Research on Anonymization and De-Anonymization in the Bitcoin System
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Money Laundering Using Cryptocurrency: the Case of Bitcoin!
Athens Journal of Law - Volume 7, Issue 2, April 2021 – Pages 253-264 Money Laundering using Cryptocurrency: The Case of Bitcoin! By Gaspare Jucan Sicignano* The bitcoin, one of the most discussed topics in recent years, is a virtual currency with enormous potential and can be used almost immediately with no intervention from financial institutions. It has spread rapidly over the last few years, and all financial and governmental institutions have warned of the risk of its use for money laundering. The paper focuses on this aspect in order to understand if any purchases of bitcoins, using illicit money, can come under the anti-money laundering criminal law. Keywords: Bitcoin; Money laundering; Italian law; Cryptocurrency. Introduction The bitcoin1 is a virtual, decentralised and partially anonymous currency based on cryptography and peer-to-peer technology2. With bitcoins it is possible to buy any type of good or service securely and rapidly. Transactions need not be authorised by a central entity; rather, they are validated by all users of the platform. The system is totally secure, since it is practically impossible to hack the protocol3. Bitcoin has been much criticised over the last few years; it has quickly become public enemy number one for everything from financing terrorism to drug dealing to money laundering. It has also recently been said that bitcoin would pollute the planet due to the resources required for mining4. This paper will attempt to analyse in depth the relationship between the bitcoin and money laundering in Italian law. It will analyse the warnings issued by authorities in various sectors, as well as the opinions expressed in Italian legal literature regarding the possibility of committing money laundering and self- laundering crimes in various operations carried out using virtual currency. -
Asymmetric Proof-Of-Work Based on the Generalized Birthday Problem
Equihash: Asymmetric Proof-of-Work Based on the Generalized Birthday Problem Alex Biryukov Dmitry Khovratovich University of Luxembourg University of Luxembourg [email protected] [email protected] Abstract—The proof-of-work is a central concept in modern Long before the rise of Bitcoin it was realized [20] that cryptocurrencies and denial-of-service protection tools, but the the dedicated hardware can produce a proof-of-work much requirement for fast verification so far made it an easy prey for faster and cheaper than a regular desktop or laptop. Thus the GPU-, ASIC-, and botnet-equipped users. The attempts to rely on users equipped with such hardware have an advantage over memory-intensive computations in order to remedy the disparity others, which eventually led the Bitcoin mining to concentrate between architectures have resulted in slow or broken schemes. in a few hardware farms of enormous size and high electricity In this paper we solve this open problem and show how to consumption. An advantage of the same order of magnitude construct an asymmetric proof-of-work (PoW) based on a compu- is given to “owners” of large botnets, which nowadays often tationally hard problem, which requires a lot of memory to gen- accommodate hundreds of thousands of machines. For prac- erate a proof (called ”memory-hardness” feature) but is instant tical DoS protection, this means that the early TLS puzzle to verify. Our primary proposal Equihash is a PoW based on the schemes [8], [17] are no longer effective against the most generalized birthday problem and enhanced Wagner’s algorithm powerful adversaries. -
Piecework: Generalized Outsourcing Control for Proofs of Work
(Short Paper): PieceWork: Generalized Outsourcing Control for Proofs of Work Philip Daian1, Ittay Eyal1, Ari Juels2, and Emin G¨unSirer1 1 Department of Computer Science, Cornell University, [email protected],[email protected],[email protected] 2 Jacobs Technion-Cornell Institute, Cornell Tech [email protected] Abstract. Most prominent cryptocurrencies utilize proof of work (PoW) to secure their operation, yet PoW suffers from two key undesirable prop- erties. First, the work done is generally wasted, not useful for anything but the gleaned security of the cryptocurrency. Second, PoW is natu- rally outsourceable, leading to inegalitarian concentration of power in the hands of few so-called pools that command large portions of the system's computation power. We introduce a general approach to constructing PoW called PieceWork that tackles both issues. In essence, PieceWork allows for a configurable fraction of PoW computation to be outsourced to workers. Its controlled outsourcing allows for reusing the work towards additional goals such as spam prevention and DoS mitigation, thereby reducing PoW waste. Meanwhile, PieceWork can be tuned to prevent excessive outsourcing. Doing so causes pool operation to be significantly more costly than today. This disincentivizes aggregation of work in mining pools. 1 Introduction Distributed cryptocurrencies such as Bitcoin [18] rely on the equivalence \com- putation = money." To generate a batch of coins, clients in a distributed cryp- tocurrency system perform an operation called mining. Mining requires solving a computationally intensive problem involving repeated cryptographic hashing. Such problem and its solution is called a Proof of Work (PoW) [11]. As currently designed, nearly all PoWs suffer from one of two drawbacks (or both, as in Bitcoin). -
Short Selling Attack: a Self-Destructive but Profitable 51% Attack on Pos Blockchains
Short Selling Attack: A Self-Destructive But Profitable 51% Attack On PoS Blockchains Suhyeon Lee and Seungjoo Kim CIST (Center for Information Security Technologies), Korea University, Korea Abstract—There have been several 51% attacks on Proof-of- With a PoS, the attacker needs to obtain 51% of the Work (PoW) blockchains recently, including Verge and Game- cryptocurrency to carry out a 51% attack. But unlike PoW, Credits, but the most noteworthy has been the attack that saw attacker in a PoS system is highly discouraged from launching hackers make off with up to $18 million after a successful double spend was executed on the Bitcoin Gold network. For this reason, 51% attack because he would have to risk of depreciation the Proof-of-Stake (PoS) algorithm, which already has advantages of his entire stake amount to do so. In comparison, bad of energy efficiency and throughput, is attracting attention as an actor in a PoW system will not lose their expensive alternative to the PoW algorithm. With a PoS, the attacker needs mining equipment if he launch a 51% attack. Moreover, to obtain 51% of the cryptocurrency to carry out a 51% attack. even if a 51% attack succeeds, the value of PoS-based But unlike PoW, attacker in a PoS system is highly discouraged from launching 51% attack because he would have to risk losing cryptocurrency will fall, and the attacker with the most stake his entire stake amount to do so. Moreover, even if a 51% attack will eventually lose the most. For these reasons, those who succeeds, the value of PoS-based cryptocurrency will fall, and attempt to attack 51% of the PoS blockchain will not be the attacker with the most stake will eventually lose the most. -
Blockchain & Cryptocurrency Regulation
Blockchain & Cryptocurrency Regulation Third Edition Contributing Editor: Josias N. Dewey Global Legal Insights Blockchain & Cryptocurrency Regulation 2021, Third Edition Contributing Editor: Josias N. Dewey Published by Global Legal Group GLOBAL LEGAL INSIGHTS – BLOCKCHAIN & CRYPTOCURRENCY REGULATION 2021, THIRD EDITION Contributing Editor Josias N. Dewey, Holland & Knight LLP Head of Production Suzie Levy Senior Editor Sam Friend Sub Editor Megan Hylton Consulting Group Publisher Rory Smith Chief Media Officer Fraser Allan We are extremely grateful for all contributions to this edition. Special thanks are reserved for Josias N. Dewey of Holland & Knight LLP for all of his assistance. Published by Global Legal Group Ltd. 59 Tanner Street, London SE1 3PL, United Kingdom Tel: +44 207 367 0720 / URL: www.glgroup.co.uk Copyright © 2020 Global Legal Group Ltd. All rights reserved No photocopying ISBN 978-1-83918-077-4 ISSN 2631-2999 This publication is for general information purposes only. It does not purport to provide comprehensive full legal or other advice. Global Legal Group Ltd. and the contributors accept no responsibility for losses that may arise from reliance upon information contained in this publication. This publication is intended to give an indication of legal issues upon which you may need advice. Full legal advice should be taken from a qualified professional when dealing with specific situations. The information contained herein is accurate as of the date of publication. Printed and bound by TJ International, Trecerus Industrial Estate, Padstow, Cornwall, PL28 8RW October 2020 PREFACE nother year has passed and virtual currency and other blockchain-based digital assets continue to attract the attention of policymakers across the globe. -
Does the Hashrate Affect the Bitcoin Price?
Journal of Risk and Financial Management Article Does the Hashrate Affect the Bitcoin Price? Dean Fantazzini 1,* and Nikita Kolodin 2 1 Moscow School of Economics, Moscow State University, Leninskie Gory, 1, Building 61, Moscow 119992, Russia 2 Higher School of Economics, Moscow 109028, Russia; [email protected] * Correspondence: [email protected]; Tel.: +7-4955105267; Fax: +7-4955105256 Received: 30 September 2020; Accepted: 27 October 2020; Published: 30 October 2020 Abstract: This paper investigates the relationship between the bitcoin price and the hashrate by disentangling the effects of the energy efficiency of the bitcoin mining equipment, bitcoin halving, and of structural breaks on the price dynamics. For this purpose, we propose a methodology based on exponential smoothing to model the dynamics of the Bitcoin network energy efficiency. We consider either directly the hashrate or the bitcoin cost-of-production model (CPM) as a proxy for the hashrate, to take any nonlinearity into account. In the first examined subsample (01/08/2016–04/12/2017), the hashrate and the CPMs were never significant, while a significant cointegration relationship was found in the second subsample (11/12/2017–24/02/2020). The empirical evidence shows that it is better to consider the hashrate directly rather than its proxy represented by the CPM when modeling its relationship with the bitcoin price. Moreover, the causality is always unidirectional going from the bitcoin price to the hashrate (or its proxies), with lags ranging from one week up to six weeks later. These findings are consistent with a large literature in energy economics, which showed that oil and gas returns affect the purchase of the drilling rigs with a delay of up to three months, whereas the impact of changes in the rig count on oil and gas returns is limited or not significant. -
Blockchain and Cryptocurrency in Africa a Comparative Summary of the Reception and Regulation of Blockchain and Cryptocurrency in Africa
Blockchain and Cryptocurrency in Africa A comparative summary of the reception and regulation of Blockchain and Cryptocurrency in Africa 2018 Baker McKenzie, Johannesburg IMPORTANT DISCLAIMER: The material in this report is of the nature of general comment only. It is not offered as legal advice on any specific issue or matter and should not be taken as such. Readers should refrain from acting on the basis of any discussion contained in this report without obtaining specific legal advice on the particular facts and circumstances at issue. While the authors have made every effort to provide accurate and up-to-date information on laws and policy, these matters are continuously subject to change. Furthermore, the application of these laws depends on the particular facts and circumstances of each situation, and therefore readers should consult their lawyer before taking any action. Information contained herein is as at November 2018. CONTENTS PREFACE ............................................................................................................................................1 GEOGRAPHICAL OVERVIEW ....................................................................................................... 2 COUNTRY PROFILES ..................................................................................................................... 3 1. Botswana ................................................................................................................................................................... 3 2. Ghana .........................................................................................................................................................................4 -
How to Not Get Caught When You Launder Money on Blockchain?
How to Not Get Caught When You Launder Money on Blockchain? Cuneyt G. Akcora1, Sudhanva Purusotham2, Yulia R. Gel2 Mitchell Krawiec-Thayer3, Murat Kantarcioglu2 1University of Manitoba, 2 UT Dallas, 3 Monero Research Lab 65 Chancellor Circle Winnipeg, MB, Canada R3T 2N2 [email protected], fSudhanva.Purushotham, ygl, [email protected], [email protected] Abstract transactions and circumvent existing AI-based money laun- dering techniques. Our insights, however, are intended not to The number of blockchain users has tremendously grown in assist criminals to obfuscate their malicious activities but to recent years. As an unintended consequence, e-crime trans- motivate the AI community for further research in this area actions on blockchains has been on the rise. Consequently, public blockchains have become a hotbed of research for de- of critical societal importance and, as a result, to advance veloping AI tools to detect and trace users and transactions the state of art methodology in the AI-based cryptocurrency that are related to e-crime. money laundering detection. We argue that following a few select strategies can make In the remainder of this paper, we first identify tech- money laundering on blockchain virtually undetectable with niques that can be used by criminals to launder money on most of the currently existing tools and algorithms. As a re- blockchain and then empirically show why these techniques sult, the effective combating of e-crime activities involving would be effective in hiding patterns used by potential AI cryptocurrencies requires the development of novel analytic models. methodology in AI. 2 Related Work 1 Introduction The success of Bitcoin (Nakamoto 2008) has encouraged Cryptocurrencies have emerged as an important rapidly hundreds of similar digital coins (Tschorsch and Scheuer- evolving financial tool that allows for cross-border transac- mann 2016). -
Coinbase Explores Crypto ETF (9/6) Coinbase Spoke to Asset Manager Blackrock About Creating a Crypto ETF, Business Insider Reports
Crypto Week in Review (9/1-9/7) Goldman Sachs CFO Denies Crypto Strategy Shift (9/6) GS CFO Marty Chavez addressed claims from an unsubstantiated report earlier this week that the firm may be delaying previous plans to open a crypto trading desk, calling the report “fake news”. Coinbase Explores Crypto ETF (9/6) Coinbase spoke to asset manager BlackRock about creating a crypto ETF, Business Insider reports. While the current status of the discussions is unclear, BlackRock is said to have “no interest in being a crypto fund issuer,” and SEC approval in the near term remains uncertain. Looking ahead, the Wednesday confirmation of Trump nominee Elad Roisman has the potential to tip the scales towards a more favorable cryptoasset approach. Twitter CEO Comments on Blockchain (9/5) Twitter CEO Jack Dorsey, speaking in a congressional hearing, indicated that blockchain technology could prove useful for “distributed trust and distributed enforcement.” The platform, given its struggles with how best to address fraud, harassment, and other misuse, could be a prime testing ground for decentralized identity solutions. Ripio Facilitates Peer-to-Peer Loans (9/5) Ripio began to facilitate blockchain powered peer-to-peer loans, available to wallet users in Argentina, Mexico, and Brazil. The loans, which utilize the Ripple Credit Network (RCN) token, are funded in RCN and dispensed to users in fiat through a network of local partners. Since all details of the loan and payments are recorded on the Ethereum blockchain, the solution could contribute to wider access to credit for the unbanked. IBM’s Payment Protocol Out of Beta (9/4) Blockchain World Wire, a global blockchain based payments network by IBM, is out of beta, CoinDesk reports. -
Bitcoin and Cryptocurrencies Law Enforcement Investigative Guide
2018-46528652 Regional Organized Crime Information Center Special Research Report Bitcoin and Cryptocurrencies Law Enforcement Investigative Guide Ref # 8091-4ee9-ae43-3d3759fc46fb 2018-46528652 Regional Organized Crime Information Center Special Research Report Bitcoin and Cryptocurrencies Law Enforcement Investigative Guide verybody’s heard about Bitcoin by now. How the value of this new virtual currency wildly swings with the latest industry news or even rumors. Criminals use Bitcoin for money laundering and other Enefarious activities because they think it can’t be traced and can be used with anonymity. How speculators are making millions dealing in this trend or fad that seems more like fanciful digital technology than real paper money or currency. Some critics call Bitcoin a scam in and of itself, a new high-tech vehicle for bilking the masses. But what are the facts? What exactly is Bitcoin and how is it regulated? How can criminal investigators track its usage and use transactions as evidence of money laundering or other financial crimes? Is Bitcoin itself fraudulent? Ref # 8091-4ee9-ae43-3d3759fc46fb 2018-46528652 Bitcoin Basics Law Enforcement Needs to Know About Cryptocurrencies aw enforcement will need to gain at least a basic Bitcoins was determined by its creator (a person Lunderstanding of cyptocurrencies because or entity known only as Satoshi Nakamoto) and criminals are using cryptocurrencies to launder money is controlled by its inherent formula or algorithm. and make transactions contrary to law, many of them The total possible number of Bitcoins is 21 million, believing that cryptocurrencies cannot be tracked or estimated to be reached in the year 2140. -
Transparent and Collaborative Proof-Of-Work Consensus
StrongChain: Transparent and Collaborative Proof-of-Work Consensus Pawel Szalachowski, Daniël Reijsbergen, and Ivan Homoliak, Singapore University of Technology and Design (SUTD); Siwei Sun, Institute of Information Engineering and DCS Center, Chinese Academy of Sciences https://www.usenix.org/conference/usenixsecurity19/presentation/szalachowski This paper is included in the Proceedings of the 28th USENIX Security Symposium. August 14–16, 2019 • Santa Clara, CA, USA 978-1-939133-06-9 Open access to the Proceedings of the 28th USENIX Security Symposium is sponsored by USENIX. StrongChain: Transparent and Collaborative Proof-of-Work Consensus Pawel Szalachowski1 Daniel¨ Reijsbergen1 Ivan Homoliak1 Siwei Sun2;∗ 1Singapore University of Technology and Design (SUTD) 2Institute of Information Engineering and DCS Center, Chinese Academy of Sciences Abstract a cryptographically-protected append-only list [2] is intro- duced. This list consists of transactions grouped into blocks Bitcoin is the most successful cryptocurrency so far. This and is usually referred to as a blockchain. Every active pro- is mainly due to its novel consensus algorithm, which is tocol participant (called a miner) collects transactions sent based on proof-of-work combined with a cryptographically- by users and tries to solve a computationally-hard puzzle in protected data structure and a rewarding scheme that incen- order to be able to write to the blockchain (the process of tivizes nodes to participate. However, despite its unprece- solving the puzzle is called mining). When a valid solution dented success Bitcoin suffers from many inefficiencies. For is found, it is disseminated along with the transactions that instance, Bitcoin’s consensus mechanism has been proved to the miner wishes to append. -
3Rd Global Cryptoasset Benchmarking Study
3RD GLOBAL CRYPTOASSET BENCHMARKING STUDY Apolline Blandin, Dr. Gina Pieters, Yue Wu, Thomas Eisermann, Anton Dek, Sean Taylor, Damaris Njoki September 2020 supported by Disclaimer: Data for this report has been gathered primarily from online surveys. While every reasonable effort has been made to verify the accuracy of the data collected, the research team cannot exclude potential errors and omissions. This report should not be considered to provide legal or investment advice. Opinions expressed in this report reflect those of the authors and not necessarily those of their respective institutions. TABLE OF CONTENTS FOREWORDS ..................................................................................................................................................4 RESEARCH TEAM ..........................................................................................................................................6 ACKNOWLEDGEMENTS ............................................................................................................................7 EXECUTIVE SUMMARY ........................................................................................................................... 11 METHODOLOGY ........................................................................................................................................ 14 SECTION 1: INDUSTRY GROWTH INDICATORS .........................................................................17 Employment figures ..............................................................................................................................................................................................................17