With the rapid development of information technology,data security issues have received increasing attention.Data encryption and decryption technology,as a key means of ensuring data security,plays an important role i...With the rapid development of information technology,data security issues have received increasing attention.Data encryption and decryption technology,as a key means of ensuring data security,plays an important role in multiple fields such as communication security,data storage,and data recovery.This article explores the fundamental principles and interrelationships of data encryption and decryption,examines the strengths,weaknesses,and applicability of symmetric,asymmetric,and hybrid encryption algorithms,and introduces key application scenarios for data encryption and decryption technology.It examines the challenges and corresponding countermeasures related to encryption algorithm security,key management,and encryption-decryption performance.Finally,it analyzes the development trends and future prospects of data encryption and decryption technology.This article provides a systematic understanding of data encryption and decryption techniques,which has good reference value for software designers.展开更多
Dear Editor,This letter deals with the distributed recursive set-membership filtering(DRSMF)issue for state-saturated systems under encryption-decryption mechanism.To guarantee the data security,the encryption-decrypt...Dear Editor,This letter deals with the distributed recursive set-membership filtering(DRSMF)issue for state-saturated systems under encryption-decryption mechanism.To guarantee the data security,the encryption-decryption mechanism is considered in the signal transmission process.Specifically,a novel DRSMF scheme is developed such that,for both state saturation and encryption-decryption mechanism,the filtering error(FE)is limited to the ellipsoid domain.Then,the filtering error constraint matrix(FECM)is computed and a desirable filter gain is derived by minimizing the FECM.Besides,the bound-edness evaluation of the FECM is provided.展开更多
Luminescent nanoclusters(NCs)have attracted much attention because of their superior photophysical properties;however,the design of dynamic NCs with reversible structural change is highly challenging.Herein,we synthes...Luminescent nanoclusters(NCs)have attracted much attention because of their superior photophysical properties;however,the design of dynamic NCs with reversible structural change is highly challenging.Herein,we synthesize a kind of dynamic luminescent NCs through Schiff base crosslinking between triethylenetetramine(TETA)and tannic acid at room temperature.The proposed NCs have an excitation-independent blue emission,and the maximum emission is available at about 458 nm with two excitation centers.Furthermore,the crosslinking degree of the NCs can be effectively adjusted by TETA and their formation is a kineticcontrol process.Most importantly,the proposed NCs show a property of pHcontrolled reversible depolymerization and polymerization,accompanied by a cyclic“on-off-on”photoswitching,which is directly attributed to pH-stimulated reversible C=N bond cleavage and re-formation.Because of the reversible structure change properties,the dynamic NCs have been well used in reversible information encryption.This new finding provides not only us with a powerful strategy to study the structure–properties relationship of luminescent NCs but also a design idea for constructing smart optical nanomaterials.展开更多
Black wings of butterfly Ornithoptera goliath and infrared-band radiative cooling function of Rapala dioetas butterfly wings are associated with black pigment(e.g.,melanin)and unique hierarchical micro/nanostructures,...Black wings of butterfly Ornithoptera goliath and infrared-band radiative cooling function of Rapala dioetas butterfly wings are associated with black pigment(e.g.,melanin)and unique hierarchical micro/nanostructures,greatly stimulating biomimetic fabrication of functional photonic structures but mainly targeted to one prototype.Targeted at two-prototype integrated biomimetic fabrication from fully compositional/structural/functional aspects,femtosecond(fs)laser subtractive/additive-integrated hierarchical micro/nano-manufacturing technique is proposed in this work.This technique can one-step transfer refractory metals(e.g.,W,Mo,Nb,Ta)into black non-stoichiometric oxide nanomaterials with abundant oxygen vacancies and simultaneously enable the realization of in situ quasi-controllable micro/nanoscale hierarchical aggregation and assembly,all displaying black color but with tunable infrared emission.Adjusting the scan interval for biomimetic manufacturing can tailor the structural oxidation degree,the emission in the long-wave infrared(LWIR)band while keeping the blackness of hierarchical aggregates,and the confined height between the covering quartz plate and the ablated sample.The blackening efficiency of this technique can reach∼11.25 cm^(2)·min^(−1),opening opportunities for high-throughput optical/thermal applications.Selectively patterned Chinese characters,Arabic numbers,and English letters are easily fabricable,which are intrinsically invisible-infrared dual-band encrypted but decryptable via static/dynamic environment stimuli(e.g.,sample heating/cooling,introducing external hot/cold sources including human hands).The self-evolution from‘orderless’structuring to‘ordered’functionalization is validated for the proposed fs laser subtractive/additive-integrated biomimetic manufacturing,specifically from the synthesis of diverse black nanomaterials and the seemingly disordered micro/nano-aggregates to the ordered optical/thermal regulation capacities for a delicate modulation of information encryption and decryption,unveiling a new concept for future exploration and extension.展开更多
Military image encryption plays a vital role in ensuring the secure transmission of sensitive visual information from unauthorized access.This paper proposes a new Tri-independent keying method for encrypting military...Military image encryption plays a vital role in ensuring the secure transmission of sensitive visual information from unauthorized access.This paper proposes a new Tri-independent keying method for encrypting military images.The proposed encryption method is based on multilevel security stages of pixel-level scrambling,bitlevel manipulation,and block-level shuffling operations.For having a vast key space,the input password is hashed by the Secure Hash Algorithm 256-bit(SHA-256)for generating independently deterministic keys used in the multilevel stages.A piecewise pixel-level scrambling function is introduced to perform a dual flipping process controlled with an adaptive key for obscuring the spatial relationships between the adjacent pixels.Adynamicmasking scheme is presented for conducting a bit-level manipulation based on distinct keys that change over image regions,providing completely different encryption results on identical regions.To handle the global correlation between large-scale patterns,a chaotic index-map system is employed for shuffling image regions randomly across the image domain based on a logistic map seeded with a private key.Experimental results on a dataset of military images show the effectiveness of the proposed encryption method in producing excellent quantitative and qualitative results.The proposed method obtains uniform histogram distributions,high entropy values around the ideal(≈8 bits),Number of Pixel Change Rate(NPCR)values above 99.5%,and low Peak Signal-to-Noise Ratio(PSNR)over all encrypted images.This validates the robustness of the proposed method against cryptanalytic attacks,verifying its ability to serve as a practical basis for secure image transmission in defense systems.展开更多
While biomaterials are endowed with sophisticated functions by the temporal dynamics and autonomy derived from non-equilibrium assemblies in biological systems,fabricating advanced materials counterparts with these fe...While biomaterials are endowed with sophisticated functions by the temporal dynamics and autonomy derived from non-equilibrium assemblies in biological systems,fabricating advanced materials counterparts with these features through kinetic control remains rare.Herein,we report a non-equilibrium hydrogel that exhibits autonomous time-dependent ultrabright fluorescence(quantum yield 0.90),achieved through the kinetically controlled incorporation of thermodynamic equilibrium host-vip complexes into a poly(2-hydroxyethyl methacrylate)(PHEMA)network.Transient complexes are programmed by coupling rapid assembly kinetics with the slow competitive binding of the polymer matrix.This kinetic mismatch converts a thermodynamic equilibrium supramolecular system into a non-equilibrium state,generating temporally dynamic fluorescence that cyclically shifts from yellow to green and self-reverts.The programmed temporal dynamics endow the hydrogel with high potential for information encryption applications.展开更多
Currently, there still lacks an efficient methodology to revoke user's ability to decrypt ciphertext in broadcast encryption with the uncertain number of ciphertext recipients. To solve this problem, here, we present...Currently, there still lacks an efficient methodology to revoke user's ability to decrypt ciphertext in broadcast encryption with the uncertain number of ciphertext recipients. To solve this problem, here, we present a dynamic broadcast encryption scheme with the following properties: First, the length of the ciphertext has a linear relationship with the number of revocable users, but it has no association with the total number of ciphertext recipients. Sec- ond, the scheme also works when users dynamically join. Espe- cially, compared with methods published up to date, our scheme is more efficient with a large number of ciphertext recipients. Third, the broadcaster can revoke user's ability to decrypt ciphertext if necessary. Fourth, the private key of users is composed of three elements in Elliptic curve group of prime order. Last, if q-Deci- sional Multi-Exponent Bilinear Diffie-Hellman assumption holds, our scheme is secure in the standard model when a polynomial time adversary selectively attacks it.展开更多
In this paper,a novel bit-level image encryption method based on dynamic grouping is proposed.In the proposed method,the plain-image is divided into several groups randomly,then permutation-diffusion process on bit le...In this paper,a novel bit-level image encryption method based on dynamic grouping is proposed.In the proposed method,the plain-image is divided into several groups randomly,then permutation-diffusion process on bit level is carried out.The keystream generated by logistic map is related to the plain-image,which confuses the relationship between the plain-image and the cipher-image.The computer simulation results of statistical analysis,information entropy analysis and sensitivity analysis show that the proposed encryption method is secure and reliable enough to be used for communication application.展开更多
Reconfigurable computing has grown to become an important and large field of research, it offers advantages over traditional hardware and software implementations of computational algorithms. The Advanced Encryption S...Reconfigurable computing has grown to become an important and large field of research, it offers advantages over traditional hardware and software implementations of computational algorithms. The Advanced Encryption Standard (AES) algorithm is widely applied in government department and commerce. This paper analyzed the AES algorithms with different cipher keys, adopted a novel key scheduler that generated the round key real-time, proposed a dynamically reconfigurable encryption system which supported the AES algorithm with different cipher keys, and designed the architecture of the reconfigurable system. The dynamically reconfigurable AES system had been realized on FPGA. The result proves that the reconfigurable AES system is flexible, lower cost and high security level.展开更多
In modern society,information is becoming increasingly interconnected through networks,and the rapid development of information technology has caused people to pay more attention to the encryption and the protection o...In modern society,information is becoming increasingly interconnected through networks,and the rapid development of information technology has caused people to pay more attention to the encryption and the protection of information.Image encryption technology is a key technology for ensuring the security performance of images.We extracted single channel RGB component images from a color image using MATLAB programs,encrypted and decrypted the color images by randomly disrupting rows,columns and regions of the image.Combined with histograms and the visual judgments of encryption images,it is shown that the information of the original image cannot be obtained from the encryption image easily.The results show that the color-image encryptions with the algorithm we used have good effect and fast operation speed.Thus this algorithm has certain practical value.展开更多
This paper analyzes the problems in image encryption and decryption based on chaos theory. This article introduces the application of the two-stage Logistic algorithm in image encryption and decryption, then by inform...This paper analyzes the problems in image encryption and decryption based on chaos theory. This article introduces the application of the two-stage Logistic algorithm in image encryption and decryption, then by information entropy analysis it is concluded that the security of this algorithm is higher compared with the original image;And a new image encryption and decryption algorithm based on the combination of two-stage Logistic mapping and <i>M</i> sequence is proposed. This new algorithm is very sensitive to keys;the key space is large and its security is higher than two-stage Logistic mapping of image encryption and decryption technology.展开更多
In this paper,we first propose a memristive chaotic system and implement it by circuit simulation.The chaotic dynamics and various attractors are analysed by using phase portrait,bifurcation diagram,and Lyapunov expon...In this paper,we first propose a memristive chaotic system and implement it by circuit simulation.The chaotic dynamics and various attractors are analysed by using phase portrait,bifurcation diagram,and Lyapunov exponents.In particular,the system has robust chaos in a wide parameter range and the initial value space,which is favourable to the security communication application.Consequently,we further explore its application in image encryption and present a new scheme.Before image processing,the external key is protected by the Grain-128a algorithm and the initial values of the memristive system are updated with the plain image.We not only perform random pixel extraction and masking with the chaotic cipher,but also use them as control parameters for Brownian motion to obtain the permutation matrix.In addition,multiplication on the finite field GF(2^(8))is added to further enhance the cryptography.Finally,the simulation results verify that the proposed image encryption scheme has better performance and higher security,which can effectively resist various attacks.展开更多
To share data securely with secure attribute revocation,anti-collusion,and dynamic user management in the 5G device-to-device(D2D)environment,a novel dynamic anti-collusion ciphertext policy attribute-based encryption...To share data securely with secure attribute revocation,anti-collusion,and dynamic user management in the 5G device-to-device(D2D)environment,a novel dynamic anti-collusion ciphertext policy attribute-based encryption(NDA-CP-ABE)scheme in the 5G D2D environment is proposed.On the basis of the ciphertext policy attribute-based encryption algorithm,fine-grained access control and secure attribute revocation are realized,and the confidentiality of data is guaranteed.A polynomial function is adopted in the ciphertext generation phase to realize dynamic user management.A random number is used to prevent a collusion attack among the legitimate user equipment(UE),revoked UE,and external network attackers.Finally,on the basis of the Diffie-Hellman problem,the NDA-CP-ABE scheme is formally proved,and the simulation performances are compared with those of similar schemes.The results show that data can be securely shared through a D2D channel with secure attribute revocation,anti-collusion,and dynamic user management.Moreover,compared with similar schemes,the NDA-CP-ABE scheme has higher efficiency in encryption,decryption,and storage.展开更多
A new dynamic encryption application in ad-hoc networks is proposed. The advantages of this method are its being able to use the previous ciphertext as a seed of a new encryption process, rendering the encryption proc...A new dynamic encryption application in ad-hoc networks is proposed. The advantages of this method are its being able to use the previous ciphertext as a seed of a new encryption process, rendering the encryption process effective in all communication process by continuous dynamic key generation together with synchronization, and its capability to cut back on system bandages to a greater extent, which is valuable for the ad-hoc circumstance. In addition, the rationality and effectiveness of this novel encryption method have been verified by the test results.展开更多
A basic procedure for transforming readable data into encoded forms is encryption, which ensures security when the right decryption keys are used. Hadoop is susceptible to possible cyber-attacks because it lacks built...A basic procedure for transforming readable data into encoded forms is encryption, which ensures security when the right decryption keys are used. Hadoop is susceptible to possible cyber-attacks because it lacks built-in security measures, even though it can effectively handle and store enormous datasets using the Hadoop Distributed File System (HDFS). The increasing number of data breaches emphasizes how urgently creative encryption techniques are needed in cloud-based big data settings. This paper presents Adaptive Attribute-Based Honey Encryption (AABHE), a state-of-the-art technique that combines honey encryption with Ciphertext-Policy Attribute-Based Encryption (CP-ABE) to provide improved data security. Even if intercepted, AABHE makes sure that sensitive data cannot be accessed by unauthorized parties. With a focus on protecting huge files in HDFS, the suggested approach achieves 98% security robustness and 95% encryption efficiency, outperforming other encryption methods including Ciphertext-Policy Attribute-Based Encryption (CP-ABE), Key-Policy Attribute-Based Encryption (KB-ABE), and Advanced Encryption Standard combined with Attribute-Based Encryption (AES+ABE). By fixing Hadoop’s security flaws, AABHE fortifies its protections against data breaches and enhances Hadoop’s dependability as a platform for processing and storing massive amounts of data.展开更多
Existing speech retrieval systems are frequently confronted with expanding volumes of speech data.The dynamic updating strategy applied to construct the index can timely process to add or remove unnecessary speech dat...Existing speech retrieval systems are frequently confronted with expanding volumes of speech data.The dynamic updating strategy applied to construct the index can timely process to add or remove unnecessary speech data to meet users’real-time retrieval requirements.This study proposes an efficient method for retrieving encryption speech,using unsupervised deep hashing and B+ tree dynamic index,which avoid privacy leak-age of speech data and enhance the accuracy and efficiency of retrieval.The cloud’s encryption speech library is constructed by using the multi-threaded Dijk-Gentry-Halevi-Vaikuntanathan(DGHV)Fully Homomorphic Encryption(FHE)technique,which encrypts the original speech.In addition,this research employs Residual Neural Network18-Gated Recurrent Unit(ResNet18-GRU),which is used to learn the compact binary hash codes,store binary hash codes in the designed B+tree index table,and create a mapping relation of one to one between the binary hash codes and the corresponding encrypted speech.External B+tree index technology is applied to achieve dynamic index updating of the B+tree index table,thereby satisfying users’needs for real-time retrieval.The experimental results on THCHS-30 and TIMIT showed that the retrieval accuracy of the proposed method is more than 95.84%compared to the existing unsupervised hashing methods.The retrieval efficiency is greatly improved.Compared to the method of using hash index tables,and the speech data’s security is effectively guaranteed.展开更多
This paper proposes a secure approach for encryption and decryption of digital images with chaotic map lattices. In the proposed encryption process, eight different types of operations are used to encrypt the pixels o...This paper proposes a secure approach for encryption and decryption of digital images with chaotic map lattices. In the proposed encryption process, eight different types of operations are used to encrypt the pixels of an image and one of them will be used for particular pixels decided by the outcome of the chaotic map lattices. To make the cipher more robust against any attacks, the secret key is modified after encrypting each block of sixteen pixels of the image. The experimental results and security analysis show that the proposed image encryption scheme achieves high security and efficiency.展开更多
In this paper, first, we investigate a novel one-dimensional logistic-PWLCM(LP) modulation map which is derived from the logistic and PWLCM maps. Second, we propose a novel PCLML spatiotemporal chaos in pseudo-rando...In this paper, first, we investigate a novel one-dimensional logistic-PWLCM(LP) modulation map which is derived from the logistic and PWLCM maps. Second, we propose a novel PCLML spatiotemporal chaos in pseudo-random coupling method that can accelerate the system behavior of the fully spatial chaos. Here, because the better chaotic properties include a wide range of parameter settings and better ergodicity than a logistic map, the LP is used in PCLML as f(x). The Kolmogorov–Sinai entropy density and universality and the bifurcation diagram are employed to investigate the chaotic behaviors of the proposed PCLML model. Finally, we apply the LP and PCLML chaotic systems to image encryption to improve the effectiveness and security of the encryption scheme. By combining self-generating matrix model M and dynamic substitution box(S-Box) methods, we design a new image encryption algorithm. Numerical simulations and security analysis have been carried out to demonstrate that the proposed algorithm has a high security level and can efficiently encrypt several different kinds of images into random-like images.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
With the development of big data and cloud computing technology,more and more users choose to store data on cloud servers,which brings much convenience to their management and use of data,and also the risk of data lea...With the development of big data and cloud computing technology,more and more users choose to store data on cloud servers,which brings much convenience to their management and use of data,and also the risk of data leakage.A common method to prevent data leakage is to encrypt the data before uploading it,but the traditional encryption method is often not conducive to data sharing and querying.In this paper,a new kind of Attribute-Based Encryption(ABE)scheme,which is called the Sub-String Searchable ABE(SSS-ABE)scheme,is proposed for the sharing and querying of the encrypted data.In the SSS-ABE scheme,the data owner encrypts the data under an access structure,and only the data user who satisfies the access structure can query and decrypt it.The data user can make a substring query on the whole ciphertext without setting keywords in advance.In addition,the outsourcing method is also introduced to reduce the local computation of the decryption process so that the outsourcing SSS-ABE scheme can be applied to IoT devices.展开更多
文摘With the rapid development of information technology,data security issues have received increasing attention.Data encryption and decryption technology,as a key means of ensuring data security,plays an important role in multiple fields such as communication security,data storage,and data recovery.This article explores the fundamental principles and interrelationships of data encryption and decryption,examines the strengths,weaknesses,and applicability of symmetric,asymmetric,and hybrid encryption algorithms,and introduces key application scenarios for data encryption and decryption technology.It examines the challenges and corresponding countermeasures related to encryption algorithm security,key management,and encryption-decryption performance.Finally,it analyzes the development trends and future prospects of data encryption and decryption technology.This article provides a systematic understanding of data encryption and decryption techniques,which has good reference value for software designers.
基金supported by the National Natural Science Foundation of China(12471416,12171124,12301567)the Heilongjiang Provincial Natural Science Foundation of China(PL2024F015)+2 种基金the Postdoctoral Science Foundation of Heilongjiang Province of China(LBH-Z22199)the Fundamental Research Foun-dation for Universities of Heilongjiang Province of China(2022-KYYWF-0141)the Alexander von Humboldt Foundation of Germany.
文摘Dear Editor,This letter deals with the distributed recursive set-membership filtering(DRSMF)issue for state-saturated systems under encryption-decryption mechanism.To guarantee the data security,the encryption-decryption mechanism is considered in the signal transmission process.Specifically,a novel DRSMF scheme is developed such that,for both state saturation and encryption-decryption mechanism,the filtering error(FE)is limited to the ellipsoid domain.Then,the filtering error constraint matrix(FECM)is computed and a desirable filter gain is derived by minimizing the FECM.Besides,the bound-edness evaluation of the FECM is provided.
基金supported by the National Natural Science Foundation of China(52273197 and 52333007)Shenzhen Key Laboratory of Functional Aggregate Materials(ZDSYS20211021111400001)+2 种基金the Science and Technology Plan of Shenzhen(JCYJ2021324134613038,JCYJ20220818103007014,KQTD20210811090142053,GJHZ20210705141810031)the Innovation and Technology Commission(ITC-CNERC14SC01)Tianjin Key Medical Discipline(Specialty)Construction Project.
文摘Luminescent nanoclusters(NCs)have attracted much attention because of their superior photophysical properties;however,the design of dynamic NCs with reversible structural change is highly challenging.Herein,we synthesize a kind of dynamic luminescent NCs through Schiff base crosslinking between triethylenetetramine(TETA)and tannic acid at room temperature.The proposed NCs have an excitation-independent blue emission,and the maximum emission is available at about 458 nm with two excitation centers.Furthermore,the crosslinking degree of the NCs can be effectively adjusted by TETA and their formation is a kineticcontrol process.Most importantly,the proposed NCs show a property of pHcontrolled reversible depolymerization and polymerization,accompanied by a cyclic“on-off-on”photoswitching,which is directly attributed to pH-stimulated reversible C=N bond cleavage and re-formation.Because of the reversible structure change properties,the dynamic NCs have been well used in reversible information encryption.This new finding provides not only us with a powerful strategy to study the structure–properties relationship of luminescent NCs but also a design idea for constructing smart optical nanomaterials.
基金financially supported by Shanghai Pujiang Program 23PJ1406500.
文摘Black wings of butterfly Ornithoptera goliath and infrared-band radiative cooling function of Rapala dioetas butterfly wings are associated with black pigment(e.g.,melanin)and unique hierarchical micro/nanostructures,greatly stimulating biomimetic fabrication of functional photonic structures but mainly targeted to one prototype.Targeted at two-prototype integrated biomimetic fabrication from fully compositional/structural/functional aspects,femtosecond(fs)laser subtractive/additive-integrated hierarchical micro/nano-manufacturing technique is proposed in this work.This technique can one-step transfer refractory metals(e.g.,W,Mo,Nb,Ta)into black non-stoichiometric oxide nanomaterials with abundant oxygen vacancies and simultaneously enable the realization of in situ quasi-controllable micro/nanoscale hierarchical aggregation and assembly,all displaying black color but with tunable infrared emission.Adjusting the scan interval for biomimetic manufacturing can tailor the structural oxidation degree,the emission in the long-wave infrared(LWIR)band while keeping the blackness of hierarchical aggregates,and the confined height between the covering quartz plate and the ablated sample.The blackening efficiency of this technique can reach∼11.25 cm^(2)·min^(−1),opening opportunities for high-throughput optical/thermal applications.Selectively patterned Chinese characters,Arabic numbers,and English letters are easily fabricable,which are intrinsically invisible-infrared dual-band encrypted but decryptable via static/dynamic environment stimuli(e.g.,sample heating/cooling,introducing external hot/cold sources including human hands).The self-evolution from‘orderless’structuring to‘ordered’functionalization is validated for the proposed fs laser subtractive/additive-integrated biomimetic manufacturing,specifically from the synthesis of diverse black nanomaterials and the seemingly disordered micro/nano-aggregates to the ordered optical/thermal regulation capacities for a delicate modulation of information encryption and decryption,unveiling a new concept for future exploration and extension.
文摘Military image encryption plays a vital role in ensuring the secure transmission of sensitive visual information from unauthorized access.This paper proposes a new Tri-independent keying method for encrypting military images.The proposed encryption method is based on multilevel security stages of pixel-level scrambling,bitlevel manipulation,and block-level shuffling operations.For having a vast key space,the input password is hashed by the Secure Hash Algorithm 256-bit(SHA-256)for generating independently deterministic keys used in the multilevel stages.A piecewise pixel-level scrambling function is introduced to perform a dual flipping process controlled with an adaptive key for obscuring the spatial relationships between the adjacent pixels.Adynamicmasking scheme is presented for conducting a bit-level manipulation based on distinct keys that change over image regions,providing completely different encryption results on identical regions.To handle the global correlation between large-scale patterns,a chaotic index-map system is employed for shuffling image regions randomly across the image domain based on a logistic map seeded with a private key.Experimental results on a dataset of military images show the effectiveness of the proposed encryption method in producing excellent quantitative and qualitative results.The proposed method obtains uniform histogram distributions,high entropy values around the ideal(≈8 bits),Number of Pixel Change Rate(NPCR)values above 99.5%,and low Peak Signal-to-Noise Ratio(PSNR)over all encrypted images.This validates the robustness of the proposed method against cryptanalytic attacks,verifying its ability to serve as a practical basis for secure image transmission in defense systems.
基金supported by the National Natural Science Foundation of China(22025503,22220102004,22401093)the Science and Technology Commission of Shanghai Municipality(24DX1400200)+2 种基金the Innovation Program of Shanghai Municipal Education Commission(2023ZKZD40)the Programme of Introducing Talents of Discipline to Universities(B16017)the China Postdoctoral Science Foundation(2023M741167,GZB20230211,2024T170273)。
文摘While biomaterials are endowed with sophisticated functions by the temporal dynamics and autonomy derived from non-equilibrium assemblies in biological systems,fabricating advanced materials counterparts with these features through kinetic control remains rare.Herein,we report a non-equilibrium hydrogel that exhibits autonomous time-dependent ultrabright fluorescence(quantum yield 0.90),achieved through the kinetically controlled incorporation of thermodynamic equilibrium host-vip complexes into a poly(2-hydroxyethyl methacrylate)(PHEMA)network.Transient complexes are programmed by coupling rapid assembly kinetics with the slow competitive binding of the polymer matrix.This kinetic mismatch converts a thermodynamic equilibrium supramolecular system into a non-equilibrium state,generating temporally dynamic fluorescence that cyclically shifts from yellow to green and self-reverts.The programmed temporal dynamics endow the hydrogel with high potential for information encryption applications.
基金Supported by the National Natural Science Foundation of China(6090317560703048)+1 种基金the Natural Science Foundation of Hubei Province(2009CBD3072008CDB352)
文摘Currently, there still lacks an efficient methodology to revoke user's ability to decrypt ciphertext in broadcast encryption with the uncertain number of ciphertext recipients. To solve this problem, here, we present a dynamic broadcast encryption scheme with the following properties: First, the length of the ciphertext has a linear relationship with the number of revocable users, but it has no association with the total number of ciphertext recipients. Sec- ond, the scheme also works when users dynamically join. Espe- cially, compared with methods published up to date, our scheme is more efficient with a large number of ciphertext recipients. Third, the broadcaster can revoke user's ability to decrypt ciphertext if necessary. Fourth, the private key of users is composed of three elements in Elliptic curve group of prime order. Last, if q-Deci- sional Multi-Exponent Bilinear Diffie-Hellman assumption holds, our scheme is secure in the standard model when a polynomial time adversary selectively attacks it.
文摘In this paper,a novel bit-level image encryption method based on dynamic grouping is proposed.In the proposed method,the plain-image is divided into several groups randomly,then permutation-diffusion process on bit level is carried out.The keystream generated by logistic map is related to the plain-image,which confuses the relationship between the plain-image and the cipher-image.The computer simulation results of statistical analysis,information entropy analysis and sensitivity analysis show that the proposed encryption method is secure and reliable enough to be used for communication application.
基金Supported by the National Natural Science Foun-dation of China (60374008)
文摘Reconfigurable computing has grown to become an important and large field of research, it offers advantages over traditional hardware and software implementations of computational algorithms. The Advanced Encryption Standard (AES) algorithm is widely applied in government department and commerce. This paper analyzed the AES algorithms with different cipher keys, adopted a novel key scheduler that generated the round key real-time, proposed a dynamically reconfigurable encryption system which supported the AES algorithm with different cipher keys, and designed the architecture of the reconfigurable system. The dynamically reconfigurable AES system had been realized on FPGA. The result proves that the reconfigurable AES system is flexible, lower cost and high security level.
基金National Natural Science Foundation of China(No.11865013)Horizontal Project of Shangrao Normal University,China(No.K8000219T)+1 种基金Industrial Science and Technology Project in Shangrao of Jiangxi Province,China(No.17A005)Doctoral Scientific Research Foundation of Shangrao Normal University,China(No.6000108)。
文摘In modern society,information is becoming increasingly interconnected through networks,and the rapid development of information technology has caused people to pay more attention to the encryption and the protection of information.Image encryption technology is a key technology for ensuring the security performance of images.We extracted single channel RGB component images from a color image using MATLAB programs,encrypted and decrypted the color images by randomly disrupting rows,columns and regions of the image.Combined with histograms and the visual judgments of encryption images,it is shown that the information of the original image cannot be obtained from the encryption image easily.The results show that the color-image encryptions with the algorithm we used have good effect and fast operation speed.Thus this algorithm has certain practical value.
文摘This paper analyzes the problems in image encryption and decryption based on chaos theory. This article introduces the application of the two-stage Logistic algorithm in image encryption and decryption, then by information entropy analysis it is concluded that the security of this algorithm is higher compared with the original image;And a new image encryption and decryption algorithm based on the combination of two-stage Logistic mapping and <i>M</i> sequence is proposed. This new algorithm is very sensitive to keys;the key space is large and its security is higher than two-stage Logistic mapping of image encryption and decryption technology.
基金This work was supported by the National Natural Science Foundation of China(61203004)the Natural Science Foundation of Heilongjiang Province(F201220)the Heilongjiang Provincial Natural Science Foundation of Joint Guidance Project(LH2020F022).
文摘In this paper,we first propose a memristive chaotic system and implement it by circuit simulation.The chaotic dynamics and various attractors are analysed by using phase portrait,bifurcation diagram,and Lyapunov exponents.In particular,the system has robust chaos in a wide parameter range and the initial value space,which is favourable to the security communication application.Consequently,we further explore its application in image encryption and present a new scheme.Before image processing,the external key is protected by the Grain-128a algorithm and the initial values of the memristive system are updated with the plain image.We not only perform random pixel extraction and masking with the chaotic cipher,but also use them as control parameters for Brownian motion to obtain the permutation matrix.In addition,multiplication on the finite field GF(2^(8))is added to further enhance the cryptography.Finally,the simulation results verify that the proposed image encryption scheme has better performance and higher security,which can effectively resist various attacks.
基金The National Natural Science Foundation of China(No.61372103)the Natural Science Foundation of Jiangsu Province(No.SBK2020020282)+1 种基金the Program of Key Laboratory of Information Network Security of the Ministry of Public Security(No.C19607)the Program of Key Laboratory of Computer Network Technology of Jiangsu Province.
文摘To share data securely with secure attribute revocation,anti-collusion,and dynamic user management in the 5G device-to-device(D2D)environment,a novel dynamic anti-collusion ciphertext policy attribute-based encryption(NDA-CP-ABE)scheme in the 5G D2D environment is proposed.On the basis of the ciphertext policy attribute-based encryption algorithm,fine-grained access control and secure attribute revocation are realized,and the confidentiality of data is guaranteed.A polynomial function is adopted in the ciphertext generation phase to realize dynamic user management.A random number is used to prevent a collusion attack among the legitimate user equipment(UE),revoked UE,and external network attackers.Finally,on the basis of the Diffie-Hellman problem,the NDA-CP-ABE scheme is formally proved,and the simulation performances are compared with those of similar schemes.The results show that data can be securely shared through a D2D channel with secure attribute revocation,anti-collusion,and dynamic user management.Moreover,compared with similar schemes,the NDA-CP-ABE scheme has higher efficiency in encryption,decryption,and storage.
基金Sponsored byNational Nature Science Foundation of China(60236010)Teaching and Research Awardfor Outstanding Teachersin Higher Education Insitutions of Ministry of Education of China
文摘A new dynamic encryption application in ad-hoc networks is proposed. The advantages of this method are its being able to use the previous ciphertext as a seed of a new encryption process, rendering the encryption process effective in all communication process by continuous dynamic key generation together with synchronization, and its capability to cut back on system bandages to a greater extent, which is valuable for the ad-hoc circumstance. In addition, the rationality and effectiveness of this novel encryption method have been verified by the test results.
基金funded by Princess Nourah bint Abdulrahman UniversityResearchers Supporting Project number (PNURSP2024R408), Princess Nourah bint AbdulrahmanUniversity, Riyadh, Saudi Arabia.
文摘A basic procedure for transforming readable data into encoded forms is encryption, which ensures security when the right decryption keys are used. Hadoop is susceptible to possible cyber-attacks because it lacks built-in security measures, even though it can effectively handle and store enormous datasets using the Hadoop Distributed File System (HDFS). The increasing number of data breaches emphasizes how urgently creative encryption techniques are needed in cloud-based big data settings. This paper presents Adaptive Attribute-Based Honey Encryption (AABHE), a state-of-the-art technique that combines honey encryption with Ciphertext-Policy Attribute-Based Encryption (CP-ABE) to provide improved data security. Even if intercepted, AABHE makes sure that sensitive data cannot be accessed by unauthorized parties. With a focus on protecting huge files in HDFS, the suggested approach achieves 98% security robustness and 95% encryption efficiency, outperforming other encryption methods including Ciphertext-Policy Attribute-Based Encryption (CP-ABE), Key-Policy Attribute-Based Encryption (KB-ABE), and Advanced Encryption Standard combined with Attribute-Based Encryption (AES+ABE). By fixing Hadoop’s security flaws, AABHE fortifies its protections against data breaches and enhances Hadoop’s dependability as a platform for processing and storing massive amounts of data.
基金supported by the NationalNatural Science Foundation of China(No.61862041).
文摘Existing speech retrieval systems are frequently confronted with expanding volumes of speech data.The dynamic updating strategy applied to construct the index can timely process to add or remove unnecessary speech data to meet users’real-time retrieval requirements.This study proposes an efficient method for retrieving encryption speech,using unsupervised deep hashing and B+ tree dynamic index,which avoid privacy leak-age of speech data and enhance the accuracy and efficiency of retrieval.The cloud’s encryption speech library is constructed by using the multi-threaded Dijk-Gentry-Halevi-Vaikuntanathan(DGHV)Fully Homomorphic Encryption(FHE)technique,which encrypts the original speech.In addition,this research employs Residual Neural Network18-Gated Recurrent Unit(ResNet18-GRU),which is used to learn the compact binary hash codes,store binary hash codes in the designed B+tree index table,and create a mapping relation of one to one between the binary hash codes and the corresponding encrypted speech.External B+tree index technology is applied to achieve dynamic index updating of the B+tree index table,thereby satisfying users’needs for real-time retrieval.The experimental results on THCHS-30 and TIMIT showed that the retrieval accuracy of the proposed method is more than 95.84%compared to the existing unsupervised hashing methods.The retrieval efficiency is greatly improved.Compared to the method of using hash index tables,and the speech data’s security is effectively guaranteed.
基金supported by the National Natural Science Foundation of China (Grant Nos. 61001099 and 10971120)the Foundation for the Author of National Excellent Doctoral Dissertation of China (Grant No. 200444)
文摘This paper proposes a secure approach for encryption and decryption of digital images with chaotic map lattices. In the proposed encryption process, eight different types of operations are used to encrypt the pixels of an image and one of them will be used for particular pixels decided by the outcome of the chaotic map lattices. To make the cipher more robust against any attacks, the secret key is modified after encrypting each block of sixteen pixels of the image. The experimental results and security analysis show that the proposed image encryption scheme achieves high security and efficiency.
基金Project supported by the National Natural Science Foundation of China(Grant Nos.61672124,61370145,and 61173183)the Password Theory Project of the13th Five-Year Plan National Cryptography Development Fund,China(Grant No.MMJJ20170203)+1 种基金the Program for New Century Excellent Talents in Fujian Province Universitythe Natural Science Foundation of Fujian Province of China(Grant No.2018J01100)
文摘In this paper, first, we investigate a novel one-dimensional logistic-PWLCM(LP) modulation map which is derived from the logistic and PWLCM maps. Second, we propose a novel PCLML spatiotemporal chaos in pseudo-random coupling method that can accelerate the system behavior of the fully spatial chaos. Here, because the better chaotic properties include a wide range of parameter settings and better ergodicity than a logistic map, the LP is used in PCLML as f(x). The Kolmogorov–Sinai entropy density and universality and the bifurcation diagram are employed to investigate the chaotic behaviors of the proposed PCLML model. Finally, we apply the LP and PCLML chaotic systems to image encryption to improve the effectiveness and security of the encryption scheme. By combining self-generating matrix model M and dynamic substitution box(S-Box) methods, we design a new image encryption algorithm. Numerical simulations and security analysis have been carried out to demonstrate that the proposed algorithm has a high security level and can efficiently encrypt several different kinds of images into random-like images.
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.
基金This work is supported by the National Natural Science Foundation of China(No.62071280,No.61602287)the Major Scientific and Technological Innovation Project of Shandong Province(No.2020CXGC010115)the Guangxi Key Laboratory of Cryptography and Information Security(GCIS201901).
文摘With the development of big data and cloud computing technology,more and more users choose to store data on cloud servers,which brings much convenience to their management and use of data,and also the risk of data leakage.A common method to prevent data leakage is to encrypt the data before uploading it,but the traditional encryption method is often not conducive to data sharing and querying.In this paper,a new kind of Attribute-Based Encryption(ABE)scheme,which is called the Sub-String Searchable ABE(SSS-ABE)scheme,is proposed for the sharing and querying of the encrypted data.In the SSS-ABE scheme,the data owner encrypts the data under an access structure,and only the data user who satisfies the access structure can query and decrypt it.The data user can make a substring query on the whole ciphertext without setting keywords in advance.In addition,the outsourcing method is also introduced to reduce the local computation of the decryption process so that the outsourcing SSS-ABE scheme can be applied to IoT devices.