A Survey of Oblivious Transfer Protocol

Oblivious transfer (OT) protocol is an essential tool in cryptography that provides a wide range of applications like secure multi-party computation, private information retrieval, private set intersection, contract signing, and privacy-preserving location-based services. The OT protocol has different variants such as one-out-of-2, one-out-of- n , k -out-of- n , and OT extension. In the OT (one-out-of-2, one-out-of- n , and OT extension) protocol, the sender has a set of messages, whereas the receiver has a key. The receiver sends that key to the sender in a secure way; the sender cannot get any information about the received key. The sender encrypts every message by operating on every message using the received key and sends all the encrypted messages to the receiver. The receiver is able to extract only the required message using his key. However, in the k -out-of- n OT protocol, the receiver sends a set of k keys to the sender, and in replay, the sender sends all the encrypted messages. The receiver uses his keys and extracts the required messages, but it cannot gain any information about the messages that it has not requested. Generally, the OT protocol requires high communication and computation cost if we transfer millions of oblivious messages. The OT extension protocol provides a solution for this, where the receiver transfers a set of keys to the sender by executing a few numbers of OT protocols. Then, the sender encrypts all the messages using cheap symmetric key cryptography with the help of a received set of keys and transfer millions of oblivious messages to the receiver. In this work, we present different variants of OT protocols such as one-out-of-2, one-out-of- n , k -out-of- n , and OT extension. Furthermore, we cover various aspects of theoretical security guarantees such as semi-honest and malicious adversaries, universally composable, used techniques, computation, and communication efficiency aspects. From the analysis, we found that the semi-honest adversary-based OT protocols required low communication and computation costs as compared to malicious adversary-based OT protocols.

A Comprehensive Review of Cryptographic Algorithms

The internet has revolutionized advancements, it’s conveniences and uses come at the price of new perils. To be safe from being the victim of fraud, theft and other damage security and vigilance is critical. Cryptography plays an important role in securing information and communications using a set of rules, it ensures the integrity of our data. It maintains confidentiality by protecting the privacy of personal information stored in enterprise systems. Hence Encryption is the only way to ensure that your information remains secure while it is stored and being transmitted. Cryptographic Algorithms mathematically maintain the integrity, confidentiality and authenticity of sensitive information by preventing data disclosure, data tampering and repudiation. The three main types of cryptography are Symmetric Key Cryptography, Asymmetric Key Cryptography and Hash Functions. In this Paper, several important algorithms used for encryption and decryption are defined and analysed, the algorithms are DES, AES, ECC, RSA, MD5 Keywords: Cryptography, Encryption, Decryption, AES, DES, ECC, RSA, Blowfish, MD5

Analysis and software implementation of the modified cryptographic Vernam cipher and the Caesar cipher

Problem. Modern cryptography is a very important part of cybersecurity and confidentiality of many operations. It covers almost all parts of our lives, from e-commerce to specialized education of students. Goal. The advantage of symmetric key cryptography is that working with this method is very easy for users, as one key is used for encryption, as well as for decryption purposes, and this key must be secret and should be known only to the sender and recipient and no one else. On the other hand, public key cryptography has two keys. Unfortunately, this exposes the inherent security flaws, as the integrity of the encryption depends entirely on the password. It was decided to consider the implementation of a modified symmetric Vernam cipher that avoids these problems, and its modification and experimental studies should further strengthen data protection. Methodology. Higher mathematics, linear algebra are very important subjects. But if we want to encourage students with cryptography, we need to use all aspects of the IT cluster more effectively. Ideal for this is the implementation of algorithms and programs using programming languages. It is very important and useful for students studying Cybersecurity to illustrate where and how it is possible to create software implementations of encryption / decryption methods. Results. The article presents the analysis and implementation of the modified cryptographic Vernam cipher and Caesar cipher using a concept that combines modern programming languages and the principles of cryptography, which students study in subject-oriented specialties. Originality. An original approach to teaching Cybersecurity students by implementing ciphers using applied programming is described. Practical value. Using cryptography as a learning tool will help students develop their programming skills and effectively understand the concept of cybersecurity in real-world examples.

An Implementation of Picpass Algorithm for the Solution of Key Exchange Problem

In this dissertation a PicPass algorithm is proposed for the solution of Key Exchange problem using Symmetric and Asymmetric key cryptography. Diffie and Hellman proposed an algorithm for key exchange. But this algorithm suffers from Man-in middle attack. So to overcome this problem Seo proposed another algorithm that uses text password for the agreement between two parties. But again the password suffers from offline dictionary attack. In this, a PicPass Protocol i.e. picture is used as a password to make an agreement between two parties. The protocol contains two function i.e. picture function as well as distortion function is used to make picture in a compact size and then it is sent to receiver. Firstly the sender encrypts the Plain Text using Secret Picture and creates the Cipher Text using Symmetric key cryptography. Then the Secret Picture will be encrypted by covered picture resulting into Encrypted Picture. Now the Cipher Text and Encrypted Picture will be placed into digital envelope and then the envelope will be send to the receiver. The receiver will receive the digital envelope, open it and then decrypt the Encrypted Picture using his Key Picture. This will result the receiver to get the Secret Picture. Now the receiver will open the Cipher Text using the Secret Picture and get the Plain Text. In between if any person wants to predict the Encrypted Picture then he cannot guess as the picture will only be decrypted using the Secret Key which will be only with the receiver. So in this dissertation, a picture is used as a password to authenticate key exchange is that gives practical solution against offline dictionary attacks only by using both private and public key cryptography.

Privacy-Preserving Authentication Scheme for Roaming Service in Global Mobility Networks

With the rapid development of mobile intelligent technologies and services, users can freely experience ubiquitous services in global mobility networks. It is necessary to provide authentications and protection to the privacy of mobile users. Until now, many authentication and privacy schemes were proposed. However, most of the schemes have been exposed to some security problems. Recently, Madhusudhan and Shashidhara (M&S) proposed a lightweight authentication scheme, denoted as the M&S scheme, for roaming services in global mobility networks. This paper shows that the M&S scheme has security flaws including two masquerading attacks and a mobile user trace attack. After that, we propose a privacypreserving authentication scheme for global mobility networks. The proposed scheme not only focused on the required security but also added privacy concerns focused on anonymity based on a dynamic pseudonym, which is based on exclusive-or operation, hash operation and symmetric key cryptography. Formal security analysis is performed based on Burrow-Abadi-Needdham (BAN) logic and the ProVerif tool, which concludes that the proposed scheme is secure. The analysis shows that the proposed authentication scheme is secure and provides privacy with a reasonable performance.

Implementation & Comparative Analysis of RSA, Caesar Cipher and Playfair Cipher

With the growing use of the Internet, and more people being connected with it, the security of the data becomes a major concern. It is necessary that the data can only be accessed by the intended receiver and no person in the middle makes alterations to it. This is achieved by encryption of the data using cryptography. This paper presents a comparative analysis of RSA (Rivest-Shamir-Adleman), Caesar Cipher and Playfair Cipher cryptographic techniques. This paper also presents a comparative analysis of Symmetric Key Cryptography and Asymmetric Key Cryptography. Also, this paper includes the basic working of the above-mentioned techniques along with their implementation in C language over Visual Studio Code 1.49.3.

A Novel Asymmetric Hyperchaotic Image Encryption Scheme Based on Elliptic Curve Cryptography

Most of the image encryption schemes based on chaos have so far employed symmetric key cryptography, which leads to a situation where the key cannot be transmitted in public channels, thus limiting their extended application. Based on the elliptic curve cryptography (ECC), we proposed a public key image encryption method where the hash value derived from the plain image was encrypted by ECC. Furthermore, during image permutation, a novel algorithm based on different-sized block was proposed. The plain image was firstly divided into five planes according to the amount of information contained in different bits: the combination of the low 4 bits, and other four planes of high 4 bits respectively. Second, for different planes, the corresponding method of block partition was followed by the rule that the higher the bit plane, the smaller the size of the partitioned block as a basic unit for permutation. In the diffusion phase, the used hyperchaotic sequences in permutation were applied to improve the efficiency. Lots of experimental simulations and cryptanalyses were implemented in which the NPCR and UACI are 99.6124% and 33.4600% respectively, which all suggested that it can effectively resist statistical analysis attacks and chosen plaintext attacks.

Efficient Implementation of PRESENT and GIFT on Quantum Computers

Grover search algorithm is the most representative quantum attack method that threatens the security of symmetric key cryptography. If the Grover search algorithm is applied to symmetric key cryptography, the security level of target symmetric key cryptography can be lowered from n-bit to n2-bit. When applying Grover’s search algorithm to the block cipher that is the target of potential quantum attacks, the target block cipher must be implemented as quantum circuits. Starting with the AES block cipher, a number of works have been conducted to optimize and implement target block ciphers into quantum circuits. Recently, many studies have been published to implement lightweight block ciphers as quantum circuits. In this paper, we present optimal quantum circuit designs of symmetric key cryptography, including PRESENT and GIFT block ciphers. The proposed method optimized PRESENT and GIFT block ciphers by minimizing qubits, quantum gates, and circuit depth. We compare proposed PRESENT and GIFT quantum circuits with other results of lightweight block cipher implementations in quantum circuits. Finally, quantum resources of PRESENT and GIFT block ciphers required for the oracle of the Grover search algorithm were estimated.