probabilistic encryption

Over the past years an enormous variety of different chaosbased image and video encryption algorithms have been proposed and published. While any algorithm published undergoes some more or less strict experimental security analysis, many of those schemes are being broken in subsequent publications. In this work it is shown that three issues wrt. chaos-based encryption security considerations severely question the soundness of these techniques. It is experimentally demonstrated that obviously weak (i.e. insecure) encryption schemes do not consistently fail commonly used tests to assess chaos-based encryption security and thus, passing these test is only a necessary condition for a secure scheme, but by no means a sufficient one. Security analysis of chaos-based encryption schemes needs to be entirely reconsidered. 1st Weakness: Security-related Motivation -a major motivation often stated for chaos-based image and video encryption is a security concern when applying cryptographically secure ciphers to images with their intrinsic features

In light of security challenges that have emerged in a world with complex networks and cloud computing, the notion of functional encryption has recently emerged. In this work, we show that in several applications of functional encryption (even those cited in the earliest works on functional encryption), the formal notion of functional encryption is actually not sufficient to guarantee security. This is essentially because the case of a malicious authority and/or encryptor is not considered. To address this concern, we put forth the concept of verifiable functional encryption, which captures the basic requirement of output correctness: even if the ciphertext is maliciously generated (and even if the setup and key generation is malicious), the decryptor is still guaranteed a meaningful notion of correctness which we show is crucial in several applications. We formalize the notion of verifiable function encryption and, following prior work in the area, put forth a simulation-based and an indistinguishability-based notion of security. We show that simulationbased verifiable functional encryption is unconditionally impossible even in the most basic setting where there may only be a single key and a single ciphertext. We then give general positive results for the indistinguishability setting: a general compiler from any functional encryption scheme into a verifiable functional encryption scheme with the only additional assumption being the Decision Linear Assumption over Bilinear Groups (DLIN). We also give a generic compiler in the secret-key setting for functional encryption which maintains both message privacy and function privacy. Our positive results are general and also apply to other simpler settings such as Identity-Based Encryption, Attribute-Based Encryption and Predicate Encryption. We also give an application of verifiable functional encryption to the recently introduced primitive A.

Vulnerability of communication of digital images is an extremely important issue nowadays, particularly when the images are communicated through insecure channels. To improve communication security, many cryptosystems have been presented in the image encryption literature. This paper proposes a novel image encryption technique based on an algorithm that is faster than current methods. The proposed algorithm eliminates the step in which the secrete key is shared during the encryption process. It is formulated based on the symmetric encryption, asymmetric encryption and steganography theories. The image is encrypted using a symmetric algorithm, then, the secret key is encrypted by means of an asymmetrical algorithm and it is hidden in the ciphered image using a least significant bits steganographic scheme. The analysis results show that while enjoying the faster computation, our method performs close to optimal in terms of accuracy.

This paper presents a hybrid implementation of the RSA and Modified DES encryption and decryption ciphers, combining the strengths of both algorithms for enhanced security and performance. The RSA algorithm, based on the difficulty of factoring large prime numbers, provides strong encryption capabilities using a public-key system. However, it can be computationally expensive for large amounts of data. To address this limitation, the Modified DES algorithm, known for its efficiency, is incorporated. The key generation process involves generating the RSA key pair and a symmetric key for Modified DES. The encryption process converts plaintext blocks into numerical values, encrypts them using the RSA public key, and then further encrypts them using Modified DES with the symmetric key. This hybrid encryption technique offers a double layer of security. For decryption, the process is reversed, with Modified DES decryption followed by RSA decryption. Extensive experimentation and analysis are conducted to evaluate performance and security. The results show that the hybrid implementation achieves a balance between security and efficiency. By combining asymmetric and symmetric encryption, the approach provides enhanced protection against attacks while mitigating computational overhead. The hybrid implementation of RSA and Modified DES is a promising solution for secure communication and data protection in various applications.

A robust image encryption process is still one of the most challenging tasks in image security owing to massive degree and sensitivity nature of information in the form of pixels. The hurdles include greater computational difficulty, information loss during encryption, universality, applicability of the approach, and less scalability. Many image encryption methods existing in literature merely encrypt a portion of the data. Therefore, we propose a robust, dynamic, and sophisticated technique to enhance the encryption process to make it difficult for an attacker to gain unauthorized access to the pixel data. The proposed system uses a novel analytical research methodology through dynamically harnessing the potential of neural network that offers better forward and backward secrecy, dynamic control, and automatic management unlike any existing system. The encryption procedure comprises of two levels, first level is confusion-permutation of input image and second level is diffusion by Bit XOR operation for secure transmission and storage of images. Finally, the encrypted image is used as a target for training the Artificial Neural Network (ANN) model. ANN trained values are used for final level of encryption to develop a Neural Network (NN)-based cryptosystem, where the crypto analyst or the cracker need to know the number of adaptive iterations and the final weights for the encryption and decryption systems to crack the system which offers higher degree of resiliency towards potential threats. Results and security analysis show that our algorithm has good encryption effect, ability of resisting exhaustive attack, statistical attack, and differential attack. The system performance after implementing the proposed method is compared with existing methods present in literature with respect to processing time and Structural Similarity Index Measure (SSIM). Our proposed method offers significant reduction in encryption time and is approximately 10-15% faster than others with SSIM of 0.002165, close to zero after encryption. It also successfully balances the image quality with higher image security and lower computational complexity.

Cryptography is the science of maintaining data confidentiality, where the original text (plaintext) is encrypted using an encryption key to be ciphertext (text that has been encrypted). In this case cryptography secures data from a third party so that the third party cannot know the original contents of the data because the one who holds the key for encryption and decryption is only the sender and receiver. There are several cryptographic methods that are commonly used, one of which is DES or Data Encryption Standard. DES is included in the key-symmetric cryptography and is classified as a block cipher type

This paper presents a new hyper chaos system based on Hénon and Logistic maps which provides characteristics of high capacity, security and efficiency. The Proposed hyper chaos system is employed to generate the key for diffusion in an image encryption algorithm. The simulation experiments to the image encryption algorithm which based on the proposed hyper chaos system show that the algorithm security analysis it has large key space (10 84 that ensures a strong resistance against attack of exhaustion as the key space will be greater), strong sensitivity of encryption key and good statistical characteristics. Encryption and decryption time is suitable for different applications.

The public key cryptography based on an Overstoraged Hopfield Neural Network (OHNN) is a combination of Diffie-Hellman public key cryptosystem and probabilistic symmetric-key encryption scheme with chaotic-classified properties. Keep the random permutation operation of the neural synaptic matrix as the secret key, and the neural synaptic matrix after permutation as public-key. Because of the principal applications of generalized inverses is to the solution of linear systems and matrix equations in the singular case, we use the generalized inverse of matrices to demonstration that the transform function of the neural synaptic matrix is trapdoor one-way function. It lays a good foundation to design a provably secure public-key encryption scheme.

Image encryption is an efficient and vital way to protect classified and secret images. With the advancement of the processing power of the computer, AES, DES, or chaotic series type just alike image encryption schemes are not as secure as before. Therefore, in this paper, we present a new hybrid image encryption method for protecting secret and imperative images by employing logistic sine system (LSS) together with two-dimensional cellular automata and FSM-based DNA rule generator. The secure hash (SHA-256) algorithm is used to generate a secret key and to compute initial values for the LSS. In our proposed method, there are three stages and each stage has its own rule. After the scrambling process, the first stage is the Feistel structure-based bit inversion (FSBI) to change the pixels' value. The second stage is 2D-CA with Moore neighborhood structure-based local rules. The third is DNA conversion based on finite-state machine (FSM-DNA) rule generator. The proposed encryption scheme is robust against the well-known attacks, such as statistical attacks, brute force attacks, differential attacks, and pixel correlation attacks, and also possesses strong key sensitivity. The results show that our three-layer hybrid image encryption technique is robust against many well-known attacks and can be applied directly to all types of classified gray-scale images to make them more secure from such cryptography attacks.

Cybersecurity is a significant part of safe data transmission, particularly through networks such as the Internet. Confidential medical or military images and personal images of individuals and organizations are a big part of such data. These images need a very high level of security to prevent access by unauthorized users. Unauthorized access to such images can lead to significant financial and life losses. To prevent this, we incorporate various encryption-decryption algorithms and concepts like steganography into a system for safe, reliable, efficient, and secure image storage and transfer. We tune each algorithm implemented in the system individually to produce the best results upon integration with other algorithms. Further, we provide users with Graphic User Interface that helps them interact with this system conveniently and efficiently. Finally, we test the system using various medical images and present the results.

There are many ways to ensure data security, one of the classic way but still effective is to use encryption. Encryption itself has two techniques or algorithms: symmetric-key (also called secret-key) and asymmetric-key encryption (also called public key). In this paper, we proposed an analysis of two algorithm of encryption: RSA and AES algorithm in term of securing digital data. The method used in this research are: RSA and AES analysis, then retrieving the result. The two algorithm is deeply and thoroughly analyzed to discover the effectiveness to secure the data. The Technological Readiness Level (TKT) is at level 6, which means demonstration of a model or prototype or the analysis result of a system or subsystem or a study in a relevant environment. The result concluded that the application of the AES encryption algorithm is more optimal than RSA encryption in digital data security. Because the encryption and decryption process of using the AES algorithm is faster, although the...

Traditional cryptographic encryption can achieve provable security but is unfortunately sensitive to a single bit error, which will cause an unreliable packet to be dropped to create packet loss. In order to achieve robust media encryption, error resilience in media encryption can be treated to be equivalent to error resilience in media transmission. This study proposes an embedded block hash searching scheme at the decoder side to achieve motion estimation and recover the lost packets, while maintaining format compliance and cryptographic provable security. It is important to note that the proposed framework is a kind of joint error-resilient video transmission/encryption and copyright protection.

In recent years, the chaos based cryptographic algorithms have suggested some new and efficient ways to develop secure image encryption techniques. In this communication, we propose a new approach for image encryption based on chaotic logistic maps in order to meet the requirements of the secure image transfer. In the proposed image encryption scheme, an external secret key of 80-bit and two chaotic logistic maps are employed. The initial conditions for the both logistic maps are derived using the external secret key by providing different weightage to all its bits. Further, in the proposed encryption process, eight different types of operations are used to encrypt the pixels of an image and which one of them will be used for a particular pixel is decided by the outcome of the logistic map. To make the cipher more robust against any attack, the secret key is modified after encrypting each block of sixteen pixels of the image. The results of several experimental, statistical analysis and key sensitivity tests show that the proposed image encryption scheme provides an efficient and secure way for real-time image encryption and transmission.

In this paper, we present a lossless image encryption algorithm utilizing robust chaos based dynamic DNA coding and DNA operations (DNA XOR and DNA Complement). The entire process of encryption is controlled by the pseudo-random number sequences generated through a 1D robust chaos map that exhibits chaotic behaviour in a very large region of parameter space with no apparent periodic window and therefore possesses a fairly large key space. Due to peculiar feed-forward and feedback mechanisms, which modify the synthetic image (created to initiate the encryption process) at the encryption of each pixel, the proposed algorithm possesses extreme sensitivity to the plain image, cipher image and secret key. The performance analysis proves that the proposed algorithm exhibits excellent features (as expected from ideal image encryption algorithms) and is robust against various statistical and cryptanalytic attacks.

Recently, many image encryption algorithms based on hybrid DNA and chaos have been developed. Most of these algorithms utilize chaotic systems exhibiting dissipative dynamics and periodic windows/patterns in the bifurcation diagrams along with co-existing attractors in the neighborhoods of parameter space. Therefore, such algorithms generate several weak keys, thereby making them prone to various chaos- specific attacks. In this paper, we propose a novel conservative chaotic standard map-driven dynamic DNA coding (encoding, addition, subtraction and decoding) for image encryption. It is the first hybrid DNA and conservative chaos-based image encryption algorithm having effectively infinite key space. The proposed image encryption algorithm is a dynamic DNA coding algorithm i.e., for the encryption of each pixel different rules for encoding, addition/subtraction, decoding etc. are randomly selected based on the pseudorandom sequences generated with the help of the conservative chaoti...

Recent advancements in wireless technology have created an exponential rise in the number of connected devices leading to the internet of things (IoT) revolution. Large amounts of data are captured, processed and transmitted through the network by these embedded devices. Security of the transmitted data is a major area of concern in IoT networks. Numerous encryption algorithms have been proposed in these years to ensure security of transmitted data through the IoT network. Tiny encryption algorithm (TEA) is the most attractive among all, with its lower memory utilization and ease of implementation on both hardware and software scales. But one of the major issues of TEA and its numerous developed versions is the usage of the same key through all rounds of encryption, which yields a reduced security evident from the avalanche effect of the algorithm. Also, the encryption and decryption time for text is high, leading to lower efficiency in IoT networks with embedded devices. This paper...

With the rapid development of military applications and advanced warfare between the nations, the building of network and communication technology, transmitting sensible information across troops has become a necessary way of information transmission. Therefore, much more attention has been paid to the development of the image encryption technology for military applications. In this paper, we propose a image encryption technology based on AES algorithm, and the algorithm implementation in GNC/GCC. Then, we perform image processing, obtain the password text that can use the AES encryption algorithm, combine both password and secured image. Then, the digital image can be encrypted, and the algorithm is realized in GNU simulation. Through the comparison of the histogram analysis and the analysis of the key, the result has showed that the method can better realize the effect of encryption and decryption with more security for image transmission.

Security is becoming much more important in data storage and transmission. Cryptography has come up as a solution which plays a vital role in information security system against malicious attacks. This security mechanism uses some algorithms to scramble data into unreadable text which can be only being decoded or decrypted by party those possesses the associated key. These algorithms consume a significant amount of computing resources such as CPU time, memory and computation time. In this paper we are studying the performance evaluation of the various encryption algorithms and also we are analyzing the best encryption algorithm from the widely used algorithms.

In the today's world, security is required to transmit confidential information over the network. Security is also demanding in wide range of applications. Cryptographic algorithms play a vital role in providing the data security against malicious attacks. Encryption of data is an important topic for research, as secure and efficient algorithms are needed that allow optimized encryption and decryption of data. In this paper we propose a new encryption algorithm, called Reverse Encryption Algorithm (REA). Our new encryption algorithm (REA) is simple and fast enough for most applications. REA encryption algorithm provides maximum security and limits the added time cost for encryption and decryption.

In this work, we present an encryption algorithm that can be used to for hardware-implemented applications to secure data communications. This encryption algorithm is based on hiding a number of bits from plain text message into a random vector of bits. The locations of the hidden bits are determined by a key known to the sender and receiver. We call this algorithm hybrid hiding encryption algorithm (HHEA). The name demonstrates the two basic operations of this algorithm. These are operations include inserting part of the plaintext bits into a cover to hide it from recognition. That is there are no conventional operations on the ciphered text, just plain hiding in a random bit string. The name "Hybrid" is used to show that the algorithm has built-in features that are inherited from data hiding techniques or "Steganography." The distinctive features of this algorithm are as follows: • Key length is variable: the key length can be varied from 16 up to any larger value depending on the security level required. • Word length is variable: the block size can be varied between 1 to 16 bit or 1 to 32 and so on. That is, encryption can be performed on 16 or 32 or 64 bit blocks. This, in turn, can be used on different processor architectures employing 16, 32, or 64 bit registers. • The algorithm, therefore, provides variable degrees of security. However, this increased security level will be at the cost of increased size of the cipher-text. • The number of rounds is variable: the whole process can be repeated r times using the same key. The method is quite suitable for hardware implementation employing Field programmable gate arrays (FPGA).

Digital communication of multimedia data (text, signal/audio, image, and video) through the internet network has an important role in the era of industrial revolution 4.0 and society 5.0. However, the easiness of exchanging personal and confidential digital information/data has a high risk of being hijacked by irresponsible people. The development of reliable and robust data encryption methods is a solution to this risk. This paper suggests combining modified Henon Map transposition encryption and Logistic Map keystream substitution encryption to create a novel data encryption method (called RaMSH-1). The proposed algorithm simultaneously transposes data positions and substitute data values randomly, as well as having encryption key combination or key space of 1.05 × 10 670. A few images with various sizes and variations of color features, object shapes, and textures have been tested. Based on the results of the analysis of randomness, key sensitivity, and visual, it is evident that the proposed encryption algorithm is resistant to differential attack, entropy attack and brute force attack.

This article explores the application of the Walsh system in modern data encryption methods. The advantages and limitations of this system are reviewed and its effectiveness is analyzed in comparison to other encryption schemes. The article describes the mathematical basis of the Walsh transform, its use for encryption and decryption, and its practical applications. In conclusion, prospects for further research in this area are considered.

This article explores the application of the Walsh system in modern data encryption methods. The advantages and limitations of this system are reviewed and its effectiveness is analyzed in comparison to other encryption schemes. The article describes the mathematical basis of the Walsh transform, its use for encryption and decryption, and its practical applications. In conclusion, prospects for further research in this area are considered.

Recently, the concept of DNA has been invested in computing technology in different ways which linking information technology and biological sciences. There are several encryption algorithms based on DNA encoding that has been proposed, which leads to generating a new direction in image encryption. However, the DNA encryption scheme has drawbacks such as expensive experimental equipment, difficult operations, and hard to hold its biotechnology. Additionally, during careful cryptanalysis that applied to most of these image encryption schemes, we notice that DNA operators can only influence one DNA base, which causes poor diffusion. Our proposed scheme is not applied complex biological operation but just is given to improve the diffusion ability of image encryption scheme by using DNA sequence and DCT transform. Our works overcome above-aforementioned issues. Furthermore, empirical results on real images and security analysis demonstrate that our proposed scheme not only has flexibili...

Nowadays, with the widespread of the Internet of Things (IoT) applications in every aspect of our lives. It's urgent to protect the sensitive data such as images generated by IoT devices transmitted through the wireless network. Furthermore, IoT devices are considered constraint devices regarding limited computation resources such as processing and memory size. Thus, classical encryption methods are not appropriate due to their complex computation resources. Therefore, in this paper, we proposed a new lightweight encryption algorithm based on the DNA sequence to be adequate for IoT device's resources. In the proposed algorithm, we utilized the DNA sequence random nature to generate a strong secret key, which is hard to be broken by attackers. The DNA key is used to encrypt images by two simple and robust substitution and transposition operations where they meet the requirements of IoT computation resources and the protection of the transmitted images. Moreover, the experimental results show outstanding results regarding key size, encryption time, and preparation of distortion compared with other encryption algorithms.

The need for a reliable and fast encryption algorithm to encrypt medical data for patients is an extremely important topic to be considered especially during pandemic times such as the pandemic COVID-19. This pandemic forced governments and healthcare institutions to monitor COVID-19 patients. All the patient's data or records are also shared among healthcare researchers to be used to help them find vaccines or cures for this pandemic. Therefore, protecting such data (images, text) or records face an everincreasing number of risks. In this paper, a novel multi-round encryption algorithm based on deoxyribonucleic acid (DNA) is proposed. The significance of the proposed algorithm comes from using a different random key to perform simple and fast encryption operations on multiple rounds to achieve a high level of confusion and diffusion effects in encrypted data. Experiments were conducted using a set of datasets of various types such as Excel sheets, images, and database tables. T...

In this digital world, images are an important part of communication and while communicating security is a crucial problem. And to deal with security various image encryption techniques are based on the cellular automata. The study gives a basic introduction to cryptography and cellular automata and various encryption scheme based on cellular automata. Various performance measures related to the analysis of encryption techniques have been studied. And a comparison of encryption techniques based on the performance matrices is presented. The paper gives a concluding remark on the advancement in the field of image encryption.

The authors in the article propose two modifications of the method of image encryption based on the use of the ideas underlying the algorithm RSA, in particular the combination of the properties of the RSA algorithm and bitwise additively-difference operations. The advantage of these methods is to maintain resistance to decrypt, which is provided by the RSA algorithm and eliminating the use of visual methods of image processing for decryption. The methods shows best results in the case that makes it easy to highlight contours of images .

Sending digital pictures across open networks has emerged as a major privacy risk in recent years. Despite the environment's adaptability and the many benefits it offers, there are, however, a significant number of threats to one's privacy and safety. A great number of cryptosystems have been proposed in the literature on picture encryption in an effort to make communication more secure.  For the purpose of data transmission, the AES algorithm is utilized due to the increased efficiency it offers in the block. This paper proposes image encryption techniques based on the AES algorithm and Henon map. The plain image has been encrypted using the AES algorithm at the first step. Then, the Henon map is used to generate a random key which is required to provide the second step of encryption. This step of encryption has been performed using the XOR operation. The results of the studies demonstrate that the strategy proposed resolves the issues that are present in conventional techn...

In today’s world, security and protection issues of the transmitted information have turned into a vital worry in media innovation. In the course of the most recent couple of years a few encryption algorithms have connected to secure video transmission. While countless encryption plans have been proposed in the literature and some have been utilized as a part of genuine items, cryptanalytic work has demonstrated the presence of security issues and different shortcomings in the greater part of the proposed interactive media encryption plans. In this paper, International Data Encryption Algorithm (IDEA) is a symmetric key encryption method and utilizations 128 -bitkey more than 64-bit plain content with eight and a half round. To improve the innovation in IDEA, another methodology is presented in which we will set up two distinctive keys for encryption and decoding separately which was single key in IDEA. This will present more security in IDEA by making it an asymmetric key encryptio...

Many encryption algorithms are designed to decrease the probability of cyberattacks by assuring data security as well as system and participant authentication. However, in the development of computer resources cryptanalytical techniques have been developed and performed competitively in information security with good results. In this paper, we reported security flaws in the recently offered encryption technique based on a chaotic map for Internet of Health Things (IoHT) security. The scheme was based on a new chaotic map, modified Mandelbrot set, and conditional shift algorithm asserting the encryption algorithm is secure. We have performed some cryptographic attacks to retrieve the key from the understudy cryptosystem. The key was retrieved in little computation by using a chosen-plaintext attack and one known plaintext ciphertext pair. The minimum execution time of performed attacks indicates the vulnerability of the diffusion-based encryption algorithm. To enhance the security of the understudy cryptographic algorithm, we have also suggested certain improvements. INDEX TERMS Chaotic map, chosen-plaintext attack, conditional shift, cryptanalysis, Internet of Health Things, known-plaintext attack.

Chaotic encryption is a growing field for competently shielding visual data. As well as quantum encryption and substitution also play a significant role in applied fields owing to its prospective use in secure communication. This article offers new method for the encryption by utilizing quantum chaotic maps and continuous chaotic dynamical systems. Since chaotic maps are itself suitable for quality encryption coupled with quantum logistic encryption, substitution box stipulates highly secure encryption program. Quantum logistic map is combined with Liu and Rossler chaotic systems with the intention of improvement in efficiency of data randomness. Designed scheme ensures the security of data with the minimum time of encryption. Outcomes acquired from performance evaluation signifies that projected chaotic encryption program reveals high complexity and security.

Many encryption algorithms are designed to decrease the probability of cyberattacks by assuring data security as well as system and participant authentication. However, in the development of computer resources cryptanalytical techniques have been developed and performed competitively in information security with good results. In this paper, we reported security flaws in the recently offered encryption technique based on a chaotic map for Internet of Health Things (IoHT) security. The scheme was based on a new chaotic map, modified Mandelbrot set, and conditional shift algorithm asserting the encryption algorithm is secure. We have performed some cryptographic attacks to retrieve the key from the understudy cryptosystem. The key was retrieved in little computation by using a chosen-plaintext attack and one known plaintext ciphertext pair. The minimum execution time of performed attacks indicates the vulnerability of the diffusion-based encryption algorithm. To enhance the security of the understudy cryptographic algorithm, we have also suggested certain improvements. INDEX TERMS Chaotic map, chosen-plaintext attack, conditional shift, cryptanalysis, Internet of Health Things, known-plaintext attack.

In current years many chaos-based Substitution boxes (S-boxes) have been proposed. Recently, an image encryption technique based on multiple chaotic S-box was offered. This encryption method was based on the concept of confusion only produced by the implementation of the S-box. The concept of confusion utilized in the understudy technique can be smashed by using just one chosen-plaintext attack and a chosen-ciphertext attack. This article presents a detailed structure of two types of cryptographic attacks on the diffusion-based encryption scheme. The proposed attacks are successfully performed to retrieve the key with very little execution time by using just one chosen image which indicates the vulnerability of multiple chaotic S-boxes-based cryptosystems. The retrieved data is passed through some statistical analysis such as correlation, histogram, and entropy to check the correctness of recovered data.

Chaotic encryption is a growing field for competently shielding visual data. As well as quantum encryption and substitution also play a significant role in applied fields owing to its prospective use in secure communication. This article offers new method for the encryption by utilizing quantum chaotic maps and continuous chaotic dynamical systems. Since chaotic maps are itself suitable for quality encryption coupled with quantum logistic encryption, substitution box stipulates highly secure encryption program. Quantum logistic map is combined with Liu and Rossler chaotic systems with the intention of improvement in efficiency of data randomness. Designed scheme ensures the security of data with the minimum time of encryption. Outcomes acquired from performance evaluation signifies that projected chaotic encryption program reveals high complexity and security.

The privacy of digital contents is one of the most important issue of the digitally advanced world. The transmission of online information is increasing immensely from last one decade. As the technology evolving with the passage of time, the secrecy of digital information is one of the unavoidable problem. The secrecy of information can be achieved through different encryption algorithms. In this article, our aim is to introduce an innovative technique for an image encryption to extend the advanced encryption standard (AES) to the Galois field of any characteristic. With the new improvement, all four steps in basic algorithm with binary characteristic is modified accordingly. We have extended number of possibilities in our proposed substitution boxes which imply, we added more confusion capabilities and generalized the existing concepts. Moreover, we have applied the anticipated scheme to digital image encryption. We have utilized standard statistical to verify the robustness of our suggested technique for encrypted image.

In the current context, ensuring the secure transmission of data over the internet has become a critical concern, with information technology playing a fundamental role. As society advances into the digital information age, the importance of network security issues continues to increase. Therefore, the need for cryptographic technology has emerged to overcome these challenges. Cryptography includes symmetric and asymmetric cryptography. An example of symmetric cryptography is the RC2 algorithm. RC2 is a symmetric encryption algorithm that uses a single key to encrypt and decrypt data. The ciphertext is then concealed within an image using the Stepic technique. The RC2 encryption method also utilizes symmetric encryption, ensuring the security of the encryption process while maintaining efficient encryption and decryption speeds. The result of this research is that the average percentage of MSE is 0.00%, and for PSNR and AVA are 70.85% and 34.93%. However, the AVA value is quite unstable because the average value is below 40%. Meanwhile, image encryption results in the longer the text that needs to be hidden in the image, the higher the UACI percentage. This is inversely proportional to the NPCR, the longer the text that needs to be hidden in the image, the lower the NPCR percentage. The average results obtained for UACI and NPCR values are 41.46% dan 98.13%.

Searchable encryption techniques are intelligent tools that attempt to solve the challenge of querying stored data on untrusted cloud servers while preserving data confidentiality. This paper proposes simple, powerful, and practical Searchable Symmetric Encryption (SSE) scheme which capable of executing SQL (Structural Query Language) queries over encrypted cloud databases. Our scheme improves the efficiency of the search over encrypted data by using the SCKHA (Symmetric Cipher based on Key Hashing Algorithm) algorithm instead of using the bloom filter technique which causes the problem of the false positives. We built a complicated index structure for the encrypted data by combining the encryption of the data unit using Advanced Encryption Standard (AES) scheme with the encryption of SCKHA scheme for the same data to ensure data security. We also proposed a complete framework for implementing our construction, validating its practicality to achieve exact and partial search over encrypted SQL databases. Furthermore, we performed experiments on adult data sets and analyzed the experimental results in terms of computation time for index generation, trapdoor generation and average search. Experiments showed that the taken time for generating the trapdoor and the keyword search in our scheme is faster than other schemes. We also analyzed the security of our scheme and evaluated its performance experimentally and theoretically. Finally, we provide features for evaluating single, conjunctive, and disjunctive queries.

Two new encryption algorithms for secure video transmission are proposed in this paper. The two algorithms employ different types of chaotic maps to generate the keystream for encrypting the video frames. Both algorithms involve a substitution step and a permutation step to achieve confusion and diffusion requirements. For efficient transmission, the video file is compressed before being encrypted. In the basic implementation of both algorithms, MPEG-2 standard is used for compression. However, the algorithms are shown to be compliant with other compression techniques. In the permutation step, the effect of the block size used in the shuffling process is examined. Smaller blocks result in increasing the processing time, while reducing both the correlation between adjacent pixels and the peak-signal-to noise ratio of an encrypted frame. The use of a Feistel structure is investigated to enhance security and its negative impact on the encryption time is demonstrated. The experimental results of the two proposed schemes confirm that they represent different tradeoffs between security and computational efficiency. Both schemes are sensitive to slight variations in the encryption key as apparent from the obtained differential measures. The conducted comparative study shows the competitiveness of the proposed schemes to existing schemes in literature.

In various cloud computing models, the data need to be protected and to access these data in secure manner is important. The cryptographic key which is used to secure these data using both in the encryption as well as in decryption it is mandatory to manage these keys to secure these keys by disclosing in public networks such as any wireless and cloud environment. Utilizing Ciphertext Policy Attribute-based Encryption (CP-ABE), which provides effective data governance and key management, for cloud data encryption. The work based on the combination of Cipher Text-Policy Attribute based Encryption and Proxy Re-Encryption is elaborated in the article (CP-ABE-PRE). The encrypted data should ideally be transformed such that it may be unlocked with new keys, without an intermediate decryption step that would allow the cloud provider to read the plaintext this process is known as data re-encryption. The computational and communication burden on users connecting to the cloud from resource c...

Mobile Ad-hoc NETworks (MANETs) are expected to play an important role in tactical military networks by providing infrastructureless communication. However, maintaining secure and instant information sharing is a difficult task especially for highly dynamic military MANETs. To address this requirement, we propose a new multi-tier adaptive military MANET security protocol using hybrid cryptography and signcryption. In our protocol, we bring novelties to secure military MANET communication for three main points: Cryptographic methods used in MANETs, hybrid key management protocols and structural organization of the military MANETs. As a new approach, we use hybrid cryptography mechanisms and Elliptic Curve Pintsov-Vanstone Signature Scheme (ECPVSS) that provide security and performance advantages when compared to some traditional cryptographic methods. Furthermore, multi-leveled security approach of our protocol provides adaptive solutions according to the requirements of different military units in the MANET. We also use a hybrid key management technique that combines the benefits of both decentralized protocols with single point of failure resistivity and centralized protocols with low rekeying cost. Last, the proposed network structure facilitates certification and key management for the MANET by providing flexibility for Mobile Backbone Network (MBN) tiers.

Ensuring the security of data while being transmitted or stored is a very important issue for companies and end users. Cryptography is used to transfer the data in a form that is not understood by anyone apart from the intended recipients. The advanced standard encryption algorithm (AES) is one of the most secure encryption algorithms. However, due to the speed issue and computational complexity, it is not suitable for real time applications. In this paper, a modified scheme is developed for the encryption/decryption by modifying the MixColumns stage in the AES algorithm in order to increase the speed of the encryption/ decryption while maintaining the complexity level of the design to keep the security level equivalent to AES. The results show that the proposed modification increases the speed of the encryption/decryption in real time applications up to 150% in the encryption process and up to 500% in the decryption process.

This paper proposes a hyperchaos-based image encryption algorithm, which consists of two scrambling-diffusion operations and one scrambling operation. In the proposed algorithm, the initial conditions of a hyperchaotic Chen system are first generated using the Message Digest 5 (MD5) value of digital images and given initial values, and then the images will be encrypted using the keystream created by the system. Since the initial values of hyperchaotic Chen systems are related to plaintext and the encryption process is related to the images, this algorithm is able to effectively protect images against selective plaintext attacks. Simulation results demonstrate that the present algorithm offers enhanced encryption performance, high security, and strong resistance to known attacks. Therefore, it may find wide application in image encryption transmission. Compared to other image encryption algorithms, the proposed algorithm uses different keystreams when encrypting different images and ...

Ensuring the security of data while being transmitted or stored is a very important issue for companies and end users. Cryptography is used to transfer the data in a form that is not understood by anyone apart from the intended recipients. The advanced standard encryption algorithm (AES) is one of the most secure encryption algorithms. However, due to the speed issue and computational complexity, it is not suitable for real time applications. In this paper, a modified scheme is developed for the encryption/decryption by modifying the MixColumns stage in the AES algorithm in order to increase the speed of the encryption/ decryption while maintaining the complexity level of the design to keep the security level equivalent to AES. The results show that the proposed modification increases the speed of the encryption/decryption in real time applications up to 150% in the encryption process and up to 500% in the decryption process.

ElGamal public key encryption scheme has been designed in the 80's. It is one of the first partial homomorphic encryption and one of the first IND-CPA probabilistic public key encryption scheme. A linear version has been recently proposed by Boneh et al. In this paper, we present a linear encryption based on a generalized version of ElGamal encryption scheme. We prove that our scheme is IND-CPA secure under linear assumption. We design a generalized ElGamal scheme from the generalized linear. We also run an evaluation of performances of our scheme. We show that the decryption algorithm is slightly faster than the existing versions.