@ -24,7 +24,7 @@ In this chapter, you will learn how to set up each of the software packages for
=== Lightning development environment
((("development environment", "setup")))If you're a developer, you will want to set up a development environment with all the tools, libraries, and support software for writing and running Lightning software. In this highly technical chapter, we'll walk through that process step-by-step. If the material becomes too dense or you're not actually setting up a development environment, then feel free to skip to the next chapter, which is less technical.
If you're a developer, you will want to set up a development environment with all the tools, libraries, and support software for writing and running Lightning software. In this highly technical chapter, we'll walk through that process step-by-step. If the material becomes too dense or you're not actually setting up a development environment, then feel free to skip to the next chapter, which is less technical.
==== Using the command-line
@ -34,7 +34,7 @@ In most of the examples here, we will be building the software directly from the
[TIP]
====
((("$ symbol")))((("shell commands")))((("terminal applications")))In many of the examples in this chapter we will be using the operating system's command-line interface (also known as a "shell"), accessed via a "terminal" application. The shell will first display a prompt as an indicator that it is ready for your command. Then you type a command and press "Enter" to which the shell responds with some text and a new prompt for your next command. The prompt may look different on your system, but in the following examples it is denoted by a +$+ symbol. In the examples, when you see text after a +$+ symbol, don't type the +$+ symbol but type the command immediately following it. Then press the Enter key to execute the command. In the examples, the lines below each command are the operating system's responses to that command. When you see the next +$+ prefix, you'll know it is a new command and you should repeat the process.
In many of the examples in this chapter we will be using the operating system's command-line interface (also known as a "shell"), accessed via a "terminal" application. The shell will first display a prompt as an indicator that it is ready for your command. Then you type a command and press "Enter" to which the shell responds with some text and a new prompt for your next command. The prompt may look different on your system, but in the following examples it is denoted by a +$+ symbol. In the examples, when you see text after a +$+ symbol, don't type the +$+ symbol but type the command immediately following it. Then press the Enter key to execute the command. In the examples, the lines below each command are the operating system's responses to that command. When you see the next +$+ prefix, you'll know it is a new command and you should repeat the process.
====
To keep things consistent, we use the +bash+ shell in all command-line examples. While other shells will behave in a similar way, and you will be able to run all the examples without it, some of the shell scripts are written specifically for the +bash+ shell and may require some changes or customizations to run in another shell. For consistency, you can install the +bash+ shell on Windows and Mac OS, and it comes installed by default on most Linux systems.
@ -239,7 +239,7 @@ If she does not provide the secret by this time, Chan's deposit will be refunded
With such a chain of contracts we can ensure that, after 24 hours, the payment will successfully go from Alice to Bob to Chan to Dina, or it will fail and everyone will be refunded.
Either the contract fails or succeeds, there's no middle ground.
In the context of the Lightning Network, we call this "all or nothing" property ((("atomicity")))_atomicity_.
In the context of the Lightning Network, we call this "all or nothing" property _atomicity_.
As long as the escrow is trustworthy and faithfully performs its duty, then no party will have their coins stolen in the process.
@ -337,7 +337,7 @@ H = SHA256(R)
In <<payment_hash_and_preimage>> +H+ is the hash, or _payment hash_ and +R+ is the secret or _payment pre-image_.
The use of a cryptographic hash function is one element that guarantees ((("trustless")))_trustless operation_. The payment intermediaries do not need to trust each other because they know that no one can guess the secret or fake it.
The use of a cryptographic hash function is one element that guarantees _trustless operation_. The payment intermediaries do not need to trust each other because they know that no one can guess the secret or fake it.
@ -23,15 +23,15 @@ This chapter covers several important concepts from Bitcoin, including:
=== Keys and digital signatures
((("cryptography", "defined")))((("cryptography", see="also keys and addresses")))You may have heard that bitcoin is based on _cryptography_, which is a branch of mathematics used extensively in computer security. Cryptography can also be used to prove knowledge of a secret without revealing that secret (digital signature), or prove the authenticity of data (digital fingerprint). These types of cryptographic proofs are the mathematical tools critical to bitcoin and used extensively in bitcoin applications.
You may have heard that bitcoin is based on _cryptography_, which is a branch of mathematics used extensively in computer security. Cryptography can also be used to prove knowledge of a secret without revealing that secret (digital signature), or prove the authenticity of data (digital fingerprint). These types of cryptographic proofs are the mathematical tools critical to bitcoin and used extensively in bitcoin applications.
((("digital keys", see="keys and addresses")))((("keys and addresses", "overview of")))((("digital signatures", "purpose of")))Ownership of bitcoin is established through _digital keys_, _bitcoin addresses_, and _digital signatures_. The digital keys are not actually stored in the network, but are instead created and stored by users in a file, or simple database, called a _wallet_. The digital keys in a user's wallet are completely independent of the bitcoin protocol and can be generated and managed by the user's wallet software without reference to the blockchain or access to the internet.
Ownership of bitcoin is established through _digital keys_, _bitcoin addresses_, and _digital signatures_. The digital keys are not actually stored in the network, but are instead created and stored by users in a file, or simple database, called a _wallet_. The digital keys in a user's wallet are completely independent of the bitcoin protocol and can be generated and managed by the user's wallet software without reference to the blockchain or access to the internet.
Most bitcoin transactions require a valid digital signature to be included in the blockchain, which can only be generated with a secret key; therefore, anyone with a copy of that key has control of the bitcoin. ((("witnesses")))The digital signature used to spend funds is also referred to as a _witness_, a term used in cryptography. The witness data in a bitcoin transaction testifies to the true ownership of the funds being spent. ((("public and private keys", "key pairs")))((("public and private keys", see="also keys and addresses")))Keys come in pairs consisting of a private (secret) key and a public key. Think of the public key as similar to a bank account number and the private key as similar to the secret PIN.
Most bitcoin transactions require a valid digital signature to be included in the blockchain, which can only be generated with a secret key; therefore, anyone with a copy of that key has control of the bitcoin. The digital signature used to spend funds is also referred to as a _witness_, a term used in cryptography. The witness data in a bitcoin transaction testifies to the true ownership of the funds being spent. Keys come in pairs consisting of a private (secret) key and a public key. Think of the public key as similar to a bank account number and the private key as similar to the secret PIN.
==== Private and public keys
((("keys and addresses", "overview of", "private key generation")))((("warnings and cautions", "private key protection")))A private key is simply a number, picked at random. In practice, and to make managing many keys easy, most bitcoin wallets generate a sequence of private keys from a single random _seed_, using a deterministic derivation algorithm. Simply put, a single random number is used to produce a repeatable sequence of seemingly random numbers that are used as private keys. This allows users to only backup the seed and be able to _derive_ all the keys they need from that seed.
A private key is simply a number, picked at random. In practice, and to make managing many keys easy, most bitcoin wallets generate a sequence of private keys from a single random _seed_, using a deterministic derivation algorithm. Simply put, a single random number is used to produce a repeatable sequence of seemingly random numbers that are used as private keys. This allows users to only backup the seed and be able to _derive_ all the keys they need from that seed.
Bitcoin, like many other cryptocurrencies and blockchains, uses _elliptic curves_ for security. In Bitcoin, elliptic curve multiplication on the _secp256k1_ elliptic curve is used as a _one-way function_. Simply put, the nature of elliptic curve math makes it trivial to calculate the scalar multiplication of a point but impossible to calculate the inverse ("division", or "discrete logarithm").
@ -446,7 +446,7 @@ When reading Bitcoin Script, remember that the condition being evaluated comes _
A very common use for flow control in Bitcoin Script is to construct a locking script that offers multiple execution paths, each a different way of redeeming the UTXO.
((("use cases", "buying coffee")))Let's look at a simple example, where we have two signers, Alice and Bob, and either one is able to redeem. With multisig, this would be expressed as a 1-of-2 multisig script. For the sake of demonstration, we will do the same thing with an +IF+ clause:
Let's look at a simple example, where we have two signers, Alice and Bob, and either one is able to redeem. With multisig, this would be expressed as a 1-of-2 multisig script. For the sake of demonstration, we will do the same thing with an +IF+ clause:
Also, the topology is important for features such as the autopilot.
satoshi::
A satoshi is the smallest denomination of bitcoin that can be recorded on the blockchain. It is the equivalent of 0.00000001 bitcoin and is named after the creator of Bitcoin, Satoshi Nakamoto. ((("satoshi")))
A satoshi is the smallest denomination of bitcoin that can be recorded on the blockchain. It is the equivalent of 0.00000001 bitcoin and is named after the creator of Bitcoin, Satoshi Nakamoto.
Satoshi Nakamoto::
Satoshi Nakamoto is the name used by the person or group of people who designed Bitcoin and created its original reference implementation, Bitcoin Core. As a part of the implementation, they also devised the first blockchain database. In the process, they were the first to solve the double-spending problem for digital currency. Their real identity remains unknown.
@ -9,12 +9,12 @@ This book is a collaboration between Andreas M. Antonopoulos, Olaoluwa Osuntokun
[[intended_audience_sec]]
=== Intended Audience
((("intended audience")))This book is mostly intended for technical readers with an understanding of the fundamentals of Bitcoin and other open blockchains.
This book is mostly intended for technical readers with an understanding of the fundamentals of Bitcoin and other open blockchains.
[[conventinons_used_sec]]
=== Conventions Used in This Book
((("typographical conventions")))The following typographical conventions are used in this book:
The following typographical conventions are used in this book:
_Italic_:: Indicates new terms, URLs, email addresses, filenames, and file extensions.
@ -42,7 +42,7 @@ This element indicates a warning or caution.
[[code_examples_sec]]
=== Code Examples
((("code examples, obtaining and using")))The examples are illustrated in Go, C++, Python, and using the command line of a Unix-like operating system. All code snippets are available in the GitHub repository under the _code_ subdirectory. Fork the book code, try the code examples, or submit corrections via GitHub: https://github.com/lnbook/lnbook.
The examples are illustrated in Go, C++, Python, and using the command line of a Unix-like operating system. All code snippets are available in the GitHub repository under the _code_ subdirectory. Fork the book code, try the code examples, or submit corrections via GitHub: https://github.com/lnbook/lnbook.
All the code snippets can be replicated on most operating systems with a minimal installation of compilers, interpreters, and libraries for the corresponding languages. Where necessary, we provide basic installation instructions and step-by-step examples of the output of those instructions.
@ -55,9 +55,9 @@ All the code snippets use real values and calculations where possible, so that y
This book is here to help you get your job done. In general, if example code is offered with this book, you may use it in your programs and documentation. You do not need to contact us for permission unless you're reproducing a significant portion of the code. For example, writing a program that uses several chunks of code from this book does not require permission. Selling or distributing a CD-ROM of examples from O'Reilly books does require permission. Answering a question by citing this book and quoting example code does not require permission. Incorporating a significant amount of example code from this book into your product's documentation does require permission.
((("attribution")))We appreciate, but do not require, attribution. An attribution usually includes the title, author, publisher, ISBN, and copyright. For example: “__Mastering the Lightning Network__ by Andreas M. Antonopoulos, Olaoluwa Osuntokun, Rene Pickhardt (O'Reilly). Copyright 2020, ISBN - xxx-xx-x-xxxxx."
We appreciate, but do not require, attribution. An attribution usually includes the title, author, publisher, ISBN, and copyright. For example: “__Mastering the Lightning Network__ by Andreas M. Antonopoulos, Olaoluwa Osuntokun, Rene Pickhardt (O'Reilly). Copyright 2020, ISBN - xxx-xx-x-xxxxx."
((("open source licenses")))__Mastering the Lightning Network__ is offered under the Creative Commons Attribution-Noncommercial-No Derivative Works 4.0 International License (CC BY-NC-ND 4.0).
__Mastering the Lightning Network__ is offered under the Creative Commons Attribution-Noncommercial-No Derivative Works 4.0 International License (CC BY-NC-ND 4.0).
If you feel your use of code examples falls outside fair use or the permission given above, feel free to contact us at pass:[<a href="mailto:permissions@oreilly.com">permissions@oreilly.com</a>].
@ -68,9 +68,9 @@ All references to companies and products are intended for educational, demonstra
[[addresses_and_transactions_sec]]
=== Addresses and Transactions in this Book
((("blockchain","warnings and cautions")))((("keys and addresses", seealso="cryptography; private keys; public keys")))((("QR codes")))((("transactions","warnings and cautions")))((("warnings and cautions","when using test and example material appearing in book")))The Bitcoin addresses, transactions, keys, QR codes, and blockchain data used in this book are, for the most part, real. That means you can browse the blockchain, look at the transactions offered as examples, retrieve them with your own scripts or programs, etc.
The Bitcoin addresses, transactions, keys, QR codes, and blockchain data used in this book are, for the most part, real. That means you can browse the blockchain, look at the transactions offered as examples, retrieve them with your own scripts or programs, etc.
((("warnings and cautions","avoid sending money to addresses appearing in book")))However, note that the private keys used to construct the addresses printed in this book have been "burned." This means that if you send money to any of these addresses, the money will either be lost forever or (more likely) appropriated, since anyone who reads the book can take it using the private keys printed herein.
However, note that the private keys used to construct the addresses printed in this book have been "burned." This means that if you send money to any of these addresses, the money will either be lost forever or (more likely) appropriated, since anyone who reads the book can take it using the private keys printed herein.
[WARNING]
====
@ -92,7 +92,7 @@ Our unique network of experts and innovators share their knowledge and expertise
Information about _Mastering the Lightning Network_ as well as the Open Edition and translations are available at link:$$https://lnbook.info/$$[].
((("comments and questions")))((("contact information")))Please address comments and questions concerning this book to the publisher:
Please address comments and questions concerning this book to the publisher:
Nick Adams
3 years ago