distributed ledger

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pages: 515 words: 126,820

Blockchain Revolution: How the Technology Behind Bitcoin Is Changing Money, Business, and the World by Don Tapscott, Alex Tapscott

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Airbnb, altcoin, asset-backed security, autonomous vehicles, barriers to entry, bitcoin, blockchain, Bretton Woods, business process, Capital in the Twenty-First Century by Thomas Piketty, carbon footprint, clean water, cloud computing, cognitive dissonance, corporate governance, corporate social responsibility, Credit Default Swap, crowdsourcing, cryptocurrency, disintermediation, distributed ledger, Donald Trump, double entry bookkeeping, Edward Snowden, Elon Musk, Erik Brynjolfsson, ethereum blockchain, failed state, fiat currency, financial innovation, Firefox, first square of the chessboard, first square of the chessboard / second half of the chessboard, future of work, Galaxy Zoo, George Gilder, glass ceiling, Google bus, Hernando de Soto, income inequality, informal economy, interest rate swap, Internet of things, Jeff Bezos, jimmy wales, Kickstarter, knowledge worker, Kodak vs Instagram, Lean Startup, litecoin, Lyft, M-Pesa, Mark Zuckerberg, Marshall McLuhan, means of production, microcredit, mobile money, Network effects, new economy, Oculus Rift, pattern recognition, peer-to-peer lending, performance metric, Peter Thiel, planetary scale, Ponzi scheme, prediction markets, price mechanism, Productivity paradox, quantitative easing, ransomware, Ray Kurzweil, renewable energy credits, rent-seeking, ride hailing / ride sharing, Ronald Coase, Ronald Reagan, Satoshi Nakamoto, Second Machine Age, seigniorage, self-driving car, sharing economy, Silicon Valley, Skype, smart contracts, smart grid, social graph, social software, Stephen Hawking, Steve Jobs, Steve Wozniak, Stewart Brand, supply-chain management, TaskRabbit, The Fortune at the Bottom of the Pyramid, The Nature of the Firm, The Wisdom of Crowds, transaction costs, Turing complete, Turing test, Uber and Lyft, unbanked and underbanked, underbanked, unorthodox policies, X Prize, Y2K, Zipcar

Each block must refer to the preceding block to be valid. This structure permanently time-stamps and stores exchanges of value, preventing anyone from altering the ledger. If you wanted to steal a bitcoin, you’d have to rewrite the coin’s entire history on the blockchain in broad daylight. That’s practically impossible. So the blockchain is a distributed ledger representing a network consensus of every transaction that has ever occurred. Like the World Wide Web of information, it’s the World Wide Ledger of value—a distributed ledger that everyone can download and run on their personal computer. Some scholars have argued that the invention of double-entry bookkeeping enabled the rise of capitalism and the nation-state. This new digital ledger of economic transactions can be programmed to record virtually everything of value and importance to humankind: birth and death certificates, marriage licenses, deeds and titles of ownership, educational degrees, financial accounts, medical procedures, insurance claims, votes, provenance of food, and anything else that can be expressed in code.

Peter Todd, “Re: [Bitcoin-development] Fwd: Block Size Increase Requirements,” The Mail Archive, June 1, 2015; www.mail-archive.com/, http://tinyurl.com/pk4ordw, accessed August 26, 2015. 44. Satoshi Nakamoto, “Re: Bitcoin P2P E-cash Paper,” Mailing List, Cryptography, Metzger, Dowdeswell & Co. LLC, November 11, 2008. Web. July 13, 2015, www.metzdowd.com/mailman/listinfo/cryptography. 45. Pascal Bouvier, “Distributed Ledgers Part I: Bitcoin Is Dead,” FiniCulture blog, August 4, 2015; http://finiculture.com/distributed-ledgers-part-i-bitcoin-is-dead/, accessed August 28, 2015. 46. Western Union, “Company Facts,” Western Union, Western Union Holdings, Inc., December 31, 2014. Web. January 13, 2016; http://corporate.westernunion.com/Corporate_Fact_Sheet.html. 47. Interview with Gavin Andresen, June 8, 2015. 48. Ibid. 49. Interview with Austin Hill, July 22, 2015. 50.

This has never happened before—trusted transactions directly between two or more parties, authenticated by mass collaboration and powered by collective self-interests, rather than by large corporations motivated by profit. It may not be the Almighty, but a trustworthy global platform for our transactions is something very big. We’re calling it the Trust Protocol. This protocol is the foundation of a growing number of global distributed ledgers called blockchains—of which the bitcoin blockchain is the largest. While the technology is complicated and the word blockchain isn’t exactly sonorous, the main idea is simple. Blockchains enable us to send money directly and safely from me to you, without going through a bank, a credit card company, or PayPal. Rather than the Internet of Information, it’s the Internet of Value or of Money.


pages: 161 words: 44,488

The Business Blockchain: Promise, Practice, and Application of the Next Internet Technology by William Mougayar

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Airbnb, airport security, Albert Einstein, altcoin, Amazon Web Services, bitcoin, Black Swan, blockchain, business process, centralized clearinghouse, Clayton Christensen, cloud computing, cryptocurrency, disintermediation, distributed ledger, Edward Snowden, en.wikipedia.org, ethereum blockchain, fault tolerance, fiat currency, global value chain, Innovator's Dilemma, Internet of things, Kevin Kelly, Kickstarter, market clearing, Network effects, new economy, peer-to-peer lending, prediction markets, pull request, ride hailing / ride sharing, Satoshi Nakamoto, sharing economy, smart contracts, social web, software as a service, too big to fail, Turing complete, web application

Programs written in Smart Contract Language get compiled into the Virtual Machine, and to create the contracts you send the transaction containing your code. Historical Record Transactions are actually recorded in sequential data blocks (hence the word blockchain), so there is a historical, append-only log of these transactions that is continuously maintained and updated. A fallacy is that the blockchain is a distributed ledger. In the technical sense, it is not, but it acts as one, because the collection of transactions on blocks is equivalent to a distributed ledger. However, you can build immutable distributed ledger applications based on the historical records that the blockchain provides. State Balances Bitcoin was not designed around accounts, although accounts are a more common way to think about the transactions that are taking place, because we are used to looking at our banking transactions as such.

With Satoshi’s abstract still in your mind, let us dive deeper with three different but complementary definitions of the blockchain: a technical, business, and legal one. Technically, the blockchain is a back-end database that maintains a distributed ledger that can be inspected openly. Business-wise, the blockchain is an exchange network for moving transactions, value, assets between peers, without the assistance of intermediaries. Legally speaking, the blockchain validates transactions, replacing previously trusted entities. TECHNICAL Back-end database that maintains a distributed ledger, openly. BUSINESS Exchange network for moving value between peers. LEGAL A transaction validation mechanism, not requiring intermediary assistance. Blockchain Capabilities = Technical + Business + Legal. THE WEB, ALL OVER AGAIN The past is not an accurate compass to the future, but understanding where we came from helps us gain an enlightened perspective and a better context for where we are going.

We could think of the traditional holders of central trust as today's guilds, and we could question why they should continue holding that trust, if technology (the blockchain) performed that function as well or even better. Blockchains liberate the trust function from outside existing boundaries, in the same way as medieval institutions were forced to cede control of printing. It is deceptive to view the blockchain primarily as a distributed ledger, because it represents only one of its many dimensions. It's like describing the Internet as a network only, or as just a publishing platform. These are necessary but not sufficient conditions or properties; blockchains are also greater than the sum of their parts. Blockchain proponents believe that trust should be free, and not in the hands of central forces that tax it, or control it in one form or another (e.g., fees, access rights, or permissions).


pages: 361 words: 97,787

The Curse of Cash by Kenneth S Rogoff

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Andrei Shleifer, Asian financial crisis, bank run, Ben Bernanke: helicopter money, Berlin Wall, bitcoin, blockchain, Bretton Woods, capital controls, Carmen Reinhart, cashless society, central bank independence, cryptocurrency, debt deflation, distributed ledger, Edward Snowden, ethereum blockchain, eurozone crisis, Fall of the Berlin Wall, fiat currency, financial intermediation, financial repression, forward guidance, frictionless, full employment, George Akerlof, German hyperinflation, illegal immigration, inflation targeting, informal economy, interest rate swap, Isaac Newton, Johann Wolfgang von Goethe, Kenneth Rogoff, labor-force participation, large denomination, liquidity trap, money: store of value / unit of account / medium of exchange, moral hazard, moveable type in China, New Economic Geography, offshore financial centre, oil shock, open economy, payday loans, price stability, purchasing power parity, quantitative easing, RAND corporation, RFID, savings glut, secular stagnation, seigniorage, The Great Moderation, the payments system, transaction costs, unbanked and underbanked, unconventional monetary instruments, underbanked, unorthodox policies, Y2K, yield curve

A simple but important point is that, ironically, the end objective of many cybertheft schemes often involves cash, typically withdrawn from an ATM.15 This is sometimes how criminals ultimately remove the funds they have transferred to bank accounts they control, possibly withdrawing currency via a network of people to avoid being conspicuous. Because the technology is evolving so rapidly, I am hesitant to go into much more detail, beyond saying that phasing out paper currency does not really move the needle much on society’s vulnerability to cybercrime. Some of the present-day obstacles to improving security are really more political than economic. Some innovations in security, such as the potentially disruptive distributed-ledger technology embodied in cryptocurrencies like Bitcoin or Ethereum, may eventually lead to major improvements in financial security, at least at the core of the payment system, as discussed further in chapter 14. It is particularly hard to see in any of these arguments why large-denomination notes are important. Probably they would be looked on askance after a power outage, earthquake, or other kind of catastrophe.

As things currently stand, the Federal Reserve does not directly weigh the welfare of other countries when determining its policy; they count only to the extent that any adverse effects might rebound back on the United States. This is hardly a desirable state of global governance but is not an issue I aim to tackle here. CHAPTER 14 Digital Currencies and Gold When I suggest to people that there might be benefits to phasing out paper currency, they almost invariably assume I am advocating a cryptocurrency like Bitcoin and are a bit disappointed to find out otherwise.1 No doubt anyone who looks at distributed-ledger technologies has to be excited about their potential applications in financial services and record keeping in general. For the foreseeable future, however, the best system is one in which a government-issued currency is the unit of account, though of course it will eventually morph into a fully electronic one. I appreciate that many leaders in the alternative payment space hold the libertarian view that new web-based transaction technologies can free people from the tyranny of government currency and regulation.

Plenty of other targets in the transaction ecosystem in theory could be overtaken by digital currencies, even after adjusting to regulation. The huge fees collected by credit card agencies, wire services, and other extant electronic transaction technologies make these media extremely vulnerable to disruptive innovators. Already, digital currencies are far cheaper for transmitting money internationally than wire services, where the charges can often run as much as 10–15% of the amount transmitted. And some applications of distributed-ledger technology offer the promise of cutting out intermediaries in transactions between, say, two banks. This would substantially reduce costs, particularly in international transactions. The approach can also be used to save on legal contracting costs. Some of Bitcoin’s competitors, notably the newer Ethereum platform, aim to offer the possibility of creating secure exchanges for transactions of almost any type.


pages: 296 words: 86,610

The Bitcoin Guidebook: How to Obtain, Invest, and Spend the World's First Decentralized Cryptocurrency by Ian Demartino

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3D printing, AltaVista, altcoin, bitcoin, blockchain, buy low sell high, capital controls, cloud computing, corporate governance, crowdsourcing, cryptocurrency, distributed ledger, Edward Snowden, Elon Musk, ethereum blockchain, fiat currency, Firefox, forensic accounting, global village, GnuPG, Google Earth, Haight Ashbury, Jacob Appelbaum, Kevin Kelly, Kickstarter, litecoin, M-Pesa, Marshall McLuhan, Oculus Rift, peer-to-peer lending, Ponzi scheme, prediction markets, ransomware, Satoshi Nakamoto, self-driving car, Skype, smart contracts, Steven Levy, the medium is the message, underbanked, WikiLeaks, Zimmermann PGP

Any person can digitally “hand” someone a bitcoin, multiple bitcoins, or a fraction of bitcoin, across the world or in the same room. Like handing someone cash, and unlike older digital financial systems, the money doesn’t have to go through an intermediary like a bank or another company. The advantages of using Bitcoin, which I will get to later, are what gives it its value. Bitcoin is also a distributed ledger, i.e., a record of every transaction and every Bitcoin wallet’s balance (you can think of a wallet as something akin to an account for now). This ledger is also called a blockchain. Every wallet, rather than being stored in a bank’s database, exists on this ledger; each wallet has its own private key and public key. The public key is also called the Bitcoin address. It is between 25 and 36 alphanumeric characters and begins with either a 1 or 3.

I won’t even make the argument that cash has been used for criminal activities far more often and for far longer than digital currencies, because the truth is that digital currencies are better suited for certain criminal activities than even cash is. Bitcoin is a useful tool and people will find uses for it, both good and bad. I suspect criminal activities surrounding digital currencies will only get more advanced in the future, but at the same time, so will legitimate investments and innovations. Bitcoin is many things. It is an online currency, a distributed ledger, and a decentralized network. And yet it may also become the fulfillment of the predictions, desires, and even fears of the early pioneers of the Internet. 1 “Statistics and Facts about Online Shopping.” Statista. June 2014. Accessed May 19, 2015. http://www.statista.com/topics/2477/online-shopping-behavior/. 2 Lewis, Peter H. “Attention Shoppers: Internet Is Open.” Editorial. The New York Times.

Some currencies failed because the company issuing them merely acted as money transactors themselves, adding an unnecessary middleman instead of eliminating one. Others failed because the issuer abused their power and scammed those who had bought in. Yet others ran afoul of government regulations.6 These issues are avoided with decentralization. When Satoshi Nakamoto invented the blockchain by combining the distributed ledger and proof-of-work concepts, he fulfilled the long-held vision of a workable, distributed, decentralized currency for the Internet. With it, anyone can transfer virtually any amount for a few cents or less. The blockchain tracks every transaction and its distributed nature ensures that no government agency can shut it down. The details of how this works will be covered in another chapter but the first use case of Bitcoin and the blockchain is the ability to transfer value on the Internet as easily as sending an email and almost as cheaply.


pages: 375 words: 88,306

The Sharing Economy: The End of Employment and the Rise of Crowd-Based Capitalism by Arun Sundararajan

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3D printing, additive manufacturing, Airbnb, Amazon Mechanical Turk, autonomous vehicles, barriers to entry, bitcoin, blockchain, Burning Man, call centre, collaborative consumption, collaborative economy, collective bargaining, corporate social responsibility, cryptocurrency, David Graeber, distributed ledger, employer provided health coverage, Erik Brynjolfsson, ethereum blockchain, Frank Levy and Richard Murnane: The New Division of Labor, future of work, George Akerlof, gig economy, housing crisis, Howard Rheingold, Internet of things, inventory management, invisible hand, job automation, job-hopping, Kickstarter, knowledge worker, Kula ring, Lyft, megacity, minimum wage unemployment, moral hazard, Network effects, new economy, Oculus Rift, pattern recognition, peer-to-peer lending, profit motive, purchasing power parity, race to the bottom, recommendation engine, regulatory arbitrage, rent control, Richard Florida, ride hailing / ride sharing, Robert Gordon, Ronald Coase, Second Machine Age, self-driving car, sharing economy, Silicon Valley, smart contracts, Snapchat, social software, supply-chain management, TaskRabbit, The Nature of the Firm, total factor productivity, transaction costs, transportation-network company, two-sided market, Uber and Lyft, Uber for X, universal basic income, Zipcar

Historically, protocols have emerged from either research projects or from individuals / small groups simply throwing something out that sticks. In the debate about bitcoin it is critical to understand that bitcoin has the potential to be such a protocol that enables a lot of new innovation to take place.9 Although the exact details of how Bitcoin works are a little more complicated than my short description in this section, a few key ideas come across: digital signatures that facilitate identity; the distributed ledger (the blockchain) that is stored on every client’s device; the crowd collectively clearing each transaction; the need to make clearing transactions challenging to avoid a potential takeover of the blockchain; and the need for an incentive (some equivalent of money, typically called the “coin” that is generated from within the system) to get the crowd interested in performing the challenging work that accompanies verifying transactions.

As the venture capitalist Chris Dixon wrote on his blog in 2014, Bitcoin makes activities like international microfinance, markets for computing capacity, incentivized social software, and other micropayments possible—not because we haven’t considered the value of these before, but because the transaction costs were too high.16 There are signs that traditional businesses will embrace many of the new capabilities of decentralized peer-to-peer technologies, much like Facebook actively uses BitTorrent within its privately owned server farms. In spring 2015, NASDAQ announced plans to leverage blockchain technology to support the development of a distributed ledger function for securities trading that will provide enhanced integrity, audit capabilities, governance, and transfer of ownership capabilities. The startup R3CEV has assembled a consortium of 25 of the world’s largest banks that are creating a framework for using blockchain technology in world financial markets.17 The startup Provenance provides a blockchain-based authentication service, where, for example, you can credibly establish the provenance of a high-value item by keeping track of and being able to access every trade associated with its ownership.


pages: 179 words: 43,441

The Fourth Industrial Revolution by Klaus Schwab

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3D printing, additive manufacturing, Airbnb, Amazon Mechanical Turk, Amazon Web Services, augmented reality, autonomous vehicles, barriers to entry, Baxter: Rethink Robotics, bitcoin, blockchain, Buckminster Fuller, call centre, clean water, collaborative consumption, conceptual framework, continuous integration, crowdsourcing, disintermediation, distributed ledger, Edward Snowden, Elon Musk, epigenetics, Erik Brynjolfsson, future of work, global value chain, Google Glasses, income inequality, Internet Archive, Internet of things, invention of the steam engine, job automation, job satisfaction, John Maynard Keynes: Economic Possibilities for our Grandchildren, John Maynard Keynes: technological unemployment, life extension, Lyft, megacity, meta analysis, meta-analysis, more computing power than Apollo, mutually assured destruction, Narrative Science, Network effects, Nicholas Carr, personalized medicine, precariat, precision agriculture, Productivity paradox, race to the bottom, randomized controlled trial, reshoring, RFID, rising living standards, Second Machine Age, secular stagnation, self-driving car, sharing economy, Silicon Valley, smart cities, smart contracts, software as a service, Stephen Hawking, Steve Jobs, Steven Levy, Stuxnet, The Spirit Level, total factor productivity, transaction costs, Uber and Lyft, Watson beat the top human players on Jeopardy!, WikiLeaks, winner-take-all economy, women in the workforce, working-age population, Y Combinator, Zipcar

For companies that are in the business of operating long and complex supply chains, this is transformative. In the near future, similar monitoring systems will also be applied to the movement and tracking of people. The digital revolution is creating radically new approaches that revolutionize the way in which individuals and institutions engage and collaborate. For example, the blockchain, often described as a “distributed ledger”, is a secure protocol where a network of computers collectively verifies a transaction before it can be recorded and approved. The technology that underpins the blockchain creates trust by enabling people who do not know each other (and thus have no underlying basis for trust) to collaborate without having to go through a neutral central authority – i.e. a custodian or central ledger. In essence, the blockchain is a shared, programmable, cryptographically secure and therefore trusted ledger which no single user controls and which can be inspected by everyone.


pages: 292 words: 85,151

Exponential Organizations: Why New Organizations Are Ten Times Better, Faster, and Cheaper Than Yours (And What to Do About It) by Salim Ismail, Yuri van Geest

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23andMe, 3D printing, Airbnb, Amazon Mechanical Turk, Amazon Web Services, augmented reality, autonomous vehicles, Baxter: Rethink Robotics, bioinformatics, bitcoin, Black Swan, blockchain, Burning Man, business intelligence, business process, call centre, chief data officer, Clayton Christensen, clean water, cloud computing, cognitive bias, collaborative consumption, collaborative economy, corporate social responsibility, cross-subsidies, crowdsourcing, cryptocurrency, dark matter, Dean Kamen, dematerialisation, discounted cash flows, distributed ledger, Edward Snowden, Elon Musk, en.wikipedia.org, ethereum blockchain, Galaxy Zoo, game design, Google Glasses, Google Hangouts, Google X / Alphabet X, gravity well, hiring and firing, Hyperloop, industrial robot, Innovator's Dilemma, Internet of things, Iridium satellite, Isaac Newton, Jeff Bezos, Kevin Kelly, Kickstarter, knowledge worker, Kodak vs Instagram, Law of Accelerating Returns, Lean Startup, life extension, loose coupling, loss aversion, Lyft, Mark Zuckerberg, market design, means of production, minimum viable product, natural language processing, Netflix Prize, Network effects, new economy, Oculus Rift, offshore financial centre, p-value, PageRank, pattern recognition, Paul Graham, Peter H. Diamandis: Planetary Resources, Peter Thiel, prediction markets, profit motive, publish or perish, Ray Kurzweil, recommendation engine, RFID, ride hailing / ride sharing, risk tolerance, Ronald Coase, Second Machine Age, self-driving car, sharing economy, Silicon Valley, skunkworks, Skype, smart contracts, Snapchat, social software, software is eating the world, speech recognition, stealth mode startup, Stephen Hawking, Steve Jobs, subscription business, supply-chain management, TaskRabbit, telepresence, telepresence robot, Tony Hsieh, transaction costs, Tyler Cowen: Great Stagnation, urban planning, WikiLeaks, winner-take-all economy, X Prize, Y Combinator

Implications: Algorithms driving more and more business decisions; AIs replacing a large percentage of knowledge workers; AIs looking for patterns in organizational data; algorithms embedded into products. Virtual/augmented reality Description: Avatar-quality VR available on desktop in 2-3 years. Oculus Rift, High Fidelity and Google Glass drive new applications. Implications: Remote viewing; centrally located experts serving more areas; new practice areas; remote medicine. Bitcoin and block chain Description: Trustless, ultra-low-cost secure transactions enabled by distributed ledgers that log everything. Implications: The blockchain becomes a trust engine; most third-party validation functions become automated (e.g., multi-signatory contracts, voting systems, audit practices). Micro-transactions and new payment systems become ubiquitous. Neuro-feedback Description: Use of feedback loops to bring the brain to a high level of precision. Implications: Capacity to test and deploy entirely new classes of applications (e.g., focus@will); group creativity apps; flow hacking; therapeutic aids, stress reduction and sleep improvement.


pages: 364 words: 99,897

The Industries of the Future by Alec Ross

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23andMe, 3D printing, Airbnb, algorithmic trading, AltaVista, Anne Wojcicki, autonomous vehicles, banking crisis, barriers to entry, Bernie Madoff, bioinformatics, bitcoin, blockchain, Brian Krebs, British Empire, business intelligence, call centre, carbon footprint, cloud computing, collaborative consumption, connected car, corporate governance, Credit Default Swap, cryptocurrency, David Brooks, disintermediation, Dissolution of the Soviet Union, distributed ledger, Edward Glaeser, Edward Snowden, en.wikipedia.org, Erik Brynjolfsson, fiat currency, future of work, global supply chain, Google X / Alphabet X, industrial robot, Internet of things, invention of the printing press, Jaron Lanier, Jeff Bezos, job automation, knowledge economy, knowledge worker, litecoin, M-Pesa, Mark Zuckerberg, Mikhail Gorbachev, mobile money, money: store of value / unit of account / medium of exchange, new economy, offshore financial centre, open economy, peer-to-peer lending, personalized medicine, Peter Thiel, precision agriculture, pre–internet, RAND corporation, Ray Kurzweil, recommendation engine, ride hailing / ride sharing, Satoshi Nakamoto, self-driving car, sharing economy, Silicon Valley, Silicon Valley startup, Skype, smart cities, social graph, software as a service, special economic zone, supply-chain management, supply-chain management software, technoutopianism, underbanked, Vernor Vinge, Watson beat the top human players on Jeopardy!, women in the workforce, Y Combinator, young professional

Fraud is further diminished by the fact that every bitcoin carries its history with it; to try to counterfeit a coin would require counterfeiting a false lineage going back all the way to the beginning of Bitcoin. It would never be accepted by the system, since the millions of copies of the ledger that reside throughout the rest of the Bitcoin network would not have any record of this counterfeit coin or its invented history. A widely distributed ledger lets everyone know who has what and prevents any individual from barging in with counterfeited property. The major headache that Satoshi Nakamoto conquered, and that every previous cryptocurrency had failed to manage, was the question of how to update that decentralized ledger: How could you make sure that the millions of copies of the master ledger, which are located far and wide throughout the Bitcoin network, are all the same, all accurate, all up to date, without anyone cheating?