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- Herausgeber: Packt Publishing
- Kategorie: Wissenschaft und neue Technologien
- Sprache: Englisch
Understand how blockchain works and explore a variety of strategies to implement it in your organization effectively
Key Features
- Become familiar with business challenges faced by companies when using blockchain
- Discover how companies implement blockchain to monetize and secure their data
- Study real-world examples to understand blockchain and its use in organizations
Book Description
In addition to cryptocurrencies, blockchain-based apps are being developed in different industries such as banking, supply chain, and healthcare to achieve digital transformation and enhance user experience. Blockchain is not only about Bitcoin or cryptocurrencies, but also about different technologies such as peer-to-peer networks, consensus mechanisms, and cryptography. These technologies together help sustain trustless environments in which digital value can be transferred between individuals without intermediaries.
This book will help you understand the basics of blockchain such as consensus protocols, decentralized applications, and tokenization. You'll focus on how blockchain is used today in different industries and the technological challenges faced while implementing a blockchain strategy. The book also enables you, as a decision maker, to understand blockchain from a technical perspective and evaluate its applicability in your business. Finally, you'll get to grips with blockchain frameworks such as Hyperledger and Quorum and their usability.
By the end of this book, you'll have learned about the current use cases of blockchain and be able to implement a blockchain strategy on your own.
What you will learn
- Become well-versed with how blockchain works
- Understand the difference between blockchain and Bitcoin
- Learn how blockchain is being used in different industry verticals such as finance and retail
- Delve into the technological and organizational challenges of implementing blockchain
- Explore the possibilities that blockchain can unlock for decision makers
- Choose a blockchain framework best suited for your projects from options such as Ethereum and Hyperledger Fabric
Who this book is for
This book is for CXOs, business professionals, organization leaders, decision makers, technology enthusiasts, and managers who wish to understand how blockchain is implemented in different organizations, its impact, and how it can be customized according to business needs. Prior experience with blockchain is not required.
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Seitenzahl: 248
Veröffentlichungsjahr: 2019
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Blockchain for Decision Makers
Copyright © 2019 Packt Publishing
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Packt Publishing has endeavored to provide trademark information about all of the companies and products mentioned in this book by the appropriate use of capitals. However, Packt Publishing cannot guarantee the accuracy of this information.
Commissioning Editor: Sunith ShettyAcquisition Editor:Yogesh DeokarContent Development Editor:Athikho Sapuni RishanaSenior Editor: Sofi RogersTechnical Editor: Manikandan KurupCopy Editor: Safis EditingProject Coordinator:Kirti PisatProofreader: Safis EditingIndexer:Priyanka DhadkeProduction Designer:Aparna Bhagat
First published: September 2019
Production reference: 1260919
Published by Packt Publishing Ltd. Livery Place 35 Livery Street Birmingham B3 2PB, UK.
ISBN 978-1-83855-227-5
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Contributors
About the author
Romain Tormen is a senior consultant for PwC, a worldwide consulting firm. He has experience of digital transformation within a variety of industries and business units. Specializing in emerging technologies, he promotes the use of blockchain to his clients from the perspective of improved transaction security, transparency, disintermediation, and third-party authentication. He is a contributing writer to one of the most widely read, tech-oriented websites – hackernoon. Romain offers business insights and provides use cases for a broad range of industries.
About the reviewers
Narendranath Reddy is an experienced full stack blockchain engineer and Hyperledger Fabric expert with a proven track record of helping enterprises to build production-ready, blockchain-backed applications. He is an experienced innovator and creative thinker. He has won four hackathons on blockchain and is a keynote speaker, regularly speaking about blockchain and distributed ledgers. He is currently working as a blockchain software engineer at Consensys, Dubai, having previously worked as a blockchain developer at Blockgemini, Dubai, and as a software developer at UST Global, Trivandrum, and Madrid, Spain.
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Table of Contents
Title Page
Copyright and Credits
Blockchain for Decision Makers
About Packt
Why subscribe?
Contributors
About the author
About the reviewers
Packt is searching for authors like you
Preface
Who this book is for
What this book covers
To get the most out of this book
Download the color images
Conventions used
Get in touch
Reviews
Section 1: A First Step into Blockchain and an Exciting World
Basics of Blockchains and the Illustration of Village Beta
The significance of blockchain in the business world
Understanding blockchains
Using centralized ledger systems
The blockchain alternative
Empowering the ledger
The security factor
Processing the blockchain
Breaking down blockchains
The hash function
The missing variable
The incentives mechanism
The chain
Summary
A Technical Dive into Blockchain
No network, no blockchain
Truth in the network
Participants in the network
Cryptography
Understanding the data structure
Creating identities
Securing identities using blockchain
The Byzantine Generals Problem
Offering incentives
Understanding the consensus protocol mechanism
Summary
Ethereum and Smart Contracts
Which is better, Bitcoin or Ethereum?
The EVM
Understanding smart contracts
Gas
Comparing proof-of-work and proof-of-stake
Real-world applications
Summary
ICOs and Tokenized Fundraising Methods
What are ICOs?
Illustration of an ICO – the case of Ethereum
Utility tokens and security tokens
What is so revolutionary about ICOs?
Summary
Section 2: Blockchain in Practice, Insights, and Achievements
An Economic and Historical Approach of Blockchain
The economic global picture
Money is trust
A decentralized digital payment system
Bitcoin – a digital currency or gold 2.0?
Investment product or real solution for the unbanked?
Adverse governments
Technical limits of Bitcoin
Blockchain as the missing tool for a collaborative economy
Decentralization - but why?
Blockchain – the ultimate layer
Exchanging value in the digital world
Summary
Blockchain Legality, Compliance, and Regulation
Laying the groundwork
How to legally define a blockchain
Blockchain and GDPR
How to legally define tokens and other cryptoassets
Cryptocurrencies
Non-cryptocurrencies
Overview of regulation frameworks
Overview of accounting frameworks
Summary
Blockchain for the Business World and Achievements
Authentication and trustworthiness
Blockchain in the music industry
Leveraging the Internet of Things (IoT)
Interoperability
Traceability
Automation, disintermediation, and self-organization
Smart contracts for energy 
Electrical smarter grids
Smarter electric mobility
Betting with blockchains
Digital identities
How can blockchains help with citizenship?
Voting systems made easier with blockchains
Smart cities and public issues
Improving healthcare systems with blockchains
Can we achieve better administration with blockchains?
Managing land with blockchains
How blockchains support employment and education
Blockchains for waste management, charity, and others
Financial securities and fundraising
Digital uniqueness
Crypto-collectibles
Non-fungible token standards
Card collection
Tokenization of unique assets
Blockchain in the banking and finance sector
Summary
Future Outlook for Blockchain
Increasing investment in blockchain
Successful blockchain businesses
Blockchain and cryptocurrency investment trends 
The next GAFA
The future of cryptocurrencies 
Decentralized enterprise takeover
A plausible shift for governments
Threats and risks in the ecosystem
Summary
Section 3: Blockchain for Business Leaders
Infrastructures and Cloud-Based Solutions
The evolution of blockchains
Private, semi-private, and public blockchains
J.P. Morgan's Quorum
Hyperledger
Hyperledger Sawtooth
Hyperledger Fabric
Hyperledger Burrow, Indy, and Besu
Perspectives for Hyperledger
Aergo
Corda
Microsoft Azure
AWS
IBM
Oracle
Key takeaway
Summary
Defining Your Needs
Deciding to implement a blockchain
How much does a blockchain cost?
Challenges and issues
Business leaders' perception of blockchain
Blockchain in discussion
High profile opinions
Summary
Other Books You May Enjoy
Leave a review - let other readers know what you think
Preface
Blockchain-based apps, in addition to cryptocurrencies, are being developed in a variety of industries, including banking, the supply chain, and healthcare, in order to achieve digital transformation and enhance the user experience. Blockchain is not only about Bitcoin or cryptocurrencies, but also about different technologies, such as peer-to-peer networks, consensus mechanisms, and cryptography. These technologies together help to sustain trustless environments in which digital value can be transferred between individuals without intermediaries.
This book will help you understand the basics of blockchain, including cryptographic methods, hash functions, and consensus mechanisms. You will then focus on how blockchain is used today in different industries and the technological challenges faced while implementing a blockchain strategy. The book will also enable you, as a decision maker, to understand blockchain from a technical perspective and evaluate its applicability in business. Finally, you'll get to grips with cloud-based solutions and blockchain frameworks, such as Hyperledger and Quorum, and how to use them.
By the end of this book, you will have learned about the current use cases of blockchain and be able to implement a blockchain strategy on your own.
Who this book is for
This book is for CXOs, business professionals, organization leaders, decision makers, technology enthusiasts, and managers who wish to understand how blockchain is implemented in different organizations, its impact, and how it can be customized according to business needs. Prior experience with blockchain is not required.
What this book covers
Chapter 1, Basics of Blockchain and the Illustration of Village Beta, aims to provide the reader with a straightforward example in terms of understanding how blockchain truly works and how it can apply to real-life situations. It provides a brief introduction as to why blockchain is a genuine matter for C-level executives and gives an illustration of how it operates.
Chapter 2, A Technical Dive into Blockchain, includes a description of the components of blockchain, as well as a description of those stakeholders who compose a blockchain network, before describing a block and its data structure, the hash, the previous hash, the nonce, and the timestamp. We'll then describe hash functions and their role in blockchain as well as discover how cryptography plays an important role in managing identities in the network and identifying stakeholders to provide authentication. We'll introduce symmetric and asymmetric encryption methods and the underlying pairs of keys tied to each account (private and public). We'll explain consensus mechanisms and illustrate the Byzantine Generals Problem, which is the first computer science problem to raise questions regarding consensus in a network in the presence of traitors or faults. We'll eventually go through an explanation of how the network keeps working to achieve truth thanks to game theory and economics.
Chapter 3, Ethereum and Smart Contracts, introduces Ethereum, a decentralized platform running like an operating system to build decentralized applications. We'll describe the components of Ethereum, its Ethereum Virtual Machine, which acts as a computer program, its fuel, referred to as gas, and its smart contracts, which can trigger actions automatically in respect of their code. We'll explain why Ethereum is so successful, how it differs from Bitcoin, and focus on their underlying consensus mechanisms. We'll finally end the chapter by understanding Ethereum's roadmap to a more scalable and efficient infrastructure and discover a number of real-world applications built on Ethereum.
Chapter 4, ICOs and Tokenized Fundraising Methods, explain these new token-based fundraising methods, which generate new cryptocurrencies that are sold against other already existing liquid money. We'll understand the current success of ICOs and why they are so risky, both for investors and project leaders. We'll illustrate a number of ICOs, including Ethereum and the DAO, and differentiate between utility tokens from security tokens as well as introduce legal concerns from regulatory bodies.
Chapter 5, An Economic and Historical Approach of Blockchain,provides an economic approach to understanding both Bitcoin and blockchain. It gives historical insights and economic facts to place this new technology in a worldwide context.
Chapter 6, Blockchain Legality, Compliance, and Regulation, describes the regulations and the behavior of governments in relation to blockchain, ICOs and cryptocurrencies. While China was initially extremely cautious, the US attempted to legally define ICOs and provide a regulatory framework. Europe is adopting a wait-and-see approach, while there is a genuine need for entrepreneurs to be overseen and helped by public institutions.
Chapter 7, Blockchain for the Business World and Achievements, touches upon blockchain applications that have been developed in various industries and use cases that have been conceived. We'll cover several issues, including trustworthiness in official releases, interoperability between IT systems, traceability within supply chains, automation and disintermediation thanks to smart contracts, digital identity management, public and governmental challenges, tokenization in the financial industry, and finally, digital uniqueness. Many fields will be covered throughout this chapter, including retail, healthcare, automotive, luxury goods, manufacturing, shipping, finance, arts, music, and sports.
Chapter 8, Future Outlook for Blockchain, describes where blockchain is heading and what can be expected in the near future in terms of the global economy, as well as what enablers blockchain unlocks both for governments and decision makers.
Chapter 9, Infrastructures and Cloud-Based Solution, explains what kind of blockchain can be found on the market and how their functionalities have evolved over time. We'll introduce four main blockchain protocols that have been developed to advance enterprise-grade issues and infrastructures available for building a blockchain project. We'll also discover more accessible cloud-based solutions provided by web giants such as Amazon, Microsoft, and IBM.
Chapter 10,Defining Your Needs, provides you with a methodology to fulfill a blockchain strategy for your company by defining whether specific business needs could use blockchain as a tool. This chapter also raises important questions and an overview of the costs underlying a blockchain project. In this chapter, you will understand the boundaries in terms of the implementation of a blockchain and whether it is truly a necessity. As a decision maker, you should make pragmatic choices to achieve organic growth and embrace a mindset where becoming digital is only one step to becoming performant and profitable.
To get the most out of this book
This book is primarily intended for decision makers, C-level executives, and any business person willing to grasp the emerging and promising technology that blockchain is. The reader does not need to have specific technical skills or experience as a developer, but instead an ambition to possess the knowledge to understand the blockchain as a whole. What is needed is curiosity and open-mindedness in order to assimilate every piece of information displayed in this book. By the end of the ten chapters, you should be able to appreciate the wide and complex blockchain ecosystem, develop your own opinion, identify relevant use cases for your business, and lead it to success.
It is not mandatory to have an in-depth understanding of the technology before reading this book. However, a degree of familiarity with blockchain would be beneficial. In this regard, this book is beginner-friendly, but requires an important level of curiosity to explore further the different concepts enunciated.
Download the color images
We also provide a PDF file that has color images of the screenshots/diagrams used in this book. You can download it here: http://www.packtpub.com/sites/default/files/downloads/9781838552275_ColorImages.pdf.
Conventions used
Bold: Indicates a new term, an important word, or words that you see on screen. For example, words in menus or dialog boxes appear in the text like this. Here is an example: "Select System info from the Administration panel."
Get in touch
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Section 1: A First Step into Blockchain and an Exciting World
This section provides an explanation and illustration of blockchain, a description of the components of blockchain, and a true understanding of how it works.
This section comprises of the following chapters:
Chapter 1
,
Basics of Blockchain and the Illustration of Village Beta
Chapter 2
,
A Technical Dive into Blockchain
Chapter 3
,
Ethereum and Smart Contracts
Chapter 4
,
ICOs and Tokenized Fundraising Methods
Basics of Blockchains and the Illustration of Village Beta
Blockchain has been pushed into the limelight by a new and controversial form of digital currency called Bitcoin. The success stories of early Bitcoin investors and the launch of Ethereum, a platform allowing the creation of decentralized applications, brought blockchain and cryptocurrencies to the frontier where decision-makers and executives started to pay attention to this emerging piece of technology. Many curious persons began to wonder how it could help them in their personal or professional enterprises, leading them to believe that this innovation could be an appropriate answer to their business issues. The Economist, on October 31, 2015, published the first well-known article about blockchain (https://www.economist.com/printedition/covers/2015-10-29/ap-e-eu-la-me-na-uk).
As a decision-maker, being educated enough about new technologies and innovations is paramount for your company to explore and experiment with emerging enablers that will bring competitive advantages and help you to reach a steady growth. Being able to thrive in the digital age is more and more a necessity and a complex task, especially because technological breakthroughs and mass innovation trigger a sharp shift in people's consumption habits, as well as geopolitical challenges and economic changes. Being able to consider, evaluate, and incorporate new technologies to tackle your company's business goals has become critical.
With that in mind, you should be aware that blockchain has the potential to be a paradigm shift that can redesign how organizations operate and how value is shared between economic actors. This disruptive technology is said to change how the world works, how entire industries function, and how value is being exchanged and secured. But, as promising as it is, you must act with caution. We are at the dawn of what blockchain can achieve and it is not a hundred percent mature—it's still being considered an emerging technology.
Throughout this chapter, we will consider an illustration of a blockchain application that will help you to picture and grasp the concepts with ease. By the end of this chapter, you should be able to understand the usability of a blockchain in certain environments and conditions, especially when it comes to exchanging value directly between individuals. You should be able to explain basically how a blockchain works, what are its inner characteristics, and how Bitcoin operates without any central authority.
This chapter includes the following sections:
The significance of blockchain in the business world
Understanding blockchains
Breaking down blockchains
The significance of blockchain in the business world
The latest Gartner's Hype Cycle, published on August 20, 2018, shows how far blockchain is from massive adoption: 5 to 10 years (https://www.gartner.com/en/newsroom/press-releases/2018-08-20-gartner-identifies-five-emerging-technology-trends-that-will-blur-the-lines-between-human-and-machine).
As stated by Gartner, blockchain has shown many great stories and successful proof of concepts propelled by a wide media coverage and publicity, but still faces many failures and scalability issues. Some products have seen the light, with a real impact on economy and society (Bitcoin and Ethereum are the most well-known) but the mainstream adoption and broad market applicability (the so-called plateau of productivity) will be reached only if products are sustained with large investments and the technology is understood more and more.
According to PwC's 2018 Global Blockchain Survey, 84% of C-level executives report that their organization already has involvement with blockchain technology, but more than 65% of them have not pulled through the pilot stage yet.
There is a significant misunderstanding around the concept behind blockchain and its applicability within the business world. Cryptocurrencies and blockchain's recent hype makes executives assume that it stands as an answer to every business challenge. In fact, blockchain has to be considered as a layer for securitizing transactions and ensuring transparency of information and authentication of stakeholders in a decentralized environment. Blockchain is often seen as a difficult notion to grasp, especially for non-tech people. This book will help you to identify, as a decision-maker, the opportunities offered by blockchain for you to understand its applicability and ultimately give you the keys for initiating a blockchain project.
Understanding blockchains
Before diving instantly into the technical part, which will be covered in Chapter 2, A Technical Dive into Blockchain, you should first have an overview of what a blockchain is. If you have already read or heard about the topic, you might have figured out that it is appropriate for any use case relying on trust being ensured by a third party and where value is exchanged between different stakeholders. With the help of a simple example taken from an imaginary situation, the following sections will hopefully unravel the things you might have been confused about and the things you are eager to understand.
Using centralized ledger systems
Imagine a village of 20 people living on an island in the middle of the ocean, without connection to any other tribes or countries. We will call this village, Village Alpha. They live a peaceful life in a resourceful environment where no one lacks anything.
Question: How do the people of Village Alpha exchange and trade goods and services between each other?
Avoiding the downsides of bartering, they invent a gold-minted coin, a form of money similar to a dollar bill in today's economy. Because this coin is portable and easy to identify and has a value in the eyes of all of the villagers, it quickly becomes the principal means of payment within the community. To ensure proper trade between each other, they record every exchange in a ledger and appoint one of them as the referring bookkeeper to maintain its accuracy and authenticity. The appointed bookkeeper is rewarded for his/her integrity and honesty by collecting a fee on every transaction.
And that's it! People can buy and sell goods with their gold-minted coins. The truth is ensured by the bookkeeper who keeps the ledger up to date, incentivized to behave fairly by levying fees on transactions. Anyone can challenge him/her by checking the transactions to ascertain proper recording.
The villagers found a solution to their problem, unknowingly inventing the banking system that prevails nowadays.
Now, let's assume that the bookkeeper is dishonest. Imagine he/she modifies the ledger during the night and erases some transactions or adds new ones? What if he/she destroys the ledger?
You can see that this system has its shortcomings. The villagers are currently using what we call a centralized payment system where everyone relies on the bookkeeper to ensure the truth.
In our modern society, the bank plays the role of the bookkeeper. When you send money to a friend, you trust the bank to carry out the correct fund transfers
This has major downsides:
A single point of failure: Imagine a storm wipes out the village and the ledger with it.
A trusted third party that can be dishonest: Imagine the bookkeeper modifies the transactions.
A double-spending problem, which, however, is not applicable in our example because we assume they exchange physical goods. If the villagers were exchanging digital value, double-spending would have been an issue in the way that they would need an infrastructure to prevent replication of the digital assets. In other words, they would need a means to prevent an asset to be spent twice. More on that later.
The blockchain alternative
So, how does blockchain offer a powerful alternative to this traditional centralized payment system?
Let's take the village on the neighboring island to see how they proceeded from the initial problem of exchanging goods. This village, which we will call Village Beta, is also composed of 20 people.
Instead of electing one of them as the bookkeeper who will certify the truth and the history of transactions between them, they find another solution.
They create a book in which each page is designed as a spreadsheet with ten lines and three columns. The lines will be used to input transactions and the columns to input three pieces of information: the sender's address, the recipient's address, and the amount, as shown in the following diagram:
Then, they replicate the book 19 times and hand over one copy to each villager so that everyone possesses one book. Finally, they craft 10,000 coins that they call Villagecoin and distribute 10 to each one of them, leaving the remaining in a vault.
Empowering the ledger
When someone wants to make a transaction, he or she has to go to the central place of the village and shout to everybody else what transaction he or she is willing to make. When hearing the transaction, the other villagers write it down on the first page of their book: Alice gives 2 Villagecoin to Bob, Chuck gives 5 Villagecoin to Dan, and so on. In this way, every transaction is recorded in everyone's book, as shown in the following diagram:
With this system, no one was entrusted to assert the accuracy of a central book but instead, everyone is responsible for their own book.
This organization allows two things:
Transparency:
The villagers can check whether a villager has enough money. Since all of the transactions are recorded, it's easy to check that Alice cannot send 15 Villagecoin to Dan, since she was given 10 Villagecoin on the first day and then sent 2 Villagecoin to Bob. She has therefore, only 8 Villagecoin remaining.
A first level of security:
Since everyone should have the same book and history of transactions, if Alice came to falsify a transaction in her book, it would turn invalid because everyone else (the majority) has the correct transactions recorded. Alice would just end up with an incorrect book and would need to retrieve a valid copy from another villager.
In this example, the book is what we call a database (or ledger), where all transactions and value transfers are logged. The village is the community that empowers the ledger; it is a network infrastructure where the villagers are the following:
The nodes and the miners
: They are the entities that validate the transactions and store the ledger (more on that later).
They are
the users of the service
provided by the network. In this example, the service is the ability to use a decentralized means of payment (Villagecoin) to sell and purchase physical goods. It can be compared to Bitcoin.
So far, we have seen some quite interesting things. We already demonstrated the decentralization feature of the blockchain and how a database can be shared and track-recorded across a network without being altered.
Now comes the most important and hardest feature to understand: security.
The security factor
As stated before, each page of the book is designed with 10 lines. So, what happens when we get to transaction number #10
