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

Investigation related to multispectral imaging systems

A summary of technical progress made during a five year research program directed toward the development of operational information systems based on multispectral sensing and the use of these systems in earth-resource survey applications is presented. Efforts were undertaken during this program to: (1) improve the basic understanding of the many facets of multispectral remote sensing, (2) develop methods for improving the accuracy of information generated by remote sensing systems, (3) improve the efficiency of data processing and information extraction techniques to enhance the cost-effectiveness of remote sensing systems, (4) investigate additional problems having potential remote sensing solutions, and (5) apply the existing and developing technology for specific users and document and transfer that technology to the remote sensing community

Proceedings of the Airborne Imaging Spectrometer Data Analysis Workshop

The Airborne Imaging Spectrometer (AIS) Data Analysis Workshop was held at the Jet Propulsion Laboratory on April 8 to 10, 1985. It was attended by 92 people who heard reports on 30 investigations currently under way using AIS data that have been collected over the past two years. Written summaries of 27 of the presentations are in these Proceedings. Many of the results presented at the Workshop are preliminary because most investigators have been working with this fundamentally new type of data for only a relatively short time. Nevertheless, several conclusions can be drawn from the Workshop presentations concerning the value of imaging spectrometry to Earth remote sensing. First, work with AIS has shown that direct identification of minerals through high spectral resolution imaging is a reality for a wide range of materials and geological settings. Second, there are strong indications that high spectral resolution remote sensing will enhance the ability to map vegetation species. There are also good indications that imaging spectrometry will be useful for biochemical studies of vegetation. Finally, there are a number of new data analysis techniques under development which should lead to more efficient and complete information extraction from imaging spectrometer data. The results of the Workshop indicate that as experience is gained with this new class of data, and as new analysis methodologies are developed and applied, the value of imaging spectrometry should increase

Secure electronic commerce with mobile agents

Online transactions using mobile agents need secure protocols to help the mobile agents to accomplish the transactions initiated by a client in an electronic commerce. However, the mobile agent could encounter hostile environment. For example, a server may compromise the mobile agent and try to obtain private information of the client. A solution to tackle this issue has been proposed. However, the existing solution is implemented using RSA signatures that result in long signatures and heavy workloads for the mobile agent. Mobile agents will migrate from the client to a server and from one server to other servers in order to accomplish the client?s transaction plan. Therefore, it will be interesting to re-tackle this issue. We present a new scheme for secure transactions using mobile agents in potentially hostile environments. This transaction scheme is implemented by using a new undetachable signature scheme. The new undetachable signature protocol utilizes short signatures, which is desirable for low-bandwidth and efficient mobile communications

Secure e-transactions using mobile agents with agent broker

This paper presents an e-transactions protocol using mobile agents. However, when mobile agents travel to a number of servers for searching optimal purchase for the underlying customer, the mobile codes should be protected. We integrate a secure signature algorithm with the e-transaction algorithm to maintain the security. In addition, an agent broker is involved in the algorithm that will help to reduce the communications among the mobile agents, the customer, and the servers. We have presented security and privacy analysis for the proposed protocol

Utilizing Computational Complexity to Protect Cryptocurrency against Quantum Threats: A Review

Digital currency is primarily designed on problems that are computationally hard to solve using traditional computing techniques. However, these problems are now vulnerable due to the computational power of quantum computing. For the postquantum computing era, there is an immense need to reinvent the existing digital security measures. Problems that are computationally hard for any quantum computation will be a possible solution to that. This research summarizes the current security measures and how the new way of solving hard problems will trigger the future protection of the existing digital currency from the future quantum threat

Generic Attacks and the Security of Quartz

Abstract. The signature scheme Quartz is based on a trapdoor function G that be-longs to a family called HFEv-. This function has the advantage to have two indepen-dent security parameters, and we claim that if d is big enough, no better method to compute an inverse of G than the exhaustive search is known. This paper looks at the security of Quartz under this (quite a strong) assumption. It allows a generic approach to the security of Quartz. We view it as a special case of a general construction called generalized Feistel-Patarin scheme, that transforms a trapdoor function into a short signature scheme. The main object of this paper is the concrete security of this general construction. On one hand, we present generic attacks on such schemes. On the other hand, we study the possibility to prove or justify the security with some well chosen assumptions. Unfortunately for Quartz, our lower and upper security bounds do not coincide. Still the best attack known for Quartz is our generic attack using O(280) computations with O(280) of memory. We will also propose an alternative way of doing short signatures, less general than the Feistel-Patarin scheme, but for which both bounds do coincide