our findings indicate that the proposed sine-cosine map is capable of generating a rich variety of chaotic attractors,an essential characteristic for effective encryption.The encryption technique is based on bit-plane decomposition,wherein a plain image is divided into distinct bit planes.These planes are organized into two matrices:one containing the most significant bit planes and the other housing the least significant ones.The subsequent phases of chaotic confusion and diffusion utilize these matrices to enhance security.An auxiliary matrix is then generated,comprising the combined bit planes that yield the final encrypted image.Experimental results demonstrate that our proposed technique achieves a commendable level of security for safeguarding sensitive patient information in medical images.As a result,image quality is evaluated using the Structural Similarity Index(SSIM),yielding values close to zero for encrypted images and approaching one for decrypted images.Additionally,the entropy values of the encrypted images are near 8,with a Number of Pixel Change Rate(NPCR)and Unified Average Change Intensity(UACI)exceeding 99.50%and 33%,respectively.Furthermore,quantitative assessments of occlusion attacks,along with comparisons to leading algorithms,validate the integrity and efficacy of our medical image encryption approach.
基金supported by Comunidad de Madrid within the framework of the Multiannual Agreement with Universidad Politecnica de Madrid to encourage research by young doctors(PRINCE).
文摘The Industry 4.0 revolution is characterized by distributed infrastructures where data must be continuously communicated between hardware nodes and cloud servers.Specific lightweight cryptosystems are needed to protect those links,as the hardware node tends to be resource-constrained.Then Pseudo Random Number Generators are employed to produce random keys,whose final behavior depends on the initial seed.To guarantee good mathematical behavior,most key generators need an unpredictable voltage signal as input.However,physical signals evolve slowly and have a significant autocorrelation,so they do not have enough entropy to support highrandomness seeds.Then,electronic mechanisms to generate those high-entropy signals artificially are required.This paper proposes a robust hyperchaotic circuit to obtain such unpredictable electric signals.The circuit is based on a hyperchaotic dynamic system,showing a large catalog of structures,four different secret parameters,and producing four high entropy voltage signals.Synchronization schemes for the correct secret key calculation and distribution among all remote communicating modules are also analyzed and discussed.Security risks and intruder and attacker models for the proposed solution are explored,too.An experimental validation based on circuit simulations and a real hardware implementation is provided.The results show that the random properties of PRNG improved by up to 11%when seeds were calculated through the proposed circuit.
基金the National Natural Science Foundation of China(Nos.61202023,60903189 and 61133014)
文摘This study deals with the dynamic property of threshold cryptosystem. A dynamic threshold cryptosystem allows the sender to choose the authorized decryption group and the threshold value for each message dynamically. We first introduce an identity based dynamic threshold cryptosystem, and then use the CanettiHalevi-Katz(CHK) transformation to transform it into a fully secure system in the traditional public key setting.Finally, the elegant dual system encryption technique is applied to constructing a fully secure dynamic threshold cryptosystem with adaptive security.
文摘An enhaned NTRU cryptosystem eliminating decryption failures is proposed without using padding schemes and can resist the oracle model andchosen-ciphertext attacks. Because lattice reduction is the main threat to lattice-based cryptosystems, lattice reductionalgorithms are analyzed to evaluate the security of this scheme. Furthermore, the new scheme remains the advantage of high efficiency of original NTRU.
基金Project supported by the National Natural Science Foundation of China (Grant Nos. 61173183, 60973152, and 60573172)the Doctoral Program Foundation of Institution of Higher Education of China (Grant No. 20070141014)+2 种基金the Program for Excellent Talents in Universities of Liaoning Province, China (Grant No. LR2012003)the Natural Science Foundation of Liaoning Province, China (Grant No. 20082165)the Fundamental Research Funds for the Central Universities of China (Grant No. DUT12JB06)
文摘In this paper, we propose a novel block cryptographic scheme based on a spatiotemporal chaotic system and a chaotic neural network (CNN). The employed CNN comprises a 4-neuron layer called a chaotic neuron layer (CNL), where the spatiotemporal chaotic system participates in generating its weight matrix and other parameters. The spatiotemporal chaotic system used in our scheme is the typical coupled map lattice (CML), which can be easily implemented in parallel by hard- ware. A 160-bit-long binary sequence is used to generate the initial conditions of the CML. The decryption process is symmetric relative to the encryption process. Theoretical analysis and experimental results prove that the block cryptosys- tem is secure and practical, and suitable for image encryption.
基金The National Natural Science Foundation of China (No60403027)
文摘The short secret key characteristic of elliptic curve cryptosystem (ECC) are integrated with the ( t, n ) threshold method to create a practical threshold group signature scheme characterized by simultaneous signing. The scheme not only meets the requirements of anonymity and traceability of group signature but also can withstand Tseng and Wang's conspiracy attack. It allows the group manager to add new members and delete old members according to actual application, while the system parameters have a little change. Cryptanalysis result shows that the scheme is efficient and secure.
文摘The rapid transmission of multimedia information has been achieved mainly by recent advancements in the Internet’s speed and information technology.In spite of this,advancements in technology have resulted in breaches of privacy and data security.When it comes to protecting private information in today’s Internet era,digital steganography is vital.Many academics are interested in digital video because it has a great capability for concealing important data.There have been a vast number of video steganography solutions developed lately to guard against the theft of confidential data.The visual imperceptibility,robustness,and embedding capacity of these approaches are all challenges that must be addressed.In this paper,a novel solution to reversible video steganography based on Discrete Wavelet Transform(DWT)and Quick Response(QR)codes is proposed to address these concerns.In order to increase the security level of the suggested method,an enhanced ElGamal cryptosystem has also been proposed.Prior to the embedding stage,the suggested method uses the modified ElGamal algorithm to encrypt secret QR codes.Concurrently,it applies two-dimensional DWT on the Y-component of each video frame resulting in Approximation(LL),Horizontal(LH),Vertical(HL),and Diagonal(HH)sub-bands.Then,the encrypted Low(L),Medium(M),Quantile(Q),and High(H)QR codes are embedded into the HL sub-band,HHsub-band,U-component,and V-component of video frames,respectively,using the Least Significant Bit(LSB)technique.As a consequence of extensive testing of the approach,it was shown to be very secure and highly invisible,as well as highly resistant to attacks from Salt&Pepper,Gaussian,Poisson,and Speckle noises,which has an average Structural Similarity Index(SSIM)of more than 0.91.Aside from visual imperceptibility,the suggested method exceeds current methods in terms of Peak Signal-to-Noise Ratio(PSNR)average of 52.143 dB,and embedding capacity 1 bpp.
文摘This paper proposed a distributed key management approach by using the recently developed concepts of certificate-based cryptosystem and threshold secret sharing schemes. Without any assumption of prefixed trust relationship between nodes, the ad hoc network works in a self-organizing way to provide the key generation and key management services using threshold secret sharing schemes, which effectively solves the problem of single point of failure. The proposed approach combines the best aspects of identity-based key management approaches (implicit certification) and traditional public key infrastructure approaches (no key escrow).
基金Project supported by the National Natural Science Foundation of China(Grant Nos.61072147 and 11271008)
文摘We propose a new fractional two-dimensional triangle function combination discrete chaotic map(2D-TFCDM)with the discrete fractional difference.Moreover,the chaos behaviors of the proposed map are observed and the bifurcation diagrams,the largest Lyapunov exponent plot,and the phase portraits are derived,respectively.Finally,with the secret keys generated by Menezes-Vanstone elliptic curve cryptosystem,we apply the discrete fractional map into color image encryption.After that,the image encryption algorithm is analyzed in four aspects and the result indicates that the proposed algorithm is more superior than the other algorithms.
基金Supported by the Postgraduate Project of Military Science of PLA(2013JY431)55th Batch of China Postdoctoral Second-Class on Fund Projects(2014M552656)
文摘The paper review the public-key cryptosystems based on the error correcting codes such as Goppa code, BCH code, RS code, rank distance code, algebraic geometric code as well as LDPC code, and made the comparative analyses of the merits and drawbacks of them. The cryptosystem based on Goppa code has high security, but can be achieved poor. The cryptosystems based on other error correcting codes have higher performance than Goppa code. But there are still some disadvantages to solve. At last, the paper produce an assumption of the Niederreiter cascade combination cryptosystem based on double public-keys under complex circumstances, which has higher performance and security than the traditional cryptosystems.