It has been predicted that more devices will be connected to the internet network along with the development of IoT, and that will increase the complexity in the security system. The most important thing in security systems is the process of encryption and authentication. Various encryption techniques are developed to overcome security problems of the data. One of the methods used for authentication of data is Zero Knowledge Proof. This method works to identify the authenticity of someones statement to proof without showing any knowledge of the statement mentioned. This research will mainly discuss about the security of data transmission system by combining data encryption and data authentication. The proposed data encryption is using Advanced Encryption System and method for authentication of data using the Zero Knowledge Proof. This research will conduct the development methods of authentication Zero Knowledge Proof from previous research and the result was compared with the proposed method based on the simulation results transmission system client and server. Experiments will be conducted using thirty-text data, each of data will be measured on the performance of both encryption and authentication process between the previous method and proposed method. Experimental results show the performance of the proposed method has better speed to process application for security of data transmission systems, with performance to authenticate approximately 5 ms from the client side and server side.
MOSES DOGONYARO NOEL, Onomza Victor Waziri, Shafi’i Muhammad Abdulhamid, Adebayo Joseph Ojeniyi · 5 authors
The use of public key cryptosystems ranges from securely encrypting bitcoin transactions and creating digital signatures for non-repudiation. The cryptographic systems security of public key depends on the complexity in solving mathematical problems. Quantum computers pose a threat to the current day algorithms used. This research presents analysis of two Hash-based Signature Schemes (MSS and W-OTS) and provides a comparative analysis of them. The comparisons are based on their efficiency as regards to their key generation, signature generation and verification time. These algorithms are compared with two classical algorithms (RSA and ECDSA) used in bitcoin transaction security. The results as shown in table II indicates that RSA key generation takes 0.2012s, signature generation takes 0.0778s and signature verification is 0.0040s. ECDSA key generation is 0.1378s, signature generation takes 0.0187s, and verification time for the signature is 0.0164s. The W-OTS key generation is 0.002s. To generate a signature in W-OTS, it takes 0.001s and verification time for the signature is 0.0002s. Lastly MSS Key generation, signature generation and verification has high values which are 16.290s, 17.474s, and 13.494s respectively. Based on the results, W-OTS is recommended for bitcoin transaction security because of its efficiency and ability to resist quantum computer attacks on the bitcoin network.
Ethan Heilman, Neha Narula, Garrett Tanzer, James Peter Thomas. Lovejoy · 7 authors
We present attacks on the cryptography formerly used in the IOTA blockchain, including under certain conditions the ability to forge signatures. We developed practical attacks on IOTA’s cryptographic hash function Curl-P-27, allowing us to quickly generate short colliding messages. These collisions work even for messages of the same length. Exploiting these weaknesses in Curl-P-27, we broke the EUCMA security of the former IOTA Signature Scheme (ISS). Finally, we show that in a chosen-message setting we could forge signatures and multi-signatures of valid spending transactions (called bundles in IOTA).
Ripple Effect is a logic puzzle where the player has to fill numbers into empty cells in a rectangular grid. The grid is divided into rooms, and each room must contain consecutive integers starting from 1 to its size. Also, if two cells in the same row or column contain the same number $x$, there must be a space of at least $x$ cells separating the two cells. In this paper, we develop a physical zero-knowledge proof for the Ripple Effect puzzle using a deck of cards, which allows a prover to convince a verifier that he/she knows a solution without revealing it. In particular, given a secret number $x$ and a list of numbers, our protocol can physically verify that $x$ does not appear among the first $x$ numbers in the list without revealing $x$ or any number in the list.
Open access
3 source records
Cryptography and Data Security
Chaos-based Image/Signal Encryption
Advanced Steganography and Watermarking Techniques
Abstract Bitcoin’s security relies solely on cryptographic primitives, namely on digital signatures, hash functions and Merkle trees. This chapter discusses the security of the Bitcoin system if some primitives become weaker due to advances in cryptanalysis, an increasing computing power of the adversaries or improper software implementations. The chapter starts with a general overview of the primitives in use, explaining possible attack strategies against each of them, which is followed by combined attack strategies. The chapter closes by showing the consequences of Grover’s and Shor’s quantum algorithms for Bitcoin’s security.
<span>Text password has long been a dominant approach to user authentication used by a huge quantity of Internet services. Web applications are now widely used for the implementation of a range of significant services. The securing of such applications has thus become a significant process. Currently the frequent use of passwords and the need for them make them more vulnerable to theft or guesswork. In the proposed research, the researcher designed an algorithm that has the ability to perform registration or to access web applications safely. The researcher designed an algorithm in the proposed research, which has the ability to securely perform registration or access web applications. The proposed idea based on the notion of Zero-knowledge proof. A complex generation of random number initiated by proposed novel 6D-Hyper chaotic system. The bottom line is that both parties (web application, user), have a secret number. These two numbers used to do the process of registration without requiring a password. Results from the research showed the importance of the proposed method by which the keys were managed and distributed in a safe and effective way.</span>
The patients' medical image data are one of the most important data in e-health. Medical image data usually play a crucial role in disease diagnosis and implicate unpredictable potential values for improving diagnostic methods and adjusting diagnostic results. To exploit their incredible potential values, medical images need to be shared among different hospitals, medical institutions and insurance companies and others. But how to securely and effectively share these medical image data becomes a challenging problem. In this paper, we proposed to combine encryption and digital watermark technology to achieve a secure and privacy-preserving medical image sharing method. The QR code image of the concatenation of authoritative diagnosis results and the hash of the original medical image is generated as the watermark image. The Discrete cosine transform (DCT) and Inverse DCT (IDCT) algorithms are utilized to embed the watermark image. As the watermarked medical images are desensitized, they are stored to a smart contract based blockchain, such as Ethereum, to achieve secure and fair sharing between data owners and users. The experimental results show that the proposed method can resist several attacks meanwhile it is efficient in medical image sharing.
Open access
Advanced Steganography and Watermarking Techniques
Віктор Миколайович Чешун, Ihor Muliar, Vasyl Yatskiv, Ruslan Shevchuk · 6 authors
Decentralized applications, architectures and Blockchain are very popular and progressive technologies that are definitely ahead of its time. Nowadays world has a lot of decentralized applications and proposals, however the approaches and concepts decentralized software development based on the Blockchain technology is only emerging. This process is a common thing for new technologies as far as its adaptation takes time and often requires to change a usual approach to it. This article suggests a new way of safe decentralized applications development using Blockchain technologies and Ethereum platform. Ethereum platform-it's a project that is undoubtedly second best after bitcoin for a quite long period of time. Ethereum is presented as a platform for various tasks, such as maintaining a stable application performance in case of any threats. The main object of the research are the decentralized applications, build on a Ethereum platform basis using the smart-contracts algorithm. The study helped to improve an existing crypto-token allocating model which goal is acquiring more stable performance. On the basis of improved model a new method of allocating cryptotokens in decentralized Ethereum applications was developed, defined a main stage of apps elaboration, offered an allocating crypto-token algorithm which is able to use associative tables and dictionaries.
Blockchain Technology Applications and Security
Advanced Steganography and Watermarking Techniques
Sumaia Atiwa, Yunus Dawji, Ahmed Refaey, Sebastian Magierowski
Interest in the efficient implementations of hashing algorithms has received even more attention recently due to the growing application-space for blockchain technology. Consequently, a pressing need has arisen to develop high-performance hashing techniques to support these developments. In this paper, an architecture and VLSI implementation of the newest hashing standard, BLAKE2, is presented. The Equihash algorithm serves as a use case for BLAKE2 in Blockchain. An FPGA-based custom computing machine (FCCM) approach is used. This approach is producing an accelerated Equihash hashing-core system which is 5x faster than an ARM Cortex-A9 based system on a ZC706 SoC chip for 0.27 W. Indeed, this is the first BLAKE2 implementation allowing fast execution, and effective substitution of any previous hash families implementations.
Chaos-based Image/Signal Encryption
Cryptographic Implementations and Security
Advanced Steganography and Watermarking Techniques
Picnic is a post-quantum digital signature scheme, where the security is based on the difficulty of inverting a symmetric block cipher and zero-knowledge proofs. However, generating a Picnic signature to a specific message requires up to 300 kB content depending RAM. As the memory of an IoT device is limited this can lead to issues at the implementation. Our target is bringing post-quantum cryptography to IoT systems. We propose three structural adjustments of the Picnic algorithm to reduce the memory usage. Two adjustments are compatible with the reference implementation, one of them breaks backward compatibility. We show analytically that the content depending memory for generating a signature can be decreased to under 10 kB.With these adjustments, Picnic becomes suitable for IoT devices with little RAM. Since our approach also aims at easier parallelization, a speed-up depending on the number of instances is possible.
The bioinformatics features are collected by pattern recognition technology, and the digital coding and format conversion of the feature data are realized by using the theory of topological group transformation. Authentication and Signature based on Zero Knowledge Proof Technology can be used as the trusted credentials of cloud platform and cannot be forged, thus realizing trusted and secure access.
Ward Beullens, Tim Beyne, Aleksei Udovenko, Giuseppe Vitto
The Legendre PRF relies on the conjectured pseudorandomness properties of the Legendre symbol with a hidden shift. Originally proposed as a PRG by Damgård at CRYPTO 1988, it was recently suggested as an efficient PRF for multiparty computation purposes by Grassi et al. at CCS 2016. Moreover, the Legendre PRF is being considered for usage in the Ethereum 2.0 blockchain. This paper improves previous attacks on the Legendre PRF and its higher-degree variant due to Khovratovich by reducing the time complexity from O(< (p log p/M) to O(p log2 p/M2) Legendre symbol evaluations when M ≤ 4√ p log2 p queries are available. The practical relevance of our improved attack is demonstrated by breaking three concrete instances of the PRF proposed by the Ethereum foundation. Furthermore, we generalize our attack in a nontrivial way to the higher-degree variant of the Legendre PRF and we point out a large class of weak keys for this construction. Lastly, we provide the first security analysis of two additional generalizations of the Legendre PRF originally proposed by Damgård in the PRG setting, namely the Jacobi PRF and the power residue PRF.
The cryptographic algorithm has been gradually improved in design, but its implementations are vulnerable to side‐channel analysis (SCA). Generally speaking, adding a mask to the primitive is the best way to counteract SCA. In the high‐order mask, the key to affecting performance and security lies in the multiplication design. Based on the research of the advanced encryption standard (AES) algorithm, internal round function structure, and zero‐knowledge proof, a high‐order AES mask scheme is designed to optimise the implementation. In this scheme, the substitution‐box protects sensitive variables in the algorithm with the use of secure multiplication and secure inversion by column. The scheme named as in columns higher‐order mask (ICHM), features low cost and high security. The result of the experiment proves the security and effectiveness of the ICHM.
Cryptographic Implementations and Security
Chaos-based Image/Signal Encryption
Physical Unclonable Functions (PUFs) and Hardware Security
Recently, cryptocurrencies such as Bitcoin, Ethereum, etc, have rapidly been recognized as an asset, often called a digital asset. Comparing to the real assets, it would be handled carefully due to its own characteristics that are completely different. The disadvantage of such digital assets, on the one hand, is that whoever knows the private key of the wallet, they can easily take over that digital asset. On the other hand, if the wallet’s owners are dead without passing credential information to others, that asset will be lost forever. We thus propose the novel secure testament methodology for a digital asset such as Bitcoin to solve the mentioned problems. The mechanism is based on managing the mnemonic seed of the wallet so that an inheritor will obtain the mnemonic seed in a secure way. Two mechanisms of the proposed methodology are implemented. The first is to save the mnemonic seed in a secure repository. Therefore, no one can access to the cryptocurrency wallet while the owner still being alive and does not wish anybody to access. The second is to deliver the mnemonic seed securely to legitimate inheritor when the owner is suspected to be dead or disappeared. Finally, based on our experiment, the results show that the aforementioned problems can be solved. Furthermore, the proposed mechanism can help the owner of the asset to managing the confidentiality of their assets.
Advanced Steganography and Watermarking Techniques
Smart cameras and image sensors are widely used in industrial processes, from the designing to the quality checking of the final product. Images generated by these sensors are at continuous risk of disclosure and privacy breach in the industrial Internet of Things (IIoT). Traditional solutions to secure sensitive data fade in IIoT environments because of the involvement of third parties. Blockchain technology is the modern-day solution for trust issues and eliminating or minimizing the role of the third party. In the context of the IIoT, we propose a permissioned private blockchain-based solution to secure the image while encrypting it. In this scheme, the cryptographic pixel values of an image are stored on the blockchain, ensuring the privacy and security of the image data. Based on the number of pixels change rate (NPCR), the unified averaged changed intensity (UACI), and information entropy analysis, we evaluate the strength of proposed image encryption algorithm ciphers with respect to differential attacks. We obtained entropy values near to an ideal value of 8, which is considered to be safe from brute force attack. Encrypted results show that the proposed scheme is highly effective for data leakage prevention and security.
Open access
Chaos-based Image/Signal Encryption
Blockchain Technology Applications and Security
Advanced Steganography and Watermarking Techniques
Santosh Pandurang Jadhav, Georgi Balabanov, Vladimir Poulkov, Javed Shaikh
IoT is spreading rapidly from industry to domestic application such as home automation and gathering sensitive data through IoT devices hence the security of these devices and the data transmission is of great importance. Because of the resource constraint devices, lightweight cryptographic protocol plays an important role. Therefore, implementing the zero-knowledge proof along with the hyper elliptic curve cryptography enhances the security and efficiency in the resource constraint devices.
Cryptography and Data Security
Advanced Steganography and Watermarking Techniques
In this article, we propose a key secret-sharing technology based on generative adversarial networks (GANs) to address three major problems in the blockchain: 1) low security; 2) hard recovery of lost keys; and 3) low communication efficiency. In our scheme, the proposed network plays the role of a dealer and treats the secret-sharing process as a classification issue. The key idea is to view the secret as an image during the secret-sharing process. If the user's private key is text, we can covert the key text into an image called the original image. Specifically, we first divide the original image into original subimages by the image segmentation. Next, we encode each original subimage by DNA coding. Finally, we train the proposed network to find the key secret-sharing results. Our proposed scheme is not only a significant extension of the GANs but also a new direction for the key secret-sharing technology. The simulation results show that the scheme is secure, and both flexible and efficient in communication.
Advanced Steganography and Watermarking Techniques
Abstract Port Knocking is a method for authenticating clients through a closed stance firewall, and authorising their requested actions, enabling severs to offer services to authenticated clients, without opening ports on the firewall. Advances in port knocking have resulted in an increase in complexity in design, preventing port knocking solutions from realising their potential. This paper proposes a novel port knocking solution, named Crucible, which is a secure method of authentication, with high usability and features of stealth, allowing servers and services to remain hidden and protected. Crucible is a stateless solution, only requiring the client memorise a command, the server’s IP and a chosen password. The solution is forwarded as a method for protecting servers against attacks ranging from port scans, to zero-day exploitation. To act as a random oracle for both client and server, cryptographic hashes were generated through chaotic systems.
Víctor Gayoso Martínez, Luis Hernández–Álvarez, Luis Hernández Encinas
Blockchain is one of the most interesting emerging technologies nowadays, with applications ranging from cryptocurrencies to smart contracts. This paper presents a review of the cryptographic tools necessary to understand the fundamentals of this technology and the foundations of its security. Among other elements, hash functions, digital signatures, elliptic curves, and Merkle trees are reviewed in the scope of their usage as building blocks of this technology.
The field of post-quantum cryptography studies cryptographic systems that are secure against an adversary in possession of a quantum computer. In 2017, the National Institute of Standards and Technology (NIST) initiated a process to standardize quantum-resistant public-key cryptographic algorithms (NIST PQC Project). In this thesis we analyze the performance and security of the Bit-Flipping Key Encapsulation Mechanism (BIKE) -- one of the candidates in the NIST PQC project which advanced to the second round of the standardization process. BIKE is a code-based cryptographic system featuring three different variants of the protocol. In the first round of the NIST PQC project BIKE offered security only against chosen-plaintext attacks (CPA). In the second round, BIKE introduced three new variants that are claimed to be secure also against chosen-ciphertext attacks (CCA). Firstly, we build a secure implementation of the CCA protocol and show that its performance characteristics are only negligibly worse than the CPA variant. In the key decapsulation phase of the protocol BIKE uses a decoding algorithm which fails with some probability, called the Decoding Failure Rate (DFR). We analyze the DFR of two decoders used in BIKE, Back-Flip and Black-Gray, and propose a new decoder, called Black-Gray-Flip, that achieves the same DFR as the two previously used decoders while being almost twice as fast. Finally, we propose an algorithm for inversion of binary polynomials in a polynomial ring used in BIKE-2, the second variant of BIKE. Our implementation of the inversion significantly outperforms previously used algorithms. With this and the fact that the bandwidth requirement for BIKE-2 is the smallest among the three variants, BIKE-2 is positioned as the preferable variant of BIKE. The second part of this thesis studies the Legendre pseudorandom function (PRF) which is proposed to be used in the context of blockchains. We present a new algorithm for cryptanalysis of the Legendre PRF. The complexity of our algorithm is lower than the previous best known algorithm. Moreover, we show the results of breaking three Legendre PRF challenges posed by the Ethereum foundation. The most difficult challenge that we solved set the new record which is not broken so far.
Modern machine learning techniques have achieved surprisingly good standard test accuracy, yet classical machine learning theory has been unable to explain the underlying reason behind this success. The phenomenon of adversarial examples further complicates our understanding of what it means to have good generalization ability. Classifiers that generalize well to the test set are easily fooled by imperceptible image modifications, which can often be computed without knowledge of the classifier itself. The adversarial error of a classifier measures the error under which each test data point can be modified by an algorithm before it is given as input to the classifier. Followup work has showed that a tradeoff exists between optimizing for standard generalization error versus for adversarial error. This calls into question whether standard generalization error is the correct metric to measure. We try to understand the generalization capability of modern machine learning techniques through the lens of adversarial examples. To reconcile the apparent tradeoff between the two competing notions of error, we create new security definitions and classifier constructions which allow us to prove an upper bound on the adversarial error that decreases as standard test error decreases. We introduce a cryptographic proof technique by defining a security assumption in a simpler attack setting and proving a security reduction from a restricted black-box attack problem to this security assumption. We then investigate the double descent curve in the interpolation regime, where test error can continue to decrease even after training error has reached zero, to give a natural explanation for the observed tradeoff between adversarial error and standard generalization error. The second part of our work investigates further this notion of a black-box model by looking at the separation between being able to evaluate a function and being able to actually understand it. This is formalized through the notion of function obfuscation in cryptography. Given some concrete implementation of a function, the implementation is considered obfuscated if a user cannot produce the function output on a test input without querying the implementation itself. This means that a user cannot actually learn or understand the function even though all of the implementation details are presented in the clear. As expected this is a very strong requirement that does not exist for all functions one might be interested in. In our work we make progress on providing obfuscation schemes for simple, explicit function classes. The last part of our work investigates non-statistical biases and algorithms for nonconvex optimization problems. We show that the continuous-time limit of stochastic gradient descent does not converge directly to the local optimum, but rather has a bias term which grows with the step size. We also construct novel, non-statistical algorithms for two parametric learning problems by employing lattice basis reduction techniques from cryptography.