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The secure hash algorithm 2 (SHA-2) family, including the SHA-224/256/384/512 hash functions, is widely adopted in many modern domains, ranging from Internet of Things devices to cryptocurrency. SHA-2 functions are often implemented on hardware to optimize performance and power. In addition to the high-performance and low-cost requirements, the hardware for SHA-2 must be highly flexible for many applications. This paper proposes an SHA-2 hardware architecture named the multimode SHA-2 accelerator (MSA), which has high performance and flexibility at the system-on-chip level. To achieve high performance and flexibility, our accelerator applies three optimal techniques. First, a multimode processing element architecture is proposed to enable the accelerator to compute various SHA-2 functions for many applications. Second, a three-stage arithmetic logic unit pipeline architecture is proposed to reduce the critical paths and hardware resources. Finally, nonce generator and nonce validator architectures are proposed to reduce memory access and maximize the performance of the proposed MSA for blockchain mining applications. The MSA accuracy is tested on a real hardware platform (the Xilinx Alveo U280 FPGA). The experimental results on the field programmable gate array (FPGA) prove that the proposed MSA achieves significantly better performance, hardware efficiency, and flexibility than previous works. The evaluation results for energy efficiency show that the proposed MSA achieves up to 38.05 Mhps/W, which is 543.6 and 29 times better than the state-of-the-art Intel i9-10940X CPU and RTX 3090 GPU, respectively.

The land is a very valuable asset for any government. It’s government job to ensure that the land registration and transfer are done without any fraud, good speed and transparency. The current land registration method employed by the governments are not open to frauds, hacks, and corruption of land records. Fraud is one of the major problems in land registration methods. In this study, the goal is to develop the framework by incorporating the blockchain technique that secures the land data during the land registration and transfer phases by preventing the fraud. The use of blockchain gives us the transparent, decentralized and robust infrastructure to build our framework upon. The blockchain technology is implemented with the asymmetric keys encryption/decryption that securely stores the land registration/transfer data. The data is held using encrypting with the public key of the landowner and storing a hash of the data. The use of the cryptographic function of hashing using SHA. The comparison of using SHA 256 and SHA 512 is given and discussed. The dataset used to compare results is created using 200 records of JSON objects with each object being identical for both SHA256 and SHA512 to remove data bias. The proposed framework with the SHA 512 performed 29% faster than the SHA 256. The results indicate our proposed framework performing better than the works proposed in current research land registration techniques.

Once there are constant or infrequently changed bits (COIBs) in two adjacent input messages of SHA-2, the switching power of input messages data registers (IMD-REGs) used for COIBs will disappear. Meanwhile, when full pipeline SHA-2 is applied in a certain application scenario where the IMD-REGs used for COIBs can be removed, more area of full pipeline SHA-2 can be saved as the proportion of IMD-REGs in message word registers increases. This paper proposes a new message expansion structure for full pipeline SHA-2 to increase the proportion of IMD-REGs. By inserting two expanders in last part of expansion structure pipeline stages and rescheduling the expander, the consumption rate of input messages will be decreased and the proportion of IMD-REGs will be increased. Compared with normal message expansion structure, the ratio of IMD-REGs to total message word registers in the proposed structure is increased from 15.1% to 41.6% for full pipeline SHA256, and 11.2% to 32.4% for full pipeline SHA512. When COIBs exists in adjacent input messages, the power and area advantages of proposed new message expansion structure have been demonstrated by FPGA and ASIC implementations.

Password-Based Key Derivation Function 2 (PBKDF2) is widely used cryptographic algorithm in order to generate secure keys to a password in various occasions. For example, it is used for file encryption and implementation of authentication systems, and so on. However, the generated derived key has a lower entropy than a general cryptography key, so its use is limited. To compensate for this the number of iteration counts of PBKDF2 should be increased. As the number of repetitive tasks increases, the entropy of the derived key increases, but it takes more time to generate the derived key. We present various optimization methods of PBKDF2. The main idea of our proposed method is reducing redundant block operations and optimizing the internal process of underlying Pseudo Random Function (PRF). In other words, we integrate several redundant operations and make full use of constant values used in PBKDF2. We use two HMAC algorithms: one using SHA-2 family and one using LSH family as the PRF of PBKDF2 (SHA-2 family is the most widely used hash functions, and LSH family is the latest hash function recently developed in South Korea). With our techniques, our implementations outperform Korea Internet & Security Agency (KISA) implementation by 121.26%, 325.91%, and 231.89% for using SHA256, LSH256, and LSH512 respectively; and also outperform OpenSSL implementation by 39.59% using SHA512. In addition, we show that the internal process of PBKDF2 can be computed independently. With our multi thread technique, our PBKDF2 implementations outperform KISA implementation by 2,152.66%, 1,986.85%, and 1,591.36% for using SHA256, LSH256, and LSH512 respectively; and our PBKDF2-HMAC-SHA512 implementation outperforms OpenSSL implementation by 523.57%. With our proposed implementation techniques, higher security can be achieved with more iteration operations. Furthermore, our optimization techniques can be easily expanded to optimize the performance of PBKDF2 on GPGPU and embedded devices.

In this article, an innovative encryption technique is developed by getting the inspiration from the natural up-down water wave’s phenomena that changes a reflection on pond’s surface. The plain image is considered as water pond and stones are throwing on the pond to diffuse the pixels. The direction of diffusion follows the pattern of natural water waves in 360 degrees. The distance traveled by the waves depend upon the weight of the stone i.e. heavier is the stone, longer will be the distance. Each layer of pixels in image represents Crest (Up) and Troughs (Down) around the hitting point of stone. The number of Crest and Troughs generated by a stone in radius are measured and are categorized into 1 to 6 or six levels (Layers). The concept of Crest and Trough in encryption are achieved by addition and subtraction of pseudo-random numbers in the pixel’s intensity. The pseudo random numbers are generated from Logistic map and transformed into stones of different weights ranges from 0-255. Before substitution, the pixels are shuffled in 1-dimensional vector using the index values of random numbers. The hash value is used for modification of initial seeds of the Logistic map. The initial seeds of the Logistic map are modified by the output of 256-bit hash function. Finally, the simulated results are compiled which ascertains that the projected algorithm achieves the required security standard with large pool of secret keys.

The cloud computing (CC) model is diverse as well as has broad phenomena because of which it is being preferred widely. Due to security challenges, the user cannot utilize CC to its full potentials. Storing their sensitive data in an insecure place is not even an option for these users. Many techniques were posited for securely amassing the data in the cloud; however, during massive transmission, none of them maintain end-to-end security. And, prevailing methods are also unable to solve the key intricacy and avoid key secrecy expose. Thus, for trouncing these disadvantages and also assuring the data transmission (DT) as of the source–destination, a secure DT scheme with the help of a distributed cloud server (CS) and data deduplication is proposed. The uploaded user data can well be amassed in disparate CS to ameliorate the user data’s security. It can be done by, first, extracting the features of the user data along with the CS. After that, the Hybrid Meerkat clan algorithm (HMCA) chose the CS, which is optimally centered on the features. Next, the SHA512 algorithm performs the data deduplication of the input user data. Subsequent to data deduplication, the input file is compressed and encrypted using a two-stage lempel–ziv algorithm and optimized CP-ABE-ECC algorithm. Lastly, the encrypted file is stored in the chosen CS. The experimentation is implemented to analyze the proposed method’s performance. The outcomes exhibited that the proposed work performed better contrasted to other prevailing algorithms.

The rise of the Internet of Things (IoT) and autonomous robots/vehicles comes with a lot of embedded electronic systems. Small printed circuit boards with microcomputers will be embedded almost everywhere. Therefore, the security and data protection of those systems will be a significant challenge to take into consideration for the future development of IoT devices. Cryptographic algorithms can be used to provide confidentiality and integrity for data transmitted between those embedded devices. It is important to know what kind of algorithm is the most suitable for the specified task and the selected embedded device. In this thesis, several commonly used cryptographic algorithms are evaluated and an EPS32 based IoT device is chosen as the evaluation platform. ESP32 is a series of low cost and low power System-on-Chip microcontrollers with integrated Wi-Fi and dual-mode Bluetooth. Additionally, ESP32 has the hardware acceleration feature for commonly used cryptographic algorithms. The goal of this thesis is to evaluate the performances of different cryptographic algorithms on the ESP32 with and without using the hardware acceleration feature. The execution times of different cryptographic algorithms processing data with varying sizes are collected, and the performance of each cryptographic algorithm is then evaluated. A data logging scenario is evaluated as a case study where the ESP32 periodically sends data to a remote database. Under different configurations of the ESP32, the transmission time of encrypted and non-encrypted communications via Hypertext Transfer Protocol Secure (HTTPS) and Hypertext Transfer Protocol (HTTP) will be compared. The results can be used to simplify the calculation of performance/protection trade-offs for specific algorithms. It also shows that the built-in hardware acceleration has a significant impact on increasing those algorithms’ performances. For Advanced Encryption Standard (AES), the throughput for encryption increased by 257.8%, and for decryption 222.7%. For Secure Hash Algorithm (SHA-2), the throughput increased by 165.2%. For Rivest-Shamir-Adleman (RSA), the encryption throughput has a decrease of 40.7%, and decryption has an increase of 184%. Furthermore, the results can also aid the design and development of a secure IoT system incorporating devices built with ESP32. Uppkomsten av Internet of Things (IoT) och autonoma robotar / fordon kommer med många inbyggda elektroniska system. Små kretskort med mikrodatorer kommer att vara inbäddade nästan överallt. Därför kommer säkerheten och dataskyddet för dessa system att vara en betydande utmaning att ta hänsyn till för den framtida utvecklingen av IoT-enheter. Kryptografiska algoritmer kan användas för att ge sekretess och integritet för data som överförs mellan de inbäddade enheterna. Det är viktigt att veta vilken typ av algoritm som är bäst lämpad för den angivna uppgiften och den valda inbäddade enheten. I denna avhandling utvärderas flera vanliga kryptografiska algoritmer och en EPS32-baserad IoT-enhet väljs som utvärderingsplattform. ESP32 är en serie av låga och lågeffektiva system-on-chip-mikrokontroller med integrerat Wi-Fi och dual-mode Bluetooth. Dessutom har ESP32 hårdvaruaccelereringsfunktionen för vanliga kryptografiska algoritmer. Målet med denna avhandling är att utvärdera prestanda för olika kryptografiska algoritmer på ESP32 med och utan att använda hårdvaruaccelereringsfunktionen. Exekveringstiderna för olika kryptografiska algoritmer som behandlar data med olika storlekar samlas in och prestanda för varje kryptografisk algoritm utvärderas sedan. Ett dataloggningsscenario utvärderas som en fallstudie där ESP32 regelbundet skickar data till en fjärrdatabas. Under olika konfigurationer av ESP32 jämförs överföringstiden för krypterad och icke-krypterad kommunikation via Hypertext Transfer Protocol Secure (HTTPS) och Hypertext Transfer Protocol (HTTP). Resultaten kan användas för att förenkla beräkningen av prestanda / skydda avvägningar för specifika algoritmer. Det visar också att den inbyggda hårdvaruaccelerationen har en betydande inverkan på att öka dessa algoritmers prestanda. För Advanced Encryption Standard (AES) ökade genomströmningen för kryptering med 257,8% och för dekryptering 222,7%. För Secure Hash Algorithm (SHA-2) ökade kapaciteten med 165,2%. För Rivest-Shamir-Adleman (RSA) har krypteringsflödet minskat med 40,7% och dekryptering har ökat med 184%. Dessutom kan resultaten också hjälpa till att utforma och utveckla ett säkert IoT-system som innehåller enheter byggda med ESP32.

The hashing is done by the block-chain technology during block creation. There are many hashing algorithms available, including SHA128, SHA256, SHA512, and MD5. It has been noticed that SHA256 is often utilized in block-chain. When selecting an effective hashing method, many variables such as storage space, time complexity, and collision ratio are taken into account. SHA256 is more resistant to collisions and takes up the least amount of space. The hashing method utilized in the proposed study is modified MD5. Traditional MD5, on the other hand, has a lower collision resistance than SHA256 but requires less storage space. The goal of this study is to offer a better modified MD5 method that is less time intensive and has greater collision resistance than conventional MD5. As a result, a system that is capable of providing security while also performing well is required. In this study, the modified MD5 was simulated for storage capacity and collision probability, as well as a CPU clock cycle simulation. When compared to MD5, SHA1, and SHA256, the modified MD5 results demonstrate improved collision resistance while using less storage space and time.

Preserving privacy and integrity is one of the important needs of any internet based platform especially if it is based on cloud. Block chain has been a recent technology key player in securing cloud based platforms. In the proposed work, we have used Blockchain technologies to provide encryption for cloud IoT results. Blockchain has recently become a promising software for cloud cluster integration and enhancement of cloud transaction protection and access to data and application codes. The main objective is to use blockchain technology to encrypt heterogeneous and enormous data. Authorizing the data obtained from different sources. Furthermore, more stable and better hash functions, such as SHA-256, SHA-384, and MD5 are now available, a future attacker would require more time to produce all available SHA512 hashes to brute force a hashed password from your database from a security standpoint. As a result, we consider SHA512 to be more robust and reliable in terms of the time it takes to compute a single hash when opposed to all other hash functions. As a result, we have introduced modified SHA512 in the proposed work for added reliability

Privacy and security of users data is an important concept involved in storing user information in a database. This paper discusses on how to securely store searchable string data in a database using standard encryption and hashing techniques. This method of storing string values in database prevent rainbow table attack .

Security information method for JPEG/exif documents generally aims to prevent security attacks by protecting documents with password and watermark. Both methods cannot be used to determine the condition of data integrity at the detection stage of the information security cycle. Message Digest is the essence of a file that has a function as a digital fingerprint to represent data integrity. This study aims to compile digital fingerprints to detect changes that occurred in JPEG / exif documents in information security. The research phase consists of five stages. The first stage, identification of the JPEG / exif document structure conducted using the Boyer-Moore string matching algorithm to find JPEG/exif segments location. The Second stage is segment content acquisition, conducted based on segment location and length obtained. The Third step, computing message digest for each segment using SHA512 hash function. Fourth stage, JPEG / exif document modification experiments to identified affected segments. The fifth stage is selecting and combining the hash value of the segment into the message digest. The obtained result shows the message digest for JPEG/exif documents composed of three hash values. The SOI segment hash value used to detect modifications for JPEG to png conversion and image editing. The APP1 hash value used to detect metadata editing. The SOF0 hash values use to detect modification for image recoloring, cropping and resizing — the combination from three hash values as JPEG/exif’s message digest.

A cryptographic hash work is a phenomenal class of hash work that has certain properties which make it fitting for use in cryptography. It is a numerical figuring that maps information of emotional size to a bit string of a settled size (a hash) and is expected to be a confined limit, that is, a limit which is infeasible to adjust. Hash Functions are significant instrument in information security over the web. The hash functions that are utilized in different security related applications are called cryptographic hash functions. This property is additionally valuable in numerous different applications, for example, production of digital signature and arbitrary number age and so on. The vast majority of the hash functions depend on Merkle-Damgard development, for example, MD-2, MD-4, MD-5, SHA-1, SHA-2, SHA-3 and so on, which are not hundred percent safe from assaults. The paper talks about a portion of the secure hash function, that are conceivable on this development, and accordingly on these hash functions additionally face same attacks.

An innovative and highly efficient color image encryption technique based on the concept of linear transformation is presented in this paper. A 24-bit color image is split into the channels called Red, Green, Blue and afterwards each channel is permuted via cyclic shift on rows and columns using chaotic sequences. For substitution, pseudo-random numbers are generated using chaotic maps, which are then build into pseudo-random matrices through Linear Transformations. These random matrices are bonded with permuted colored channel under Exclusive-OR (XOR) operation. The control parameters and initial conditions for chaotic maps are obtained from 256-bits hash value of the original image to avoid the chosen-plaintext attacks. The comparison of simulated results with existing algorithms has shown the proposed algorithm is better in encryption robustness and better in noise repulsion during transmission. The proposed technique is most suitable for real time applications due to better efficiency.

A Secure hash algorithm is grounded on the principles of message digest algorithms that are used in the design of the algorithms like MD4 and MD5. The main application of this algorithm is that it can be used in security applications for authentication and data validation like message authentication, digital signature and fingerprinting. It can also be used in detecting duplicate data and uniquely identifying files. In this paper we analyzed the role of some of the building blocks of SHA-2 family .We have demonstrated that the disturbance correction strategy is applicable to the SHA-512 architecture and proved that functions Σ, ∂ are vital for the security of SHA-512, without them it is possible to find collisions with complexity 264 hash operations. We also demonstrated the functioning of 256- bit which was previously designed for 32 bit architecture but in this paper it is implemented using 64- bit architecture.

Hash functions are a crucial tool in a large variety of applications, ranging from security protocols to cryptocurrencies down to the Internet-of-Things devices used, for example, as biomedical appliances. In particular, SHA-2 is today a ubiquitous hashing primitive. Its acceleration has driven a wealth of contributions in the technical literature and even a whole industry segment involving dedicated hash processing accelerators. Because of the variety of requirements in terms of performance, resources, and energy consumption as well as the impact of the particular hardware technology of choice, evaluating and comparing different architectural schemes is a nontrivial task, along with the exploration of new solutions matching given user requirements. Based on a careful review of the state of the art, this paper introduces an SHA-2 workbench to be used as a framework for evaluating different implementation styles and architectural choices. The workbench comes in the form of a generic HDL description, where the various implementation options are exposed in the form of user-configurable parameters and can be variously combined obtaining either known solutions or possibly new configurations to be explored. We systematically use the workbench to analyze the available SHA-2 architectural techniques. This extensive evaluation provides a deep understanding of the performance and energy implications of each implementation style and even allows the identification of nonobvious matches between architectural choices and target technologies in order to optimize hash rate and area efficiency figures.