Quantum attacks on Bitcoin, and how to protect against them

The key cryptographic protocols used to secure the internet and financial transactions of today are all susceptible to attack by the development of a sufficiently large quantum computer. One particular area at risk are cryptocurrencies, a market currently worth over 150 billion USD. We investigate the risk of Bitcoin, and other cryptocurrencies, to attacks by quantum computers. We find that the proof-of-work used by Bitcoin is relatively resistant to substantial speedup by quantum computers in the next 10 years, mainly because specialized ASIC miners are extremely fast compared to the estimated clock speed of near-term quantum computers. On the other hand, the elliptic curve signature scheme used by Bitcoin is much more at risk, and could be completely broken by a quantum computer as early as 2027, by the most optimistic estimates. We analyze an alternative proof-of-work called Momentum, based on finding collisions in a hash function, that is even more resistant to speedup by a quantum computer. We also review the available post-quantum signature schemes to see which one would best meet the security and efficiency requirements of blockchain applications.Comment: 21 pages, 6 figures. For a rough update on the progress of Quantum devices and prognostications on time from now to break Digital signatures, see https://www.quantumcryptopocalypse.com/quantum-moores-law

Using quantum key distribution for cryptographic purposes: a survey

The appealing feature of quantum key distribution (QKD), from a cryptographic viewpoint, is the ability to prove the information-theoretic security (ITS) of the established keys. As a key establishment primitive, QKD however does not provide a standalone security service in its own: the secret keys established by QKD are in general then used by a subsequent cryptographic applications for which the requirements, the context of use and the security properties can vary. It is therefore important, in the perspective of integrating QKD in security infrastructures, to analyze how QKD can be combined with other cryptographic primitives. The purpose of this survey article, which is mostly centered on European research results, is to contribute to such an analysis. We first review and compare the properties of the existing key establishment techniques, QKD being one of them. We then study more specifically two generic scenarios related to the practical use of QKD in cryptographic infrastructures: 1) using QKD as a key renewal technique for a symmetric cipher over a point-to-point link; 2) using QKD in a network containing many users with the objective of offering any-to-any key establishment service. We discuss the constraints as well as the potential interest of using QKD in these contexts. We finally give an overview of challenges relative to the development of QKD technology that also constitute potential avenues for cryptographic research.Comment: Revised version of the SECOQC White Paper. Published in the special issue on QKD of TCS, Theoretical Computer Science (2014), pp. 62-8

Aspects of hardware methodologies for the NTRU public-key cryptosystem

Cryptographic algorithms which take into account requirements for varying levels of security and reduced power consumption in embedded devices are now receiving additional attention. The NTRUEncrypt algorithm has been shown to provide certain advantages when designing low power and resource constrained systems, while still providing comparable security levels to higher complexity algorithms. The research presented in this thesis starts with an examination of the general NTRUEncrypt system, followed by a more practical examination with respect to the IEEE 1363.1 draft standard. In contrast to previous research, the focus is shifted away from specific optimizations but rather provides a study of many of the recommended practices and suggested optimizations with particular emphasis on polynomial arithmetic and parameter selection. Various methods are examined for storing, inverting and multiplying polynomials used in the system. Recommendations for algorithm and parameter selection are made regarding implementation in software and hardware with respect to the resources available. Although the underlying mathematical principles have not been significantly questioned, stable recommended practices are still being developed for the NTRUEncrypt system. As a further complication, recommended optimizations have come from various researchers and have been split between hardware and software implementations. In this thesis, a generic VHDL model is presented, based on the IEEE 1363.1 draft standard, which is designed for adaptation to software or hardware implementation while providing flexibility for changes in recommended practices

A Survey on Wireless Sensor Network Security

Wireless sensor networks (WSNs) have recently attracted a lot of interest in the research community due their wide range of applications. Due to distributed nature of these networks and their deployment in remote areas, these networks are vulnerable to numerous security threats that can adversely affect their proper functioning. This problem is more critical if the network is deployed for some mission-critical applications such as in a tactical battlefield. Random failure of nodes is also very likely in real-life deployment scenarios. Due to resource constraints in the sensor nodes, traditional security mechanisms with large overhead of computation and communication are infeasible in WSNs. Security in sensor networks is, therefore, a particularly challenging task. This paper discusses the current state of the art in security mechanisms for WSNs. Various types of attacks are discussed and their countermeasures presented. A brief discussion on the future direction of research in WSN security is also included.Comment: 24 pages, 4 figures, 2 table

VANET SECURITY FRAMEWORK FOR LOW LATENCY SAFETY APPLICATIONS

Vehicular Ad hoc Network (VANET) is a communication network for vehicles on the road. The concept of VANET is to create communication between vehicles, such as one vehicle is able to inform another vehicle about the road conditions. Communication is possible by vehicle to vehicle (V2V) and vehicle to road side unit (V2R). Presently, VANET technology is surrounded with security challenges and it is essentially important for VANET to successfully implement a security measure according to the safety applications requirements. Many researchers have proposed a number of solutions to counter security attacks and also to improve certain aspects of security i.e. authentication, privacy, and non-repudiation. The current most suitable security scheme for VANET is an Elliptic Curve Digital Signature Algorithm (ECDSA) asymmetric security mechanism. ECDSA is small in key size but it provides the same level of security as the large key sized scheme. However ECDSA is associated with high computational cost, thus lacking applicability in life-critical safety messaging. Due to that reason, alternative security schemes have been proposed, such as symmetric methods which provide faster communication, but at the expense of reduced security. Hence, hybrid and hardware based solutions have been proposed by researchers to mitigate the issue. However, these solutions still do not satisfy the existing safety applications standard or have larger message size due to increased message drop ratio. In this thesis, a security framework is presented; one that uses both standard asymmetric PKI and symmetric cryptography for faster and secured safety message exchange. The proposed framework is expected to improve the security mechanism in VANET by developing trust relationship among the neighboring nodes, hence forming trusted groups. The trust is established via Trusted Platform Module (TPM) and group communication. In this study, the proposed framework methods are simulated using two propagation models, i.e. two ray ground model and Nakagami model for VANET environment (802.11p). In this simulation, two traffic scenarios such as highway and urban are established. The outcome of both simulation scenarios is analyzed to identify the performance of the proposed methods in terms of latency (End-to-End Delay and Processing Delay). Also, the proposed V2V protocol for a framework is validated using a software in order to establish trust among vehicles

FPGA Implementation of Post-Quantum Cryptography Recommended by NIST

In the next 10 to 50 years, the quantum computer is expected to be available and quantum computing has the potential to defeat RSA (Rivest-Shamir-Adleman Cryptosystem) and ECC (Elliptic Curve Cryptosystem). Therefore there is an urgentneed to do research on post-quantum cryptography and its implementation. In this thesis, four new Truncated Polynomial Multipliers (TPM), namely, TPM-I, TPM-II, TPM-III, and TPM-IV for NTRU Prime system are proposed. To the best of our knowledge, this is the first time to focus on time-efficient hardware architectures and implementation of NTRU Prime with FPGA. TPM-I uses a modified linear feedback shift register (LFSR) based architecture for NTRU prime system. TPM-II makes use of x^2-net structure for NTRU Prime system, which scans two consecutive coefficients in the control input polynomial r(x) in one clock cycle. In TPM-III and TPM-IV, three consecutive zeros and consecutive zeros in the control input polynomial r(x) are scanned during one clock cycle, respectively. FPGA implementation results are obtained for the four proposed polynomial multiplication architectures and a comparison between the proposed multiplier FPGA results for NTRU Prime system and the existing work on NTRUEncrypt is shown. Regarding space complexity, TPM-I can reduce the area consumption with the least logical elements, although it takes more latency time among the four proposed multipliers and NTRUEncrypt work [12]. TPM-II has the best performance of latency with parameter sets ees401ep1, ees449ep1, ees677ep1 in security levels: 112-bit, 128-bit, and 192-bit, respectively. TPM-IV uses the smallest latency time with the parameter set ees1087ep2 in security level 256, compared to the other three latency time of proposed multipliers. Both TPM-II and TPM-IV have a lower latency time compared to NTRUEncrypt work [12] in different security levels. Note that NTRU Prime has enhanced security in comparison with NTRUEncrypt due to the fact, the former uses a new truncated polynomial ring, which has a more secure structure

Survey on Lightweight Primitives and Protocols for RFID in Wireless Sensor Networks

The use of radio frequency identification (RFID) technologies is becoming widespread in all kind of wireless network-based applications. As expected, applications based on sensor networks, ad-hoc or mobile ad hoc networks (MANETs) can be highly benefited from the adoption of RFID solutions. There is a strong need to employ lightweight cryptographic primitives for many security applications because of the tight cost and constrained resource requirement of sensor based networks. This paper mainly focuses on the security analysis of lightweight protocols and algorithms proposed for the security of RFID systems. A large number of research solutions have been proposed to implement lightweight cryptographic primitives and protocols in sensor and RFID integration based resource constraint networks. In this work, an overview of the currently discussed lightweight primitives and their attributes has been done. These primitives and protocols have been compared based on gate equivalents (GEs), power, technology, strengths, weaknesses and attacks. Further, an integration of primitives and protocols is compared with the possibilities of their applications in practical scenarios

NTRU based group oriented signature

In order to prevent illegal tracking and stealing personal or cargo information, the authentication services should be provided for the tags to identify a Reader. A NTRU based signature scheme is proposed in this paper, which meets the demand for a group of tags to quickly and securely identify a Reader in RFID system. In our scheme, only the tag in specified group can verify the reader’s message. Because of fast operation, easy key generation and limited source occupied, our signature is very suit for the RFID systems