This study investigates the most recent data hiding techniques based on DNA steganography, including the highly improved DNA-based steganography technique, the data hiding using double DNA sequences method, and the enhanced DNA-based steganography technique. The strengths and weaknesses of these techniques are discussed. Additionally, the security of these techniques is analyzed based on several security parameters that measure the quality of DNA steganography with respect to many factors, including, but not limited to, cracking probability, blindness, modification rate and expansion rate, and layers of security. The goal of the comparison between the investigated techniques is to highlight the advantages and disadvantages of the existing data hiding algorithms and to motivate future research in this field. Moreover, the paper evaluates the discussed techniques based on some parameters, including capacity, payload, and bit per nucleotide (bpn). The result shows that the enhanced DNA-based steganography technique hides 2 bpn, whereas the highly improved method can hide on average 1.46 bpn, which is higher than data hiding using double DNA sequences method can hide .The paper also presents suggestions for how each technique can be optimized to to achieve a higher security level for hiding data within DNA sequences.

Cryptography is a scientific method that is used to transmit secret information. In contrast, quantum cryptography depends on physical laws to encrypt information; when the quantum computer appeared, the classic encryption method becomes inefficient. The quantum method is commonly used to distribute keys, a process called as quantum key distribution (QKD). In this paper, we consider the efficiency of the quantum method compared to classical methods. Also, we discuss the security of QKD against several attacks and provide security analysis based on probabilistic models. Additionally, the paper explains how to encrypt random numbers into a sequence of photons using a QKD system for the distribution of a key. This research demonstrates the efficiency and security of QKD in sending and distributing keys between communication parties. Thus, both the sender and the receiver would be able to obtain a security key using the quantum method rather than classical methods.

Cloud computing has revolutionized the world, opening up new horizons with bright potential due to its performance, accessibility, low cost, and many other benefits. Cloud computing is the on-demand availability of computer system resources, especially data storage (cloud storage) and computational power. Cloud computing refers to data centers accessible to numerous customers over the Internet. It has the ability to utilize computing resources at a low cost and fast speed. Cloud data security is becoming increasingly important as we shift our devices, data centers, business processes, and other assets to the cloud. Comprehensive security policies, corporate security culture, and cloud security solutions are used to ensure the level of cloud data security. Many techniques exist to protect data communication in the cloud environment, including encryption, which is the primary component of data security and the mechanism by which data or message transmission confidentiality and integrity are achieved. Current researchers have focused on genetics-based cryptography; genetics has been implemented in cryptography for data computation, storage, and transmission. This survey paper analyzes the new type of cryptographic approaches based on genetic science to generate robust sub-keys and robust cryptographic techniques based on homologous genetics (DNA, RNA, and mRNA) to improve security in the cloud. This work reviews several approaches based on genetic cryptography and their applications and drawbacks. In addition, the paper introduces the architecture of cloud computing along with the fundamental challenges of cloud computing applications.

Information security has become increasingly challenging as a result of massive advancements in information and communication technologies. Due to the necessity of exchanging private information and the open nature of the network, there is an increased risk of various types of attacks. Consequently, data security is an essential component of data communication. One of the most effective methods used to achieve secrecy is steganography. This method hides data within a cover object without raising suspicion. The level of security is improved when two steganography methods are combined. This approach is known as multilevel steganography, which hides sensitive data in two cover objects in order to provide a two-level security system. Accordingly, we developed a technique that focuses on protecting secrecy while also being robust to attacks. The new technique uses a multi-layer steganography mechanism by using DNA sequences and images as carriers for sensitive data. The technique intends to hide secret messages in the DNA using the substation algorithm, and then the fake DNA is embedded in an image utilizing the discrete cosine transform (DCT) method. Eventually, the stego image is sent to the intended recipient. Different types of images with different sizes and lengths of messages and DNA sequences were used during the experiments. The results show that the proposed mechanism is resistant to histogram and chi-square attacks. The maximum mean value observed was 0.05, which means the histograms of the original and stego images are nearly identical, and the stego image does not raise any suspicion regarding the existence of secret information. In addition, the imperceptibility ratios were good, as the highest PSNR and MSE values were 0.078 and 72.2, respectively. Finally, the PNG and BMP images show excellent results. On the other hand, the JPG images failed to meet the expected ratio of imperceptibility and security.

The rapid growth of electronic assessment in various fields has led to the emergence of issues such as user identity fraud and cheating. One potential solution to these problems is to use a complementary authentication method, such as a behavioral biometric characteristic that is unique to each individual. One promising approach is keystroke dynamics, which involves analyzing the typing patterns of users. In this research, the Deep Belief Nets (DBN) model is used to implement a dynamic keystroke technique for secure e-assessment. The proposed system extracts various features from the pressure-time measurements, digraphs (dwell time and flight time), trigraphs, and n-graphs, and uses these features to classify the user's identity by applying the DBN algorithm to a dataset collected from participants who typed free text using a standard QWERTY keyboard in a neutral state without inducing specific emotions. The DBN model is designed to detect cheating attempts and is tested on a dataset collected from the proposed e-assessment system using free text. The implementation of the DBN results in an error rate of 5% and an accuracy of 95%, indicating that the system is effective in identifying users' identities and cheating, providing a secure e-assessment approach.

Environmental monitoring devices based on IoT collect a large amount of data about the environment and our surroundings. These data are collected and processed before being uploaded to third-party servers and accessed and viewed by ordinary or specialized users. However, they may hold sensitive information that should not be exposed to unauthorized users. Therefore, accessing this sensitive information must be strictly controlled and limited in order to prevent unauthorized access. This research intends to create an access control mechanism based on distributed ledger technologies. The idea is to use a hybrid of IOTA technology and Ciphertext-Policy Attribute-Based Signcryption (CP-ABSC) technology. The permissions to access these data are written in a token, and this token will be sent to the Tangle after being signcrypted with CP-ABSC. Consequently, the data will be safeguarded, their confidentiality and integrity will be maintained, and unauthorized individuals will be unable to access the information. The proposed system was evaluated in terms of performance and the results showed that the system is straightforward, rapid, and convenient to use. Furthermore, a security assessment was conducted by running several scenarios to evaluate its feasibility and protection.