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Conventional luminescent information is usually visible under either ambient or UV light, hampering their potential application in smart confidential information protection. In order to address this challenge, herein, light‐triggered luminescence ON‐OFF switchable hybrid hydrogels are successfully constructed through in situ copolymerization of acrylamide, lanthanide complex, and diarylethene photochromic unit. The open‐close behavior of the diarylethene ring in the polymer could be controlled by UV and visible light irradiation, where the close form of the ring features fluorescence resonance energy transfer with the lanthanide complex. The hydrogel‐based blocks with tunable emission colors are then employed to construct 3D information codes, which can be read out under a 254 nm UV lamp. The exposure to 300 nm UV light leads to the luminescence quenching of the hydrogels, thus erasing the encoded information. Under visible light (>450 nm) irradiation, the luminescence is recovered to make the confidential information readable again. Thus, by simply alternating the exposure to UV and visible lights, the luminescence signals could become invisible and visible reversibly, allowing for reversible multiple information encryption and decryption. Light‐triggered luminescence ON‐OFF switchable hybrid hydrogels are synthesized through in situ copolymerization. The hydrogel‐based blocks with tunable emission colors are then employed to construct 3D information codes, allowing for reversible multiple information encryption and decryption.

Exploring high‐safety but convenient encryption and decryption technologies to combat threats of information leakage is urgently needed but remains a great challenge. Here, a synergistically time‐ and temperature‐resolved information coding/decoding solution based on functional photonic inks is demonstrated. Encrypted messages can be stored into multiple channels with dynamic‐color patterns, and information decryption is only enabled at appointed temperature and time points. Notably, the ink can be easily processed into quick‐response codes and multipixel plates. With high transparency and responsive color variations controlled by ink compositions and ambient temperatures, advanced 3D stacking multichannel coding and Morse coding techniques can be applied for multi‐information storage, complex anticounterfeiting, and information interference. This study paves an avenue for the design and development of dynamic photonic inks and complex encryption technologies for high‐end anticounterfeiting applications. Here, a synergistically time‐/temperature‐resolved information coding/decoding solution based on a photonic anticounterfeiting ink is demonstrated. The ink can be easily processed into different patterns, which enable the storage of messages into multiple channels as well as the information decryption at appointed temperature and time points, providing inspirations for advanced information‐encryption and anticounterfeiting technologies.

To enhance privacy protection for specific regions within an image while preserving its overall visual integrity, this paper presents a visual encryption algorithm targeting partial privacy-sensitive areas. Initially, an improved time-varying delayed exponentially controlled chaotic system (1-TDEC) is proposed. It utilizes the current precision value to modify the system input in a time-varying manner, effectively alleviating the dynamic degradation, and making it more suitable for image encryption algorithm designs. Subsequently, the Mask-RCNN instance segmentation model is incorporated to capture the pixel coordinates of different contents in the image, allowing for access to specific area information as required. Furthermore, this encryption algorithm employs a comprehensive permutation process along with parallel bit-shift coupling, effectively transforming the image target areas into visually meaningless forms. It also separately encrypts each bit plane, enabling the encryptor to implement different decryption effects by assigning key streams with different lengths. Finally, the comprehensive performance analysis results highlight that the designed algorithm achieves a maximum information entropy value of 7.9998 in encrypted images. Moreover, its resistance to differential attacks (as measured by NPCR and UACI) and pixel correlation are infinitely close to the ideal state, significantly underscoring its security and effectiveness.

A Wireless Body Area Network (WBAN) is a network of wireless sensor nodes that can be installed inside or outside of the human body. This network is crucial in medical problems. Due to storage, battery power, and computational resource limitations, the security of medical information such as medical photographs or other information is a major concern in (WBAN). This work proposes an image encryption approach that addresses these constraints by utilizing adaptive DNA code bases and a new multi chaotic map architecture. DNA coding is used to enhances computing efficiency and gives great data transfer capabilities and the new multi chaotic map was formed by Combining Henon, Gaussian and Logistic map (HGL) To generate more chaotic pseudo-random sequences. Numerous analyses were conducted to test the proposed scheme, such as brute force, statistical, differential assaults and noise added analysis. Results indicated that this scheme has a strong level of security.

Wireless Sensor Networks (WSNs) is a collection of tiny distributed sensor nodes that have been used to sense the physical parameters of the environment where it has been deployed. Data dissemination is an important activity performed in WSNs in order to administer and manage them. Gossiping makes the network to transmit the same data item multiple times by multiple sensor nodes to their neighbors until they reach the required nodes which are in need of them. These multiple transmissions result in a problem called a Redundant Broadcast Storm Problem (RBSP). Moreover, the RBSP results in too many senders’ problem and also leads to the consumption of more energy in the network. In data dissemination, providing energy efficiency and security are the two major challenging issues. In such a scenario, the attackers may make use of the weakness in security provisions available in the network and they can perform unauthorized activities to disrupt the process of data dissemination. Hence, it is necessary to address the issues of RBSP, energy consumption, security and too many senders problem in order to enhance the reliability and security of communication in WSN for data dissemination. In this paper, a novel protocol named Cluster based Secured Data dissemination Protocol (CSDP) has been proposed for providing energy efficient and secured dissemination of data. The proposed protocol is a distributed protocol which considers the route discovery process, cluster formation, cluster head selection, cluster based routing and security through the design of a new digital signature based authentication algorithm, trust based security enhancement and encryption techniques for effective key management. The major contributions of the proposed work include the proposal of cryptography based public key and private key generation algorithms, techniques for trust score computation and malicious node identification and finally the effective prevention of malicious activities for enhancing the security of the network. Moreover, this work considers node identification techniques for effective clustering of nodes and performs optimal route discovery and secured transmission of packets. This work is novel with respect to multicast based data dissemination protocol, proposal of combined signature generation and verification schemes, encryption based key management and distributed data collection and communication techniques. In addition, an Intelligent Fuzzy based Unequal Clustering algorithm is used to perform effective clustering process and the traffic analyzer to identify the intruders by monitoring the node’s behaviors and their trust values. The proposed protocol has been extensively tested with realistic simulation parameters using NS2 simulator. The simulation results obtained from this work have proved that the proposed protocol improves the level of security through the proposal of a time efficient encryption and decryption algorithm with increase in packet delivery ratio and network throughput and at the same time it reduces the energy consumption as well as delay in data dissemination.

A symmetric key image cryptosystem based on the piecewise linear map is presented in this paper. In this cryptosystem, the encryption process and the decryption process are exactly same. They both include the same operations of plaintext-related scrambling once, diffusion twice and matrix rotating of 180 degrees four times. The length of secret key in the system is 64d where d is a positive integer. The proposed system can fight against the chosen/known plaintext attacks due to the using of plaintext-related scrambling. The simulate results and comparison analysis show that the proposed system has many merits such as high encryption/decryption speed, large key space, strong key sensitivity, strong plaintext sensitivity, strong cipher-text sensitivity, good statistical properties of cipher images, and large cipher-text information entropy. So the proposed system can be applied to actual communications.

The increased exchange of data over the Internet in the past two decades has brought data security and confidentiality to the fore front. Information security can be achieved by implementing encryption and decryption algorithms to ensure data remains secure and confidential, especially when transmitted over an insecure communication channel. Encryption is the method of coding information to prevent unauthorized access and ensure data integrity and confidentiality, whereas the reverse process is known as decryption. All encryption algorithms aim to secure data; however, their performance varies according to several factors such as file size, type, complexity, and platform used. Furthermore, while some encryption algorithms outperform others, they have been proven to be vulnerable to specific attacks. In this paper, we present a general overview of common encryption algorithms and explain their inner workings. Additionally, we select ten different symmetric encryption algorithms and conduct a simulation in Java to test their performance. The algorithms we compare are AES, BlowFish, RC2, RC4, RC6, DES, DESede, SEED, XTEA, and IDEA. We present the results of our simulation in terms of encryption speed, throughput, and CPU utilization rate for various file sizes ranging from 1MB to 1GB. We further analyze our results for all measures that have been tested, taking into account the level of security they provide.

Proxy re-encryption (PRE) is a cryptosystem that realizes efficient encrypted data sharing by allowing a third party proxy to transform a ciphertext intended for a delegator (i.e., Alice) to a ciphertext intended for a delegatee (i.e., Bob). Attribute-based proxy re-encrypftion (AB-PRE) generalizes PRE to the attribute-based scenarios, enabling fine-grained access control on ciphertexts. However, the existing AB-PRE schemes do not adequately address the following problems: (1) the risk of decryption key leakage, and (2) the need of time-based delegation. To resolve these problems, we introduce a primitive called time-based attribute-based proxy re-encryption (TB-AB-PRE) with decryption key update. TB-AB-PRE associates keys with the current time information and supports efficient periodical decryption key update for each time transition. This property guarantees that a compromise of a decryption key for some time does not breach the security of ciphertexts from the others. Leveraging this time-based property, the proposed TB-AB-PRE elegantly achieves time-based delegation which enables Alice to decide which ciphertexts can be transformed and their decryptable timeframe after being transformed. The proposed construction is proven to be secure against honest re-encryption attacks with decryption key exposure resistance, under the learning with errors assumption.

With the growing number of cloud users, shared data auditing is becoming increasingly important. However, these schemes have issues with the certificate management. Although there is a certificate-shared auditing scheme, it is ineffective in dealing with dynamic data and protecting data privacy. The verifier cannot access the data content to ensure data integrity due to security concerns. This paper proposes a novel technique to ensure the integrity and improve the access control. A novel enhanced storage retrieval mechanism is used to improve the performance of the cloud’s storage and retrieval mechanisms to achieve this. The technique is evaluated in concern of the upload, download, encryption, and decryption time. As the file size grows, so does the time it takes to upload it. Similarly, the time taken to encrypt files of various formats and sizes evidenced that it depends on the file size and format. Thus, the encryption time increases as the file sizes increases, demonstrating the performance of the proposed system.

During medical picture transmission, the most pressing concern is security. Medical images must be encrypted since they are extremely sensitive. Watermarking, digital fingerprinting/signature, and encoding are some of the available image security techniques. Images and movies, for example, must be highly encrypted and decoded without losing any content information. Medical photos, for example, require extra protection, and protecting medical images is a critical issue when medical images and related patient information are transferred over public networks. This research work proposes a visual encryption strategy to secure medical pictures before being transmitted or stored in the cloud. This technique makes such pictures of unauthorized people unavailable and also maintains confidentiality, a prime safety requirement. The process made use of a pixel shuffling-based encryption technique and a secret key created from the image. In this research, we encrypted the medical image using modified Arnold Map Encryption and generated secret key values. Therefore, the image is encrypted, and henceforth it is decrypted as well. So this work gave us the encrypted image and decrypted image/original image as well. The modified Arnold Map Encryption tries to add more randomness, thus increasing the entropy of the image and thus makes it harder to decrypt. The modified Arnold Map Encryption is also compared to other algorithms such as Hyper Chaotic, Secure Hash Algorithm-13 (SHA-13), Ten Logistic Maps, Bakers Map, HenonMap, Cross Chaos Map, and 2D Logistic Map and shows better results in terms of encryption speed and Number of Pixel Change Rate (NPCR) value.