Cryptography, Volume 2, Issue 1 (March 2018) – 6 articles

Modern computer microarchitectures build on well-established foundations that have encouraged a pattern of computational homogeneity that many cyberattacks depend on. We suggest that balanced ternary logic can be valuable to Internet of Things (IoT) security, authentication of connected vehicles, as well as hardware and software assurance, and have developed a ternary encryption scheme between a computer and smartcard based on public key exchange through non-secure communication channels to demonstrate the value of balanced ternary systems. The concurrent generation of private keys by the computer and the smartcard uses ternary schemes and cryptographic primitives such as ternary physical unclonable functions. While general purpose ternary computers have not succeeded in general use, heterogeneous computing systems with small ternary computing units dedicated to cryptographic functions have the potential to improve information assurance, and may also be designed to execute binary legacy codes. Full article

The threat of quantum-computer-assisted cryptanalysis is forcing the security community to develop new types of security protocols. These solutions must be secure against classical and post-quantum cryptanalysis techniques as well as feasible for all kinds of devices, including energy-restricted Internet of Things (IoT) devices. The quantum immunity can be implemented in the cryptographic layer, e.g., by using recent lattice-based key exchange algorithms NewHope or Frodo, or in the physical layer of wireless communication, by utilizing eavesdropping-resistant secrecy coding techniques. In this study, we explore and compare the feasibility and energy efficiency of selected cryptographic layer and physical layer approaches by applying an evaluation approach that is based on simulation and modeling. In particular, we consider NewHope and Frodo key exchange algorithms as well as novel physical layer secrecy coding approach that is based on polar codes. The results reveal that our proposed physical layer implementation is very competitive with respect to the cryptographic solutions, particularly in short-range wireless communication. We also observed that the total energy consumption is unequally divided between transmitting and receiving devices in all the studied approaches. This may be an advantage when designing security architectures for energy-restricted devices. Full article

This paper investigates the application of fault attacks to the authenticated encryption stream cipher algorithm MORUS. We propose fault attacks on MORUS with two different goals: one to breach the confidentiality component, and the other to breach the integrity component. For the fault attack on the confidentiality component of MORUS, we propose two different types of key recovery. The first type is a partial key recovery using a permanent fault model, except for one of the variants of MORUS where the full key is recovered with this model. The second type is a full key recovery using a transient fault model, at the cost of a higher number of faults compared to the permanent fault model. Finally, we describe a fault attack on the integrity component of MORUS, which performs a forgery using the bit-flipping fault model. Full article

Security issues of typical Voice over Internet Protocol (VoIP) applications are studied in this paper; in particular, the open source Linphone application is being used as a case study. An experimental analysis indicates that protecting signalling data with the TLS protocol, which unfortunately is not always the default option, is needed to alleviate several security concerns. Moreover, towards improving security, it is shown that a VoIP application may operate over a virtual private network without significantly degrading the overall performance. The conclusions of this study provide useful insights to the usage of any VoIP application. Full article

Today, digitalization decisively penetrates all the sides of the modern society. One of the key enablers to maintain this process secure is authentication. It covers many different areas of a hyper-connected world, including online payments, communications, access right management, etc. This work sheds light on the evolution of authentication systems towards Multi-Factor Authentication (MFA) starting from Single-Factor Authentication (SFA) and through Two-Factor Authentication (2FA). Particularly, MFA is expected to be utilized for human-to-everything interactions by enabling fast, user-friendly, and reliable authentication when accessing a service. This paper surveys the already available and emerging sensors (factor providers) that allow for authenticating a user with the system directly or by involving the cloud. The corresponding challenges from the user as well as the service provider perspective are also reviewed. The MFA system based on reversed Lagrange polynomial within Shamir’s Secret Sharing (SSS) scheme is further proposed to enable more flexible authentication. This solution covers the cases of authenticating the user even if some of the factors are mismatched or absent. Our framework allows for qualifying the missing factors by authenticating the user without disclosing sensitive biometric data to the verification entity. Finally, a vision of the future trends in MFA is discussed. Full article