Avalanche Effect Research Articles

Encryption Based on Cellular Automata for Wireless Devices in IoT Environment

A large number of physical objects are interconnected and accessed through the internet along with the existing technology like cloud computing, mobile computing, wireless sensor networks and big data forms a big paradigm called the Internet of Things (IoT). Data from remote and neglected areas are collected via wireless sensors and stored in the cloud. Growth in the number of the sensing device and the server to which these are connected leads to many security issues and malicious attacks. With mirai botnet and jeep hack about 150 million user’s information from MyFitnessPal nutrition app was stolen. This paper mainly focuses on security challenges for transmitting the data in the wireless sensor network in the IoT environment. To avoid the malicious attack, eavesdropping, algebraic attacks and other attacks a new security algorithm is proposed based on Cellular Automata (CA) which has a key length of 80 bits and the text size is 64 bits. Reversible rules of CA are used in this algorithm to achieve reversibility, parallelism, stability, randomness, and uniformity. The process of encryption and decryption is performed for 15 rounds to avoid dependency between the ciphertext and the plain text. Finally, we compare the execution time, throughput and the avalanche effect of the proposed algorithm with the existing algorithm like Advanced Encryption Standard (AES), Height, Present algorithm. The proposed algorithm is verified to be a better choice for lost cost and resource-restricted devices.

Performance Analysis of Cascaded Hybrid Symmetric Encryption Models

Over a few years, there is rapid increase of exchange of data over the net has brought data confidentiality and its privacy to the fore front. Data confidentiality can be achieved by implementing cryptography algorithms during transmission of data which confirms that data remains secure and protected over an insecure network channel. In order to ensure data confidentiality and privacy, cryptography service encryption is used which makes data in unreadable form while the reverse process rearranges data in readable form and known as decryption. All encryption algorithms are intended to provide confidentiality to data, but their performance varies depending on many variables such as key size, type, number of rounds, complexity and data size used. In addition, although some encryption algorithms outperform others, they have been found to be prone to particular attacks. This paper reviews and summarizes the various common hybrid cascaded n-tier encryption models. Additionally, this paper compares and analyzes the performance of common hybrid cascaded 2-tier and 3-tier encryption models obtained during simulation based on encryption/decryption time, avalanche effect and throughput. The models compared with AES are 2-tier models (AES-TWOFISH, AES-BLOWFISH, TWOFISH-AES, BLOWFISH-AES, AES-SERPENT and SERPENT-TWOFISH) and 3-tier models (DES-BLOWFISH-AES, AES-TWOFISH-SERPENT and SERPENT-TWOFISH-AES). The hybrid cascaded model like AES-TWOFISH, AES-BLOWFISH and SERPENT-TWOFISH-AES are better hybrid models with respect to throughput and avalanche effect.

Image Encryption Using RK-RSA Algorithm in Aadhaar Card

Cryptography is used for secretly sending information. The information or given data is protected by cryptographic technique. The technique is used in Text and images. The technique is supported by a lot of algorithms. RSA is a better encryption technique for smart cards. In this paper, an image in the Aadhaar card is encrypted using the RK-RSA algorithm for better protection and confidentiality. The proposed RK-RSA algorithm is very secure for smart cards and Aadhaar cards. The better performance of the RK-RSA is evaluated based on the Avalanche Effect, Speed, Throughput, and Power Consumption. The improved performance of the RK-RSA algorithm’s experimental results is reported. The mathematical justification supporting the RK-RSA algorithm is also detailed.

Asymmetric DNA encryption and decryption technique for Arabic plaintext

The security of transmitting information from one point to another through different media is an important issue in the modern digital society. Researchers have consistently developed and proposed modern data transfer systems in order to transfer data in a safe manner. DNA (deoxyribonucleic acid) based encryption technology is a new encryption model used to protect data during transmission. Current systems that use DNA technology to encrypt Arabic texts are virtually non-existent and intended to hide data rather than encrypting it (i.e., steganography). In this research, an asymmetric DNA encryption technology is offered to encrypt and decrypt simple Arabic scripts. This technology depends on the integrity between asymmetric cryptography (i.e. RSA algorithm), dynamic encoding, and data dependency with the scope of DNA computing technology. Asymmetric cryptosystem is used only to begin the process of encryption and decryption, which is then processed fully using DNA computing. The idea of the proposed algorithm aims to generate a dynamic DNA table that depend on plain text, that aims to generate a dynamically generating 14 circular keys based on a multi-level security. Here, JAVA platform is used to implement the proposed work, and the randomization and avalanche effect are used to prove the efficiency of the proposed algorithm. This technique provides a significant change in the encoded text with an average of 53% of the avalanche characteristic.

Improvement of RSA Algorithm Using Euclidean Technique

Information Security has become an essential concern in the modern world. Encryption is an effective way to prevent an unofficial person from viewing the digital information with the secret key. RSA encryption is often used for digital signatures which can prove the authenticity and reliability of a message. As RSA encryption is less competent and resource-heavy, it is not used to encrypt the entire message. If a message is encrypted with a symmetric-key RSA encryption it will be more efficient. Under this process, only the RSA private key will be able to decrypt the symmetric key. The Euclidean algorithm is attainably one of the most extensively known algorithms. The Euclidean algorithm is used for finding the greatest common divisor of two numbers. The algorithm can also be defined for more general rings than just the integers. This work is very useful to improve the data security in Smart card and Aadhaar card. In this paper, the RSA algorithm is modified using the Euclidean technique to improve its performance. The proposed algorithm shows its better performance in terms of speed, throughput, power consumption, and the avalanche effect. Experimental results and mathematical justification supporting the proposed method are reported.

Active control of terahertz waves based on p-Si hybrid PIT metasurface device under avalanche breakdown.

Active control of terahertz waves is a critical application for terahertz devices. Silicon is widely used in large-scale integrated circuit and optoelectronic devices, and also shows great potential in the terahertz field. In this paper, a p-Si hybrid metasurface device is proposed and its terahertz characteristics under avalanche breakdown effect is investigated. In the study, a plasmon-induced transparency (PIT) effect caused by the near-field coupling of the bright mode and the dark mode is observed in the transmission spectrum. Due to avalanche breakdown effect, the resonance of the PIT metamaterial disappears as the current increased. Carriers existed in the interface between the metasurface and substrate result to a dipole resonance suppression. When the current continues increasing, the maximal modulation depth can reach up to 99.9%, caused by the avalanche effect of p-Si. Experimental results demonstrate that the avalanche breakdown p-Si can achieve a performance modulation depth, bringing much more possibilities for terahertz devices.

A Dynamic Load Balancing Strategy Based on Improved Ant Colony Algorithm

Load balancing technique plays a fundamental role in distribution, while facing numerous challenges. It is difficult for ordinary load algorithms to cope with complex scenarios, and it is likely that uneven load will lead to downtime of a single server, thus causing an avalanche effect and eventually breaking down the whole cluster. This paper proposes a load balancing strategy based on improved ant colony algorithm, considers the influence of task length and processing efficiency in the algorithm based on the original ant colony algorithm, and takes the load rate of nodes as an important index for ants to select path. In addition, the load coefficient includes CPU, memory, IO, and network bandwidth into the calculation range, which makes the obtained server load condition more accurate. Finally, test data of different algorithms are obtained through experiments, and the advantages and disadvantages of this load balancing strategy are verified after horizontal comparison.

Analytical model for the inductive turn-off process of GCT with dynamic avalanche

Dynamic avalanche injection during the turn-off of the gate commutated thyristors (GCTs) can slow down the removal of the remaining carriers, thereby affecting the turn-off characteristics. In addition, it is also a key factor inducing the turn-off failure of the device. However, the analytical model for the turn-off process considering dynamic avalanche effect has been not developed so far. In this paper, the turn-off process is divided into two phases, without dynamic avalanche and with dynamic avalanche, to be analyzed while assuming the appearance of the electron current in the space charge region of the P base/N- drift junction as the initial condition of occurrence of dynamic avalanche. As a result, a one-dimensional (1-D) physics-based analytical model is derived based on the basic principles of semiconductor and it gives insight into the details of internal physical mechanisms of the GCTs when dynamic avalanche occurs. And the analytically calculated results obtain a good agreement with the numerical simulations on the whole. It is also revealed that the avalanche-generated current filament is the main reason causing the difference between the 1-D analytical model and the two-dimensional (2-D) numerical simulation.

Shadow: A Lightweight Block Cipher for IoT Nodes

The advancement of the Internet of Things (IoT) has promoted the rapid development of low-power and multifunctional sensors. However, it is seriously significant to ensure the security of data transmission of these nodes. Meanwhile, sensor nodes have the characteristics of converting analog signals into digital signals for operation processing in wireless sensor networks (WSNs). Given the particularity of Addition or AND, Rotation, and XOR (ARX) operations, its round function can only be based on the Feistel structure or generalized Feistel structure, otherwise, the process of decryption cannot be completed correctly. Furthermore, the existing ARX ciphers have the problems of only changing half of the plaintext block in one round and iterating for many rounds. In this article, a new logical combination method of generalized Feistel structure and ARX operations is proposed to improve the diffusion speed of ARX ciphers, called Shadow. Shadow overcomes the shortcomings of traditional ARX ciphers that only diffuse half of the block in one round. To ensure the efficiency of the encryption hardware circuit while ensuring the security of the physical-layer signal, we studied the round-based hardware architecture and the serial hardware architecture for Shadow cipher. Particularly, we conducted a series of performance tests on Shadow, including the avalanche effect, FPGA implementation, and ASIC implementation. Also, we conducted a security analysis of the Shadow. As shown by our experiments and comparisons, Shadow is compact in IoT nodes and is of high security against cryptanalysis.

Development and Climate Change Contribute to a Himalayan Tragedy

Infrastructure projects like roads and dams destabilize slopes and compound the effects of glacial floods and avalanches, scientists say.

Re-Evaluation of the Security of a Family of Image Diffusion Mechanisms

In recent years, the use of permutation-diffusion architecture for digital image encryption has become increasingly popular. The permutation procedure scrambles the pixel locations, while the diffusion phase modifies the pixel values and gives rise to the avalanche effect. Various diffusion techniques have been developed, and their strength strongly impacts the security of the overall cryptosystem. In this paper, we re-evaluate the security of a family of image diffusion mechanisms that are based on mixing modulo addition with bitwise exclusive OR operations. The recovery of the encryption element of these diffusion mechanisms is comprehensively demonstrated, and the accuracy bounds under various conditions are proved mathematically. Compared to the state-of-the-art methods, our work improves the recovery accuracy of the encryption element while the required prior knowledge is decreased. The proposed analysis of the diffusion mechanisms is further used to cryptanalyze the whole cryptosystem theoretically and experimentally.

Secure Data Provenance in Internet of Things using Hybrid Attribute based Crypt Technique

In the new era of digital technology, various new applications are developed every day based on Internet of Things where the devices are interconnected between them. When the application based on IoT are used for transferring sensitive and critical data then adequate amount of confidentiality and privacy is needed also dependability is developed based on the assurance and verification of correctness and integrity of the data used. In order to address these necessary requirements of the system, Internet of Things system could be provided with data ownership and mechanisms of data provenance to maintain the data on lineage. However, to make IoT systems dependable and secure, the data provenance has to be protected sufficiently against unauthorized access and tampering of data. In this paper, a framework is proposed to secure the data provenance in Internet of Things systems using blockchain and access control policies. This work is implemented with hybrid attribute based encryption and the results are analyzed based on computational cost and throughput of encryption and decryption and also strength of the key is calculated according to avalanche effect. The experimental results prove that the proposed system is with reduced computational cost, high throughput. Setup time cost and secret key time cost are analyzed based on the access control policy tree depth. Key generation time is analyzed based on number of users. Decryption time cost is analyzed based on the no. of attributes to be decrypted. Ciphertext file size is analyzed based on the length of the plain text. According to the avalanche effect, the calculated strength of the key is good and above 99%.

Avalanche Effect and High External Quantum Efficiency in MgZnO/Au/ZnO Sandwich Structure Photodetector

AbstractThe metal–semiconductor–metal (MSM) structure is widely applied in photodetectors (PDs) owing to its simple preparation method and a more effective light collecting area. However, the realization of weak light detection remains a daunting challenge, attributed to the low external quantum efficiency (EQE) in MSM‐based PDs. Herein, sandwich structure PD (SSPD), a new structure of PD based on MSM structure, is presented to solve the problem of low gain in MSM PDs. Herein, the high‐EQE MgZnO/Au/ZnO SSPD with avalanche effect is reported for the first time. The avalanche effect is realized by changing the position of electronic transmission through energy band engineering between MgZnO and ZnO in the sandwich structure. The SSPD exhibits high EQE when photogenerated carriers get transported at the interface of ZnO and MgZnO. Under 275 nm illumination, the MgZnO/Au/ZnO SSPD achieves avalanche multiplication at 63 V and shows EQE of up to 502780% at 90 V. These results reveal that a high EQE originates from the special sandwich structure existing in MgZnO/Au/ZnO SSPD. This study presents possible guidance for high‐performance ZnO‐based avalanche PD for applications in telecommunications, sensing, and single‐photon detection.

Abnormal Strain Induced by Heavy Rainfall on Borehole Strainmeters Observed in Taiwan

We found some obvious abnormal strain induced by heavy rainfall from borehole strainmeters deployed in Western Taiwan. The strain induced by rainfall can be divided into two parts, one is the quick response for extra loads of rainwater on the ground, and another one is the slow response for rainwater infiltrating into the strata. The quick and slow rainfall responses of areal strain data are analyzed using the technique of recursive digital filtering. Moreover, the rainfall impact functions of the studied stations are calculated using deconvolution. We found, in most cases, the response strain will reach the maximum in half an hour after heavy rainfall, and then show an exponential decay, it might persist more than 200 h depending on the hydrogeological condition around the station. Whereas the river flowing beside the station will help accelerating the runoff dispersion and reducing rainfall decay time in the hill or mountain region. We also compare the results after calibration in term of isotropic and vertical coupling individually. We found that the response strains are smaller in vertical coupling rather than isotropic coupling. The effects of debris avalanches caused by intensive rainfall in the mountain areas can be viewed as two types of rock deformation: generated only under the influence of rainfall and generated by the increased load in the river channels due to rainfall-induced landslides or debris flow. When the cumulative rainfall exceeds a certain threshold, the strain response curves show a noticeable anomaly likely due to the effects of the debris flow events in places prone to landslides.

Enhanced AES algorithm based on 14 rounds in securing data and minimizing processing time

Computer, Internet technology have grown exponentially, and constant evolution until today. The usage of digital data such as text, images, audio, animation and videos are commonly used in many aspects of daily activity. The continuous increase in the use of digital data transmission over a network and it exposed to the various kinds of attacks, unauthorized access and network hacking. Thus, it is very hard to ensure that the digital data transmission are secure from any attacks and unauthorized access especially for sensitive and important digital data. This has been raised researcher’s concerns on security of the digital data. Digital data security has become one of the most important aspects in communication. Cryptography is one of the most important technology for protecting digital data. As there is need for secure communication, efficient and secure cryptographic processing is needed for desirable platform overall performance. Improvement of any communication platform with secure and complicated cryptographic algorithms incredibly relies on ideas of data safety that is essential within the current technological global. This paper propose a Secured Modified Advanced Encryption Standard Algorithm with decreasing the rounds of Advanced Encryption Standard (AES) to 14 rounds in order to minimize encryption and decryption process time and increasing digital data security as well. The results have been proved that the proposed technique provides higher efficiency in term of encryption and decryption process time compared to other researches while increase security which has been proved by using avalanche effect test.

Light detection experiment with avalanche photo diode and pin photo diode for green visible light communication

Visible Light Communication (VLC) has been attracting many researchers in the last decade to develop a lighting system as well as a communication system simultaneously. Light Emitting Diode (LED) for lighting systems are becoming more popular and widespread. It offers low consumption energy due to its energy transfer efficiency from electric to light. LED also offers a high response for modulation that makes it is also possible for communication purposes. Therefore, an improved configuration can provide a green communication system by reducing power consumption through combining lighting and communication system. Detection responsivity is a challenging issue to realize a VLC system. It will affect covered areas and obtained signal quality. This paper discusses the use of PIN photodiode and Avalanche Photo Diode (APD) for a detection device in a digital transmission data. This detector is generally used for fiber optic systems and offers an avalanche effect that can increase the obtained photocurrent. The obtained proper configuration and multiplication effect characteristics will be useful for designing a VLC system for green communication.

Designing Substitution Box Based on the 1D Logistic Map Chaotic System

Many researchers have tried to use the chaotic systems in generating different cryptographic tools, in order to provide high level of security to the data passing through network. In modern symmetric cryptographic systems, one of the most essential functions is a nonlinear mapping Substitution process which is responsible for creating the confusion between plaintext and ciphertext. It replaces each input bits by other bits using the lookup table S-Box. In this paper a new S-Box based on a 1D logistic map chaotic system was designed. The chaotic sequence generated from the 1D logistic map was processed to generate the hexa code values, and after that this hexa code also processed to construct the new good S-Box. This proposal was evaluated using the S-Box tests criteria including avalanche, balanced, completeness, strict avalanche, and invertibility. The analysis results show that the proposed S-Box passes all these statistical tests, has large avalanche effect and therefore the S-Box can avoid many attacks. The construction of both Substitution-Box and its inverse take only few milliseconds, so it can be used in many lightweight block ciphers.

E-ART: A New Encryption Algorithm Based on the Reflection of Binary Search Tree

Data security has become crucial to most enterprise and government applications due to the increasing amount of data generated, collected, and analyzed. Many algorithms have been developed to secure data storage and transmission. However, most existing solutions require multi-round functions to prevent differential and linear attacks. This results in longer execution times and greater memory consumption, which are not suitable for large datasets or delay-sensitive systems. To address these issues, this work proposes a novel algorithm that uses, on one hand, the reflection property of a balanced binary search tree data structure to minimize the overhead, and on the other hand, a dynamic offset to achieve a high security level. The performance and security of the proposed algorithm were compared to Advanced Encryption Standard and Data Encryption Standard symmetric encryption algorithms. The proposed algorithm achieved the lowest running time with comparable memory usage and satisfied the avalanche effect criterion with 50.1%. Furthermore, the randomness of the dynamic offset passed a series of National Institute of Standards and Technology (NIST) statistical tests.

A Low Area FPGA Implementation of Reversible Gate Encryption with Heterogeneous Key Generation

The reversible computation is the process of designing the architecture with reversible logic gates (RLG) and applicable for optical computing, digital signal processing, nanotechnologies and low-power circuits. In this study, integer wavelet transform (IWT) compression technique is applied to the input image to compress the pixel value. The utilization of the IWT is used to improve the quality of the image in terms of peak signal-to-noise ratio (PSNR) and structural similarity index matrix (SSIM). In addition, different types of RLGs are used to perform the encryption and decryption of the images. A random number is generated using the Lorenz chaotic system (LCS) that contains three different stages and each stage is developed using arithmetic blocks. Here, an effective key value is generated from the input image values by connecting the LCS’s output with the heterogeneous key generation (HKG) module. The inverse IWT (IIWT) technique is used to retrieve the original data during execution of decryption operation. Application specific integrated circuit and field-programmable gate array (FPGA) performances are calculated for reversible logic cryptographic design (RLCD) IWT-HKG architecture. The results showed that it has achieved better performance compared to conventional methods. Moreover, security analyses such as avalanche effect, side channel attack and session key agreement are performed for the RLCD-IWT-HKG method. The RLCD-IWT-HKG method has achieved 89 LUTs, 52 flip flops and 31 slices for the Virtex 6 FPGA device. After retrieving the decrypted images, values of PSNR and SSIM are evaluated as 39.90 dB and 0.6874, respectively.

Impacts of avalanche effects of price-optimized electric vehicle charging - Does demand response make it worse?

Electric vehicles (EVs) are expected to provide substantial potential for demand response (DR) and, thus, the integration of renewable electricity sources in the future energy system. However, DR can also have noticeable negative consequences, so-called avalanche effects. We systematically assess under which circumstances avalanche effects occur and what impact they have on the electricity system and cost savings for EV owners. Our results show that DR can provoke unwanted avalanche effects, which are particularly strong beyond 2030, when the leverage of EV charging will have increased to a significant level. It is possible to avoid avalanche effects by using a dynamically updated DR signal. If this is used, our findings confirm that shifting charging load from peaks to hours of low or negative residual load reduces the peak and variance of residual load and facilitates the integration of renewables.