Short Selling Attack: a Self-Destructive but Profitable 51% Attack on Pos Blockchains
Total Page:16
File Type:pdf, Size:1020Kb
Load more
Recommended publications
-
Casper the Friendly Finality Gadget
Casper the Friendly Finality Gadget Vitalik Buterin and Virgil Griffith Ethereum Foundation Abstract We introduce Casper, a proof of stake-based finality system which overlays an existing proof of work blockchain. Casper is a partial consensus mechanism combining proof of stake algorithm research and Byzantine fault tolerant consensus theory. We introduce our system, prove some desirable features, and show defenses against long range revisions and catastrophic crashes. The Casper overlay provides almost any proof of work chain with additional protections against block reversions. 1. Introduction Over the past few years there has been considerable research into “proof of stake” (PoS) based blockchain consensus algorithms. In a PoS system, a blockchain appends and agrees on new blocks through a process where anyone who holds coins inside of the system can participate, and the influence an agent has is proportional to the number of coins (or “stake”) it holds. This is a vastly more efficient alternative to proof of work (PoW) “mining” and enables blockchains to operate without mining’s high hardware and electricity costs. There are two major schools of thought in PoS design. The first, chain-based proof of stake[1, 2], mimics proof of work mechanics and features a chain of blocks and simulates mining by pseudorandomly assigning the right to create new blocks to stakeholders. This includes Peercoin[3], Blackcoin[4], and Iddo Bentov’s work[5]. The other school, Byzantine fault tolerant (BFT) based proof of stake, is based on a thirty-year-old body of research into BFT consensus algorithms such as PBFT[6]. BFT algorithms typically have proven mathematical 2 properties; for example, one can usually mathematically prove that as long as > 3 of protocol participants are following the protocol honestly, then, regardless of network latency, the algorithm cannot finalize conflicting blocks. -
Beauty Is Not in the Eye of the Beholder
Insight Consumer and Wealth Management Digital Assets: Beauty Is Not in the Eye of the Beholder Parsing the Beauty from the Beast. Investment Strategy Group | June 2021 Sharmin Mossavar-Rahmani Chief Investment Officer Investment Strategy Group Goldman Sachs The co-authors give special thanks to: Farshid Asl Managing Director Matheus Dibo Shahz Khatri Vice President Vice President Brett Nelson Managing Director Michael Murdoch Vice President Jakub Duda Shep Moore-Berg Harm Zebregs Vice President Vice President Vice President Shivani Gupta Analyst Oussama Fatri Yousra Zerouali Vice President Analyst ISG material represents the views of ISG in Consumer and Wealth Management (“CWM”) of GS. It is not financial research or a product of GS Global Investment Research (“GIR”) and may vary significantly from those expressed by individual portfolio management teams within CWM, or other groups at Goldman Sachs. 2021 INSIGHT Dear Clients, There has been enormous change in the world of cryptocurrencies and blockchain technology since we first wrote about it in 2017. The number of cryptocurrencies has increased from about 2,000, with a market capitalization of over $200 billion in late 2017, to over 8,000, with a market capitalization of about $1.6 trillion. For context, the market capitalization of global equities is about $110 trillion, that of the S&P 500 stocks is $35 trillion and that of US Treasuries is $22 trillion. Reported trading volume in cryptocurrencies, as represented by the two largest cryptocurrencies by market capitalization, has increased sixfold, from an estimated $6.8 billion per day in late 2017 to $48.6 billion per day in May 2021.1 This data is based on what is called “clean data” from Coin Metrics; the total reported trading volume is significantly higher, but much of it is artificially inflated.2,3 For context, trading volume on US equity exchanges doubled over the same period. -
Validation of Smart Contracts Through Automated Tooling
Faculty of Sciences and Tecnology Department of Informatics Engineering Validation of Smart Contracts Through Automated Tooling Tom´asMorgado de Carvalho Concei¸c~ao Internship Report in the context of the Master in Informatics Engineering, Specialization in Software Engineering advised by Professor Raul Barbosa and Eng. Jo~aoBarbosa and presented to the Department of Informatics Engineering / Faculty of Sciences and Technology January 2019 Acknowledgements I would first like to thank Professor Raul Barbosa, my advisor at the University of Coimbra, for, with his valuable experience and insights, guiding me through this process and always challenging me to do better. I would like to thank my advisor, Jo~aoBarbosa, not only for his technical contributions to this dissertation but for always ensuring that I had my priorities straight and was managing my time properly. Thank you for pushing me to always make healthy choices regarding my work-life balance. I want to thank the members of my jury, Professor Fernando Jos´eBarros and Professor C´esarAlexandre Domingues Teixeira, for their input and suggestions for improvement, and their constructive criticism. I would like to thank Whitesmith and Blocksmith, and in particular Gon¸caloLouzada, Maria Jo~aoFerreira and Rafael Jegundo, for accepting me on this internship, providing me with all the tools and conditions to achieve my goals and for inviting me to take part on other projects during this year. I would also like to thank my co-workers, who, since the first day and without exception, made me feel welcome and at home. I have learned something new with every single one of you. -
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). -
Consent Order: HDR Global Trading Limited, Et Al
Case 1:20-cv-08132-MKV Document 62 Filed 08/10/21 Page 1 of 22 UNITED STATES DISTRICT COURT SOUTHERN DISTRICT OF NEW YORK USDC SDNY DOCUMENT ELECTRONICALLY FILED COMMODITY FUTURES TRADING DOC #: COMMISSION, DATE FILED: 8/10/2021 Plaintiff v. Case No. 1:20-cv-08132 HDR GLOBAL TRADING LIMITED, 100x Hon. Mary Kay Vyskocil HOLDINGS LIMITED, ABS GLOBAL TRADING LIMITED, SHINE EFFORT INC LIMITED, HDR GLOBAL SERVICES (BERMUDA) LIMITED, ARTHUR HAYES, BENJAMIN DELO, and SAMUEL REED, Defendants CONSENT ORDER FOR PERMANENT INJUNCTION, CIVIL MONETARY PENALTY, AND OTHER EQUITABLE RELIEF AGAINST DEFENDANTS HDR GLOBAL TRADING LIMITED, 100x HOLDINGS LIMITED, SHINE EFFORT INC LIMITED, and HDR GLOBAL SERVICES (BERMUDA) LIMITED I. INTRODUCTION On October 1, 2020, Plaintiff Commodity Futures Trading Commission (“Commission” or “CFTC”) filed a Complaint against Defendants HDR Global Trading Limited (“HDR”), 100x Holdings Limited (100x”), ABS Global Trading Limited (“ABS”), Shine Effort Inc Limited (“Shine”), and HDR Global Services (Bermuda) Limited (“HDR Services”), all doing business as “BitMEX” (collectively “BitMEX”) as well as BitMEX’s co-founders Arthur Hayes (“Hayes”), Benjamin Delo (“Delo”), and Samuel Reed (“Reed”), (collectively “Defendants”), seeking injunctive and other equitable relief, as well as the imposition of civil penalties, for violations of the Commodity Exchange Act (“Act”), 7 U.S.C. §§ 1–26 (2018), and the Case 1:20-cv-08132-MKV Document 62 Filed 08/10/21 Page 2 of 22 Commission’s Regulations (“Regulations”) promulgated thereunder, 17 C.F.R. pts. 1–190 (2020). (“Complaint,” ECF No. 1.)1 II. CONSENTS AND AGREEMENTS To effect settlement of all charges alleged in the Complaint against Defendants HDR, 100x, ABS, Shine, and HDR Services (“Settling Defendants”) without a trial on the merits or any further judicial proceedings, Settling Defendants: 1. -
Bitmex Xbt Price on Spreadsheet
Bitmex Xbt Price On Spreadsheet Follow-up Barty sometimes enounces his Beaulieu stalwartly and configure so apologetically! If unteachable or goadSolutrean her Stafford Troy usually insufferably, risks his Salopian roneos prickle and uniplanar. amok or solemnized proximo and farther, how piniest is Zeb? Uli BitMEX Topics covered in Lesson 2 Cash an Carry. Bitmex Bans Its sister Country Trustnodes. Bitmex XBTUSD historical price data order books and OHLCV candlesticks. American authorities police criminal charges on Thursday against the owners of kiss of surgery world's biggest cryptocurrency trading exchanges BitMEX accusing them of allowing the Hong Kong-based company to launder money and engage in other illegal transactions. This call does return Bitcoin traded volume in XBT over since last 24h on Kraken. The Calculator can show his current ProfitLoss PnL Target prices at set. 6 July 2019 AntiLiquidation is a BitMEX Anti-Liquidation Tool Position Calculator. 24 Hours BitMex Liquidation Data of XBTUSD ETHUSD and All Supported Asset. BTC USD Bitfinex Historical Data Investingcom. It is Buyer's move bitcoin analysis price bitmex inverse contract process are playing. For market trades fees are 0075 of your stop for both entry exit So total fees on a 1000 trade with 100x leverage are 150 100 x 1000 x 000075 x 2 Fees are 15 in industry case. Bitcoin Price Bitmex and Coinbase Trading News Value of Wallet Bitcoin. In a dramatic day for Bitcoin BTC bulls pushed the price of BitMEX's XBT. Demo Binance Huobi Bitmex And Others In Spreadsheet Using Api Excel. The price on an ma in any such levels indicator would come under cftc. -
Creation and Resilience of Decentralized Brands: Bitcoin & The
Creation and Resilience of Decentralized Brands: Bitcoin & the Blockchain Syeda Mariam Humayun A dissertation submitted to the Faculty of Graduate Studies in partial fulfillment of the requirements for the degree of Doctor of Philosophy Graduate Program in Administration Schulich School of Business York University Toronto, Ontario March 2019 © Syeda Mariam Humayun 2019 Abstract: This dissertation is based on a longitudinal ethnographic and netnographic study of the Bitcoin and broader Blockchain community. The data is drawn from 38 in-depth interviews and 200+ informal interviews, plus archival news media sources, netnography, and participant observation conducted in multiple cities: Toronto, Amsterdam, Berlin, Miami, New York, Prague, San Francisco, Cancun, Boston/Cambridge, and Tokyo. Participation at Bitcoin/Blockchain conferences included: Consensus Conference New York, North American Bitcoin Conference, Satoshi Roundtable Cancun, MIT Business of Blockchain, and Scaling Bitcoin Tokyo. The research fieldwork was conducted between 2014-2018. The dissertation is structured as three papers: - “Satoshi is Dead. Long Live Satoshi.” The Curious Case of Bitcoin: This paper focuses on the myth of anonymity and how by remaining anonymous, Satoshi Nakamoto, was able to leave his creation open to widespread adoption. - Tracing the United Nodes of Bitcoin: This paper examines the intersection of religiosity, technology, and money in the Bitcoin community. - Our Brand Is Crisis: Creation and Resilience of Decentralized Brands – Bitcoin & the Blockchain: Drawing on ecological resilience framework as a conceptual metaphor this paper maps how various stabilizing and destabilizing forces in the Bitcoin ecosystem helped in the evolution of a decentralized brand and promulgated more mainstreaming of the Bitcoin brand. ii Dedication: To my younger brother, Umer. -
The Bitcoin Trading Ecosystem
ArcaneReport(PrintReady).qxp 21/07/2021 14:43 Page 1 THE INSTITUTIONAL CRYPTO CURRENCY EXCHANGE INSIDE FRONT COVER: BLANK ArcaneReport(PrintReady).qxp 21/07/2021 14:43 Page 3 The Bitcoin Trading Ecosystem Arcane Research LMAX Digital Arcane Research is a part of Arcane Crypto, bringing LMAX Digital is the leading institutional spot data-driven analysis and research to the cryptocurrency exchange, run by the LMAX Group, cryptocurrency space. After launch in August 2019, which also operates several leading FCA regulated Arcane Research has become a trusted brand, trading venues for FX, metals and indices. Based on helping clients strengthen their credibility and proven, proprietary technology from LMAX Group, visibility through research reports and analysis. In LMAX Digital allows global institutions to acquire, addition, we regularly publish reports, weekly market trade and hold the most liquid digital assets, Bitcoin, updates and articles to educate and share insights. Ethereum, Litecoin, Bitcoin Cash and XRP, safely and securely. Arcane Crypto develops and invests in projects, focusing on bitcoin and digital assets. Arcane Trading with all the largest institutions globally, operates a portfolio of businesses, spanning the LMAX Digital is a primary price discovery venue, value chain for digital nance. As a group, Arcane streaming real-time market data to the industry’s deliver services targeting payments, investment, and leading indices and analytics platforms, enhancing trading, in addition to a media and research leg. the quality of market information available to investors and enabling a credible overview of the Arcane has the ambition to become a leading player spot crypto currency market. in the digital assets space by growing the existing businesses, invest in cutting edge projects, and LMAX Digital is regulated by the Gibraltar Financial through acquisitions and consolidation. -
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. -
Bitflyer Raises Approximately JPY 130 Million in Funds
bitFlyer, Inc Yuzo Kano, CEO bitFlyer Raises JPY 130 million in Funds We are delighted to announce that bitFlyer (Company Headquarters: Chiyoda-ku, Tokyo, Yuzo Kano, CEO), in order to expand its comprehensive Bitcoin platform and marketplace, has closed a fundraising round of approximately JPY 130 million. We are pleased to have received an investment from several third party investment organizations, including the below (titles omitted, in no particular order): RSP Fund No. 5 (Headquarters: Chuo-ku, Tokyo, Akihiko Okamoto, President) GMO Venture Partners (Headquarters: Shibuya-ku, Tokyo, Masatoshi Kumagai, CEO) Bitcoin Opportunity Corp (Headquarters: New York, USA, Barry Silbert, CEO) The purpose of this funding will be to further strengthen our Bitcoin related businesses in the domestic as well as international markets, set up overseas offices, recruit new talent, accelerate service development, and carry out marketing and advertising campaigns to promote business growth. In addition, the synergies gained through close collaboration with our investment partners, customer base expansion, and the strengthening of our revenue base will help to facilitate our global business expansion. We will continue to pursue our primary goals of improving security while providing the best possible services to our customers. Thank you for using bitFlyer. Reference 1. Information Regarding our Investment Partners RSP Fund No. 5 RSP Fund No. 5 is a wholly owned subsidiary of Recruit Holdings, Co., Ltd. Headquartered in Tokyo and with offices in Silicon Valley, RSP invests in and provides management support to IT companies that provide innovative products and services around the world. GMO Venture Partners GMO Venture Partners is the venture capital arm of GMO Internet Group, investing more than JPY 5 billion to 51 companies in total, including 8 listed companies.