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
Based on the characteristic of key-insulated public-key cryptosystem, wepropose a distributed landora session keys distribution protocol without a key distribution center.The session key is generated by different user...Based on the characteristic of key-insulated public-key cryptosystem, wepropose a distributed landora session keys distribution protocol without a key distribution center.The session key is generated by different user and only used one time. So thekey is one-time key. Inaddition, the user who generates the next one-time key, is random selected by the current sessionkey. In the protocol of this paper, the characteristic of time in the key-insulated public-key, adistributed protocol, translates into the characteristic of spaee which every point has differentsecret key in the different period. At the same time, the system is fit for key management in AdHoe, and is a new scheme of key management in Ad Hoc.展开更多
A joint signature,encryption and error correction public-key cryptosystem is pre-sented based on an NP-completeness problem-the decoding problem of general linear codes inalgebraic coding theory,
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.
The most popular present-day public-key cryptosystems are RSA and ElGamal cryptosystems. Some practical algebraic generalization of the ElGamal cryptosystem is considered-basic modular matrix cryptosystem (BMMC) over ...The most popular present-day public-key cryptosystems are RSA and ElGamal cryptosystems. Some practical algebraic generalization of the ElGamal cryptosystem is considered-basic modular matrix cryptosystem (BMMC) over the modular matrix ring M2(Zn). An example of computation for an artificially small number n is presented. Some possible attacks on the cryptosystem and mathematical problems, the solution of which are necessary for implementing these attacks, are studied. For a small number n, computational time for compromising some present-day public-key cryptosystems such as RSA, ElGamal, and Rabin, is compared with the corresponding time for the ВММС. Finally, some open mathematical and computational problems are formulated.展开更多
This paper describes and compares a variety of algorithms for secure transmission of information via open communication channels based on the discrete logarithm problem that do not require search for a generator (prim...This paper describes and compares a variety of algorithms for secure transmission of information via open communication channels based on the discrete logarithm problem that do not require search for a generator (primitive element). Modifications that simplify the cryptosystem are proposed, and, as a result, accelerate its performance. It is shown that hiding information via exponentiation is more efficient than other seemingly simpler protocols. Some of these protocols also provide digital signature/sender identification. Numeric illustrations are provided.展开更多
Properties of third-order recurrence sequences were investigated and a new variant of the GH public-key cryptosystem,which was further improved to be a probabil-istic public-key cryptosystem,was proposed.Then security...Properties of third-order recurrence sequences were investigated and a new variant of the GH public-key cryptosystem,which was further improved to be a probabil-istic public-key cryptosystem,was proposed.Then security analysis of the proposed scheme was provided and it was proved that the one-wayness of the proposed scheme is equivalent to partial discrete logarithm and its semantic se-curity is equivalent to decisional Diffie-Hellman problem in ring extension.Finally,efficiency analysis of the proposed scheme was provided,and that these two encryption schemes need to transfer 2log N and 4log N bits data re-spectively.展开更多
Okamoto public-key cryptosystem (abbr. OPKC)has drawn considerable attention for its convenience and rapidity of encryption and decryption. K. Koyama, A.Shamir, B. Vallee and others already analyzed it and presented s...Okamoto public-key cryptosystem (abbr. OPKC)has drawn considerable attention for its convenience and rapidity of encryption and decryption. K. Koyama, A.Shamir, B. Vallee and others already analyzed it and presented some attacks. This report gives OPKC an elementary attack, which can not only break completely both the systems of OPKC but also be used to attack other public-key cryptosystems similar to OPKC, such as展开更多
During the last two decades, there has been intensive and fast development in Multivariate Public Key Cryptography （MPKC）, which is considered to be an important candidate for post-quantum cryptography. However, it ...During the last two decades, there has been intensive and fast development in Multivariate Public Key Cryptography （MPKC）, which is considered to be an important candidate for post-quantum cryptography. However, it is universally regarded as a difficult task, as in the Knapsack cryptosystems, to design a secure MPKC scheme （especially an encryption scheme） employing the existing trapdoor construction. In this paper, we propose a new key-exchange scheme and an MPKC scheme based on the Morphism of Polynomials （MP） problem. The security of the proposed schemes is provably reducible to the conjectured intractability of a new difficult problem, namely the Decisional Multivariate Diffie-Hellman （DMDH） problem derived from the MP problem. The proposed key agreement is one of several non-number-theory-based protocols, and is a candidate for use in the post-quantum era. More importantly, by slightly modifying the protocol, we offer an original approach to designing a secure MPKC scheme. Furthermore, the proposed encryption scheme achieves a good tradeoff between security and efficiency, and seems competitive with traditional MPKC schemes.展开更多
The present paper proposes a secure design of the energy-efficient multi-modular exponential techniques that use store and reward method and store and forward method.Computation of the multi-modular exponentiation can...The present paper proposes a secure design of the energy-efficient multi-modular exponential techniques that use store and reward method and store and forward method.Computation of the multi-modular exponentiation can be performed by three novel algorithms:store and reward,store and forward 1-bit(SFW1),and store and forward 2-bit(SFW2).Hardware realizations of the proposed algorithms are analyzed in terms of throughput and energy.The experimental results show the proposed algorithms SFW1 and SFW2 increase the throughput by orders of 3.98% and 4.82%,reducing the power by 5.32% and 6.15% and saving the energy in the order of 3.95% and 4.75%,respectively.The proposed techniques can prevent possible side-channel attacks and timing attacks as a consequence of an inbuilt confusion mechanism.Xilinx Vivado-21 on Virtex-7 evaluation board and integrated computer application for recognizing user services(ICARUS)Verilog simulation and synthesis tools are used for field programmable gate array(FPGA)for hardware realization.The hardware compatibility of proposed algorithms has also been checked using Cadence for application specific integrated circuit(ASIC).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
Tag key encapsulation mechanism （Tag-KEM）/data encapsulation mechanism （DEM） is a hybrid framework proposed in 2005. Tag-t（EM is one of its parts by using public-key encryption （PKE） technique to encapsulate a ...Tag key encapsulation mechanism （Tag-KEM）/data encapsulation mechanism （DEM） is a hybrid framework proposed in 2005. Tag-t（EM is one of its parts by using public-key encryption （PKE） technique to encapsulate a symmetric key. In hybrid encryptions, the long-raessage PKE is not desired due to its slow operation. A general method is presented for constructing Tag-KEM schemes with short-message PKEs. The chosen ciphertext security is proved in the random oracle model. In the method, the treatment of the tag part brings no additional ciphertext redundancy. Among all the methods for constructing Tag-KEM, the method is the first one without any validity checking on the tag part, thus showing that the Tag-KEM/DEM framework is superior to KEM＋DEM one.展开更多
Advances in quantum computers pose potential threats to the currently used public-key cryptographic algorithms such as RSA and ECC.As a promising candidate against attackers equipped with quantum computational power,M...Advances in quantum computers pose potential threats to the currently used public-key cryptographic algorithms such as RSA and ECC.As a promising candidate against attackers equipped with quantum computational power,Multivariate Public-Key Cryptosystems(MPKCs)has attracted increasing attention in recently years.Unfortunately,the existing MPKCs can only be used as multivariate signature schemes,and the way to construct an efficient MPKC enabling secure encryption remains unknown.By employing the basic MQ-trapdoors,this paper proposes a novel multivariate encryption scheme by combining MPKCs and code-based public-key encryption schemes.Our new construction gives a positive response to the challenges in multivariate public key cryptography.Thorough analysis shows that our scheme is secure and efficient,and its private key size is about 10 times smaller than that of McEliece-type cryptosystems.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
RSA public key crypto system is a relatively safe technology, which is widely used in today’s secure electronic communication. In this paper, a new implementation method to optimize a 1 024 bit RSA processor was pres...RSA public key crypto system is a relatively safe technology, which is widely used in today’s secure electronic communication. In this paper, a new implementation method to optimize a 1 024 bit RSA processor was presented. Basically, a fast modular multiplication architecture based on Montgomery’s algorithm was proposed. Modular exponentiation algorithm scans encryption from right to left, so two modular multiplications can be processed parallel. The new architecture is also fit for an effective I/O interface. The time to calculate a modular exponentiation is about n 2 clock cycles. The proposed architecture has a data rate of 93.7 kb/s for 1 024 bit work with a 100 MHz clock.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
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.
文摘Based on the characteristic of key-insulated public-key cryptosystem, wepropose a distributed landora session keys distribution protocol without a key distribution center.The session key is generated by different user and only used one time. So thekey is one-time key. Inaddition, the user who generates the next one-time key, is random selected by the current sessionkey. In the protocol of this paper, the characteristic of time in the key-insulated public-key, adistributed protocol, translates into the characteristic of spaee which every point has differentsecret key in the different period. At the same time, the system is fit for key management in AdHoe, and is a new scheme of key management in Ad Hoc.
基金Subject supported by the National Natural Science Fund of China
文摘A joint signature,encryption and error correction public-key cryptosystem is pre-sented based on an NP-completeness problem-the decoding problem of general linear codes inalgebraic coding theory,
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.
文摘The most popular present-day public-key cryptosystems are RSA and ElGamal cryptosystems. Some practical algebraic generalization of the ElGamal cryptosystem is considered-basic modular matrix cryptosystem (BMMC) over the modular matrix ring M2(Zn). An example of computation for an artificially small number n is presented. Some possible attacks on the cryptosystem and mathematical problems, the solution of which are necessary for implementing these attacks, are studied. For a small number n, computational time for compromising some present-day public-key cryptosystems such as RSA, ElGamal, and Rabin, is compared with the corresponding time for the ВММС. Finally, some open mathematical and computational problems are formulated.
文摘This paper describes and compares a variety of algorithms for secure transmission of information via open communication channels based on the discrete logarithm problem that do not require search for a generator (primitive element). Modifications that simplify the cryptosystem are proposed, and, as a result, accelerate its performance. It is shown that hiding information via exponentiation is more efficient than other seemingly simpler protocols. Some of these protocols also provide digital signature/sender identification. Numeric illustrations are provided.
基金supported by the National Natural Science Foundation of China(No.90412011)the Hi-Tech Research and Development Program of China(No.2002AA143021)。
文摘Properties of third-order recurrence sequences were investigated and a new variant of the GH public-key cryptosystem,which was further improved to be a probabil-istic public-key cryptosystem,was proposed.Then security analysis of the proposed scheme was provided and it was proved that the one-wayness of the proposed scheme is equivalent to partial discrete logarithm and its semantic se-curity is equivalent to decisional Diffie-Hellman problem in ring extension.Finally,efficiency analysis of the proposed scheme was provided,and that these two encryption schemes need to transfer 2log N and 4log N bits data re-spectively.
基金Project supported by the National Natural Science Foundation of China.
文摘Okamoto public-key cryptosystem (abbr. OPKC)has drawn considerable attention for its convenience and rapidity of encryption and decryption. K. Koyama, A.Shamir, B. Vallee and others already analyzed it and presented some attacks. This report gives OPKC an elementary attack, which can not only break completely both the systems of OPKC but also be used to attack other public-key cryptosystems similar to OPKC, such as
基金supported by the National Natural Science Foundation of China (Nos.61303212,61303024,61170080,61501333,61303024,and 61332019)the Foundation of Science and Technology on Information Assurance Laboratory (No.KJ-14-002)
文摘During the last two decades, there has been intensive and fast development in Multivariate Public Key Cryptography （MPKC）, which is considered to be an important candidate for post-quantum cryptography. However, it is universally regarded as a difficult task, as in the Knapsack cryptosystems, to design a secure MPKC scheme （especially an encryption scheme） employing the existing trapdoor construction. In this paper, we propose a new key-exchange scheme and an MPKC scheme based on the Morphism of Polynomials （MP） problem. The security of the proposed schemes is provably reducible to the conjectured intractability of a new difficult problem, namely the Decisional Multivariate Diffie-Hellman （DMDH） problem derived from the MP problem. The proposed key agreement is one of several non-number-theory-based protocols, and is a candidate for use in the post-quantum era. More importantly, by slightly modifying the protocol, we offer an original approach to designing a secure MPKC scheme. Furthermore, the proposed encryption scheme achieves a good tradeoff between security and efficiency, and seems competitive with traditional MPKC schemes.
基金the DST of India for sponsoring this project under Interdisciplinary Cyber Physical Systems(ICPS)Division individual category with reference number:DST/ICPS/CPSIndividual/2018/895(G)(T-895).
文摘The present paper proposes a secure design of the energy-efficient multi-modular exponential techniques that use store and reward method and store and forward method.Computation of the multi-modular exponentiation can be performed by three novel algorithms:store and reward,store and forward 1-bit(SFW1),and store and forward 2-bit(SFW2).Hardware realizations of the proposed algorithms are analyzed in terms of throughput and energy.The experimental results show the proposed algorithms SFW1 and SFW2 increase the throughput by orders of 3.98% and 4.82%,reducing the power by 5.32% and 6.15% and saving the energy in the order of 3.95% and 4.75%,respectively.The proposed techniques can prevent possible side-channel attacks and timing attacks as a consequence of an inbuilt confusion mechanism.Xilinx Vivado-21 on Virtex-7 evaluation board and integrated computer application for recognizing user services(ICARUS)Verilog simulation and synthesis tools are used for field programmable gate array(FPGA)for hardware realization.The hardware compatibility of proposed algorithms has also been checked using Cadence for application specific integrated circuit(ASIC).
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Supported by the National Natural Science Foundation of China(60603010,60970120)~~
文摘Tag key encapsulation mechanism （Tag-KEM）/data encapsulation mechanism （DEM） is a hybrid framework proposed in 2005. Tag-t（EM is one of its parts by using public-key encryption （PKE） technique to encapsulate a symmetric key. In hybrid encryptions, the long-raessage PKE is not desired due to its slow operation. A general method is presented for constructing Tag-KEM schemes with short-message PKEs. The chosen ciphertext security is proved in the random oracle model. In the method, the treatment of the tag part brings no additional ciphertext redundancy. Among all the methods for constructing Tag-KEM, the method is the first one without any validity checking on the tag part, thus showing that the Tag-KEM/DEM framework is superior to KEM＋DEM one.
基金National Natural Science Foundation of China under Grant No. 60970115,60970116,61003267, 61003268,61003214the Major Research Plan of the National Natural Science Foundation of China under Grant No. 91018008
文摘Advances in quantum computers pose potential threats to the currently used public-key cryptographic algorithms such as RSA and ECC.As a promising candidate against attackers equipped with quantum computational power,Multivariate Public-Key Cryptosystems(MPKCs)has attracted increasing attention in recently years.Unfortunately,the existing MPKCs can only be used as multivariate signature schemes,and the way to construct an efficient MPKC enabling secure encryption remains unknown.By employing the basic MQ-trapdoors,this paper proposes a novel multivariate encryption scheme by combining MPKCs and code-based public-key encryption schemes.Our new construction gives a positive response to the challenges in multivariate public key cryptography.Thorough analysis shows that our scheme is secure and efficient,and its private key size is about 10 times smaller than that of McEliece-type cryptosystems.
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NSF of U nited States under Contract 5 978East Asia and Pacific Program(960 2 485 )
文摘RSA public key crypto system is a relatively safe technology, which is widely used in today’s secure electronic communication. In this paper, a new implementation method to optimize a 1 024 bit RSA processor was presented. Basically, a fast modular multiplication architecture based on Montgomery’s algorithm was proposed. Modular exponentiation algorithm scans encryption from right to left, so two modular multiplications can be processed parallel. The new architecture is also fit for an effective I/O interface. The time to calculate a modular exponentiation is about n 2 clock cycles. The proposed architecture has a data rate of 93.7 kb/s for 1 024 bit work with a 100 MHz clock.
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.
