Book Image

Blockchain Quick Start Guide

By : Xun (Brian) Wu, Weimin Sun
Book Image

Blockchain Quick Start Guide

By: Xun (Brian) Wu, Weimin Sun

Overview of this book

Blockchain is a technology that powers the development of decentralized applications.This technology allows the construction of a network with no single control that enables participants to make contributions to and receive benefits from the network directly. This book will give you a thorough overview of blockchain and explain how a blockchain works.You will begin by going through various blockchain consensus mechanisms and cryptographic hash functions. You will then learn the fundamentals of programming in Solidity – the defacto language for developing decentralize, applications in Ethereum. After that, you will set up an Ethereum development environment and develop, package, build, and test campaign-decentralized applications.The book also shows you how to set up Hyperledger composer tools, analyze business scenarios, design business models, and write a chain code. Finally, you will get a glimpse of how blockchain is actually used in different real-world domains. By the end of this guide, you will be comfortable working with basic blockchain frameworks, and develop secure, decentralized applications in a hassle-free manner.
Table of Contents (14 chapters)
Title Page
Copyright and Credits
About Packt

Key concepts in Hyperledger Fabric

If you want to use Hyperledger Fabric effectively, you have to understand its key concepts. This includes ledger, chaincode, and channel.


The ledger is the sequenced, immutable, entire historical record of all state transactions. All the transactions that are performed will be added to the ledger. We can find the entire transaction history for each channel. A fabric blockchain ledger has two types of data—a world state and a blockchain transaction ledger. The world state, which is stored stored in a database, LevelDB, is the default database. The state data is mutable. It has a version number that keeps incrementally updated when the state changes. On the other hand, the ledger data is immutable, and is stored as a file. It records transaction data block information, which contains a sequence of transactions. Each block's header includes a hash of the block's transactions, as shown in the following diagram:


Chaincode is a program (or programs...