Dynamic Encryption Research Articles

Encoding Coacervate Droplets with Paramagnetism for Dynamical Reconfigurability and Spatial Addressability.

It is an ongoing endeavor in chemistry and materials science to regulate coacervate droplets on a physiologically relevant spatiotemporal scale to ultimately match or even surpass living cells' precision, complexity, and functionality. Herein, we develop a magnetic strategy orthogonal to the thermal, pH, light, or chemical counterparts that are commonly employed by biotic or artificial systems; its successful implementation thus adds a missing piece to the current arsenal of manipulative methodologies. Specifically, we paramagnetize the otherwise diamagnetic coacervate droplets by cooperatively combining paramagnetic ingredients (including organic radicals, metal ions, and Fe3O4 nanoparticles) and coacervate ingredients to obtain "MagCoa" droplets. A simple model is derived theoretically to account for migration and division of MagCoa droplets in an uneven magnetic field. Experimentally, we produce an array of compartmentalized and monodispersed droplets using microfluidics and magnetically steer them with uniformity and synchronicity. We design and fabricate spatial magnetic modulators to engineer the landscape of a magnetic field that, in turn, directs the MagCoa droplets into predesigned patterns in a reconfigurable fashion. These programmable liquid patterns can be potentially extended to dynamic assembly and information encryption. We envision that the toolbox established here is of generality and multitudes to serve as a practical guide to control droplets magnetically.

One stimulus-induced two-step photophysical response with high contrast and tunable switching time for dynamic displaying

One stimulus-induced two-step photophysical response, especially with tunable switching time, is a great challenge for organic chromophores. Herein, a polymorphic material 2,7-DCF could undergo in situ two sequential dual-channel responses upon dichloromethane fuming. Both the appearance color and the fluorescence change from red to yellow to deep red with high contrast. The first step corresponds to a fast amorphous-to-crystalline transformation, while the second is a slow solid-state cocrystallization process. Based on single crystal structures and theoretical calculations, such distinct color changes are mainly attributed to conformation twisting and the electron coupling with incorporated solvent molecule through C-H⋅⋅⋅O interaction. Importantly, the second slow photophysical response could be drastically sped up by seeding strategy, or be totally inhibited. Such characteristics pave a way for the potential applications in dynamic anti-counterfeiting and data encryption. Based on the two-step transformation, polymorph 2,7-DCF-a could achieve a successive four-level response to external stimuli. In contrast, polymorph 2,7-DCF-d exhibits a stepwise hypsochromic fluorescence shift over 100 nm. This study would significantly promote the development of stimuli-sensitive systems from “one stimulus, one-step response” to “one stimulus, two or multi-step response”.

A Novel Chaotic Image Encryption Scheme Armed with Global Dynamic Selection

Due to the equivalent keys revealed by a chosen-plaintext attack or a chosen-ciphertext attack, most of the existing chaotic image encryption schemes are demonstrated to be insecure. In order to improve security performance, some scholars have recently proposed the plaintext-related chaotic image encryption scheme. Although the equivalent effect of a one-time pad is achieved, an additional secure channel is required to transmit the hash values or other parameters related to the plaintext before the ciphertext can be decrypted at the receiving end. Its main drawback is that an absolutely secure channel is needed to transmit the information related to the plaintext, which is not feasible in practical applications. To further solve this problem, this paper proposes a chaotic image encryption scheme based on global dynamic selection of a multi-parallel structure. First, a chaotic sequence is employed to dynamically select DNA encoding rules. Secondly, the permutation with a multi-parallel structure is performed on the DNA-encoded matrix, and the DNA decoding rules are dynamically selected according to another chaotic sequence. Finally, the diffusion rules obtained by the ciphertext feedback mechanism are introduced to determine the dynamic diffusion. Compared with the existing local dynamic encryption schemes, the main advantage of this scheme is that it can realize global dynamic selection, so as to ensure that there is no equivalent key, and it can resist the chosen-ciphertext attack or chosen-plaintext attack and does not need an additional secure channel to transmit parameters related to plaintext, which is practical. A theoretical analysis and numerical experiments demonstrate the feasibility of the method.

Photoexcitation-Induced Assembly: A Bottom-Up Physical Strategy for Driving Molecular Motion and Phase Evolution

ConspectusIn the field of molecular assembly, photodriven self-assembly is a smart and crucial strategy to regulate the molecular orderliness, multiscale structure, and optoelectronic properties. Traditionally, photodriven self-assembly is based on photochemical processes, through molecular structural change induced by photoreactions. Despite great progress in the photochemical self-assembly, there still exists disadvantages (e.g., the photoconversion rate never reaches 100% with the possible side reactions). Therefore, the photoinduced nanostructure and morphology are often difficult to predict due to insufficient phase transition or defects. In contrast, the physical processes based on photoexcitation are straightforward and can fully utilize photons to avoid the drawbacks of photochemistry. The photoexcitation strategy excludes the change of molecular structure, only utilizing the molecular conformational change from the ground state to excited state. Then, the excited state conformation is employed to drive molecular movement and aggregation, further promoting the synergistic assembly or phase transition of the entire material system. The regulation and exploration of molecular assembly upon photoexcitation can open up a new paradigm to deal with the "bottom-up" behavior and develop unprecedented optoelectronic functional materials.This Account starts with a brief introduction to the problems faced by photocontrolled self-assembly and presents the photoexcitation-induced assembly (PEIA) strategy. Then, we focus on exploring PEIA strategy based on persulfurated arenes as the prototype. The molecular conformational transition of persulfurated arenes from the ground state to the excited state is conducive to the formation of intermolecular interactions, successively driving molecular motion, aggregation, and assembly. Next, we describe our progress in exploring PEIA of persulfurated arenes at the molecular level and then demonstrate that the PEIA of persulfurated arenes can synergistically drive molecular motion and phase transition in various block copolymer systems. Moreover, we provide the potential applications of PEIA in dynamic visual imaging, information encryption, and surface property regulation. Finally, an outlook on further development of PEIA is prospected.

Dynamic Multimedia Encryption Using a Parallel File System Based on Multi-Core Processors

Securing multimedia data on disk drives is a major concern because of their rapidly increasing volumes over time, as well as the prevalence of security and privacy problems. Existing cryptographic schemes have high computational costs and slow response speeds. They also suffer from limited flexibility and usability from the user side, owing to continuous routine interactions. Dynamic encryption file systems can mitigate the negative effects of conventional encryption applications by automatically handling all encryption operations with minimal user input and a higher security level. However, most state-of-the-art cryptographic file systems do not provide the desired performance because their architectural design does not consider the unique features of multimedia data or the vulnerabilities related to key management and multi-user file sharing. The recent move towards multi-core processor architecture has created an effective solution for reducing the computational cost and maximizing the performance. In this paper, we developed a parallel FUSE-based encryption file system called ParallelFS for storing multimedia files on a disk. The developed file system exploits the parallelism of multi-core processors and implements a hybrid encryption method for symmetric and asymmetric ciphers. Usability is significantly enhanced by performing encryption, decryption, and key management in a manner that is fully dynamic and transparent to users. Experiments show that the developed ParallelFS improves the reading and writing performances of multimedia files by approximately 35% and 22%, respectively, over the schemes using normal sequential encryption processing.

Dynamic anti-counterfeiting and information encryption of Sr3Y2Ge3O12: Tb3+, Er3+ phosphor via carriers filling and release processes

Complex and high-security-level anti-counterfeiting strategies with multiple luminescent modes are extremely critical for meeting the requirement of constantly developing information storage and information security. In this work, Tb3+ ions doped Sr3Y2Ge3O12 (SYGO) and Tb3+/Er3+ co-doped SYGO phosphors are successfully fabricated and are unitized for anti-counterfeiting and information encoding under distinct stimuli sources. The green photoluminescence (PL), long persistent luminescence (LPL), mechano-luminescence (ML), and photo-stimulated luminescence (PSL) behaviors are respectively observed under the stimuli of ultraviolet (UV), thermal disturbance, stress, and 980 nm diode laser. Based on the time-dependence of the filling and releasing rate of the carriers from the shallow traps, the dynamic information encryption strategy is proposed by simply changing the UV pre-irradiation time or shut-off time. Moreover, a tunable color from green to red is realized by prolonging the 980 nm laser irradiation time, which is attributed to the elaborate cooperation of the PSL and upconversion (UC) behaviors. The anti-counterfeiting method based on SYGO: Tb3+ and SYGO: Tb3+, Er3+ phosphors herein possess an extremely high-security level with attractive performance for designing advanced anti-counterfeiting technology.

A dynamic encryption–decryption scheme for replay attack detection in cyber–physical systems

This paper deals with the replay attack detection problem for a class of cyber–physical systems. A dynamic encryption–decryption scheme is proposed with the purpose of detecting the replay attacks launched by the malicious adversary. First, a new attack model is established to describe the periodic replay attacks that are generated by making use of a series of recorded past measurements. Then, the stealthiness is discussed for the proposed replay attack scheme against the χ2 detector. Subsequently, on basis of the established model, a dynamic encryption–decryption scheme is developed without sacrificing any system performance, guaranteeing 100% detection probability in the occurrence of attacks. Finally, a simulation example is provided to firstly verify the stealthiness of the proposed replay attack and secondly demonstrate the effectiveness of the exploited dynamic encryption–decryption detection algorithm.

A Searchable Encryption with Forward/Backward Security and Constant Storage

Dynamic searchable encryption satisfies users’ needs for ciphertext retrieval on semi-trusted servers, while allowing users to update server-side data. However, cloud servers with dynamically updatable data are vulnerable to information abuse and file injection attacks, and current public key-based dynamic searchable encryption algorithms are often complicated in construction and high in computational overhead, which is not efficient for practical applications. In addition, the client’s storage costs grow linearly with the number of keywords in the database, creating a new bottleneck when the size of the keyword set is large. To solve the above problems, a dynamic searchable encryption scheme that uses a double-layer structure, while satisfying forward and backward security, is proposed. The double-layer structure maintains a constant client-side storage cost while guaranteeing forward and backward security and further reduces the algorithm overhead by avoiding bilinear pairings in the encryption and decryption operations. The analysis results show that the scheme is more advantageous in terms of security and computational efficiency than the existing dynamic searchable encryption scheme under the public key cryptosystem. It is also suitable for the big data communication environment.

A remote sensing encrypted data search method based on a novel double-chain

Remote sensing is considered to be a key technology for the development of smart cities. By analysing the data obtained by remote sensing, it is effective to manage and develop smart cities. However, with the rapid urbanisation and the increase in data capacity, how to store and retrieve remote sensing data which have more potential value and privacy with a more effective and safe method has become an imminent issue. In this paper, we propose an efficient verifiable and dynamic multi-keyword searchable encryption scheme for remote sensing data in smart cities. Moreover, we construct a double-chain index to support a multi-keyword search, where the Verification Index Chain is used to identify the users and the Keyword Index Chain is used to store the information of keywords. In addition, we adopt extended bitmap technology to realise update operations and verify the correctness and integrity of the search results. Experiments show that compared to the related existing schemes, the search time of the proposed scheme is reduced by 35% at most, the verification time is reduced by 14% at most and the update time is reduced by 57% at most.

SEOT: Secure dynamic searchable encryption with outsourced ownership transfer

SEOT: Secure dynamic searchable encryption with outsourced ownership transfer

Deep learning based energy efficient optimal RMC-CNN model for secured data transmission and anomaly detection in industrial IOT

As we know that the generated data from the million sensors in Industrial Internet of Things (IIoT) is tremendously heterogeneous, large, & dynamic. This, in turn, poses a significant demand on the decision making and real-time analysis for detection of an anomaly in IIoT. In this paper, an effective scheme for energy efficient secured data transmission is presented for outlier detection in IIoT. The main intention of this approach is to offer a secure and privacy preserved data transmission scheme in industrial IoT. For this, industrial data like power, loop sensor, and the land sensor is taken as input, and the system network model is created which is then optimized with the use of Multi-scale grasshopper optimization scheme. Then the data is stored in the cloud and is transmitted in a secured manner. For this purpose, the attack detection in the network is made using Robust Multi-cascaded CNN (RMC-CNN) classification approach to distinguish the type of attack. Then the data is encrypted by key generation mechanism using a dynamic honey pot encryption algorithm. Thus, the encrypted information is transmitted securely and is stored in the IoT cloud, which can be decrypted as per user request. The performance analysis is made and is compared with existing techniques in term of accuracy, precision, recall, and F1-score for power, loop sensor and land sensor dataset. And also, the comparison is made for throughput, delay, and detection rate analysis. Finally, the encryption, decryption and execution time is estimated and are compared with existing techniques. The study shows that the proposed system achieves a better outcome for the proposed system than the existing methods.

Multi-User Dynamic Searchable Symmetric Encryption With Corrupted Participants

We study the problem of multi-user dynamic searchable symmetric encryption (DMUSSE) where a data owner stores its encrypted documents on an untrusted remote server and wishes to selectively allow multiple users to access them by issuing keyword search queries. Specifically, we consider the case where some of the users may be corrupted and <i>colluding with the server</i> to extract additional information about the dataset (beyond what they have access to). We provide the first formal security definition for the dynamic setting as well as forward and backward privacy definitions. We then propose <inline-formula><tex-math notation="LaTeX">$\mu$</tex-math></inline-formula> <small>SE</small> , the first provably secure DMUSSE scheme and instantiate it in two versions, one based on oblivious data structures and one based on update queues, with different performance trade-offs. Furthermore, we extend <inline-formula><tex-math notation="LaTeX">$\mu$</tex-math></inline-formula> <small>SE</small> to support verifiability of results. To achieve this, users need a secure digest initially computed by the data owner and changed after every update. We efficiently accommodate this, without relying on a trusted third party, by adopting a blockchain-based approach for the digests’ dissemination and deploy our schemes over the permissioned Hyperledger Fabric blockchain. We prototype both versions and experimentally evaluate their practical performance, both as stand-alone systems and running on top of Hyperledger Fabric.

Time-Based Steganography Image with Dynamic Encryption Key Generation

The rapid advancement of technology has necessitated stronger protection measures for data exchange. Encryption, coupled with robust keys, is an effective method to safeguard sensitive information. This study aims to improve the security of key levels by implementing a combination of steganography and encryption. The approach involves using two keys, one in the form of a normal string and the other based on the insertion time. These keys are combined to create a new, stronger encryption key. The secret messages are then encrypted using this new key and inserted using the Least Significant Bit method in steganography. This integrated approach aims to provide a higher level of protection for data during transmission and storage.

Sophisticated yet Convenient Information Encryption/Decryption Based on Synergistically Time-/Temperature-Resolved Photonic Inks.

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.

Thermally Induced Reversible Fluorescence Switching of Lead Chloride Hybrids for Anticounterfeiting and Encryption.

Metal halide hybrids with thermally induced fluorescence transition have the potential to be utilized as the next generation of smart materials in optoelectronic devices. However, the fabrication of thermochromic materials with simultaneously reversible and lower transition temperatures is still a challenge. Herein, we present a novel one-dimensional (1D) organic-inorganic lead chloride hybrid (TPA)PbCl3-Green (TPA = tetrapropylammonium) single crystal that exhibits green emission and up to 30% photoluminescence quantum yield (PLQY). It is worth noting that the (TPA)PbCl3-Green crystal changes emission from green to blue light when heated at 323 K. The emission spectra indicate that the blue light is attributed to the combination of two emission peaks located at 438 and 520 nm, respectively. Furthermore, the green luminescence is restored after natural cooling to room temperature. The dynamic transition process is demonstrated via steady-state photoluminescence, single-crystal X-ray diffraction (SCXRD), and powder X-ray diffraction (XRD). (TPA)PbCl3-Green crystals and (TPA)PbCl3-Green@PVP complexes have also been explored as fluorescent security inks for dynamic anticounterfeiting and message encryption as well as optical logic gate applications due to the excellent cycling stability and low transition temperature. This material offers a completely new option for thermochromic materials used for security information.

A Novel Smart Home Lightweight Authentication Protocol using IoT Applications

The Internet of Things (IoT) introduces innovative real-time applications that use sensors to collect data that exchange between things to things and things to humans through the network. In this aspect, security and privacy is the primary concern for researchers to protect these systems. This paper proposes a real-time authentication algorithm based on the one-time pad (OTP) principle. The keys are dynamically exchanged, and the data is encrypted via dynamic encryption, depending on random sensors’ data. The key is generated and exchanged dynamically using the dynamic encryption technique, thus enhancing the users’ data privacy and security. Moreover, a lightweight key generation, exchange, and authentication protocol are proposed for data collecting from smart home sensors. The proposed protocol guarantees security and privacy demand, which are the user’s primary concern. The proposed protocol is developed for smart home applications with interfacing requirements, which makes the system real and applicable. The operation principle of the proposed protocol is illustrated sufficiently if there is any desynchronization or emergency.

Blockchain-based verifiable and dynamic multi-keyword ranked searchable encryption scheme in cloud computing

Rational miners in the blockchain may admit the validity of search results directly to conserve calculation overhead without executing the validation. Such phenomenon is known as the Verifier's Dilemma that the search results of the blockchain-based searchable encryption scheme would be claimed to have been verified but devoid of valid verification. Besides, the top-k query technique utilized by most existing searchable encryption schemes fails to filter the search results from the user demands during retrieval, which results in massive ineffective access lists with high complexity. Aiming at the two problems, we present a blockchain-based multi-keyword ranked searchable encryption scheme and design a fair payment protocol for multi-user scenarios. Our scheme may achieve public verifiability and user fairness by leveraging the TrueBit network, while the data owner (DO) can withdraw search privileges from the authorized data user (DU). Also, we extend the searchable encryption scheme based on inverted index to multi-DO/multi-DU scenarios, and the HashMap index is used to diminish the response time and space complexity. Moreover, the proposed scheme supports the update of index keywords and files dynamically. To enhance retrieval accuracy, we modify the information divergence algorithm in machine learning and utilize the monotonically weighted aggregation function, which improves retrieval accuracy to around 97%. Finally, Security analysis illustrates correctness and resilience against typical attacks to verify the robustness and utility of the proposed scheme.

CEaaS: Constrained Encryption as a Service in Fog-Enabled IoT

In this work, we present a solution toward facilitating dynamic encryption schemes—Constrained Encryption as a Service (CEaaS)—in fog-enabled IoT environments. CEaaS is a two-level fuzzy inference system (FIS) in the fog layer which offers customized encryption algorithm decisions to the IoT user devices based on the current configuration, data size, and network state. Fog nodes use the two-tier FIS system to determine the category of the requesting IoT device at the first level and then the encryption scheme at the second level. Existing research on encryption focuses on developing new lightweight algorithms as a global solution for all devices without considering the heterogeneity and corresponding communication links. The device and network configurations collectively add operational delays, which elevates time and security threats. Under such circumstances, a solution that considers both the conditions (varying) for determining the appropriate encryption scheme and the key is important. Through extensive implementation and deployment of heterogeneous fog nodes, we observe that CEaaS is feasible for both powerful and resource-constrained IoT user devices with CPU and memory usage as low as 0.24% and 0.9%, respectively. CEaaS also incurs delays in the range of 0.7 s and energy consumption of 0.07 Joules while securing data transmission. With the feasibility of CEaaS, the dynamic encryption schemes ensure secure communications irrespective of the device types in a fog-enabled IoT environment.

Photostable and printable fluorescence carbon quantum dots for advanced message encryption and specific reversible multiple sensing of Cu2+ and cysteine

The ability to manipulate carbon quantum dots (CQDs) fluorescence with specific substances has been of primary importance for applications in advanced dynamic information encryption. The development of CQDs with specific functionalization, high selectivity and excellent fluorescence stability for information security and sensing remains a challenge. In this paper, we present an N-doped and tryptophan functionalized CQDs that can be applied not only as a fluorescent ink for multiple message encryption but also for fluorescent sensitive and selective recognition of Cu2+ and cysteine (Cys) by multi-method, including aqueous solutions, filter paper, hydrogels and in human DU-145 Prostate cancer cells. Theoretical calculations and mechanistic studies suggested that this on–off-on mechanism was attributed to the transfer of electrons between Cu2+ and functionalized groups on the surface of CQDs and stronger coordination capability with Cys. The above results showed that these newly designed CQDs will greatly enrich the fundamental understanding of CQDs by explaining the recognition mechanism between Cu2+ and Cys, and provide an opportunity for anti-counterfeiting, solid-state fluorescent materials, cellular imaging and environmental.

A Secure Personal Health Record Sharing System with Key Aggregate Dynamic Searchable Encryption

Recently, as interest in individualized health has increased, the Personal Health Record (PHR) has attracted a lot of attention for prognosis predictions and accurate diagnoses. Cloud servers have been used to manage the PHR system, but privacy concerns are evident since cloud servers process the entire PHR, which contains the sensitive information of patients. In addition, cloud servers centrally manage the PHR system so patients lose direct control over their own PHR and cloud servers can be an attractive target for malicious users. Therefore, ensuring the integrity and privacy of the PHR and allocating authorization to users are important issues. In this paper, we propose a secure PHR sharing system using a blockchain, InterPlanetary File System (IPFS), and smart contract to ensure PHR integrity and secure verification. To guarantee the patient’s authority over the management of his/her own PHR, as well as provide convenient access, we suggest a key aggregate dynamic searchable encryption. We prove the security of the proposed scheme through informal and formal analyses including an Automated Verification of Internet Security Protocols and Applications (AVISPA) simulation, Burrows–Abadi–Needham (BAN) logic, and security-model-based games. Furthermore, we estimate the computational costs of the proposed scheme using a Multiprecision Integer and Rational Arithmetic Cryptographic Library (MIRACL) and compare the results with those of previous works.