Chapter 2. Exploring Hyperledger Fabric

The focus of this chapter is the Hyperledger Fabric project—its components, design, reference architecture, and overall enterprise readiness. We will also discuss the broader aim of Linux Foundation (LF) hosted Hyperledger projects and the importance of open source and open standards. The goal is to build an understanding of the diversity of various Hyperledger projects, and what frameworks and tools may be suitable for particular enterprise use cases and software consumption models. While the blockchain technology landscape is constantly in flux, Hyperledger projects represent a structure that supports a mature and peer-reviewed technology geared toward enterprise consumption and fueled by a diverse set of talent and community interests.

This chapter will cover the following topics:

• The foundation of Hyperledger
• Hyperledger frameworks, tools, and building blocks
• Hyperledger Fabric component design
• Hyperledger Fabric – the journey of a sample transaction...

Building on the foundations of open computing

Open source projects, such as Linux and Java, have gained strength in mainstream businesses by serving as low-cost alternatives to commercial software. These capabilities rival those of proprietary software, thanks to support from a large developer community. Popular open source projects can also accelerate open standards, the collective building blocks for products, by serving as the common implementation. Businesses and vendors using open standards free up development and services budgets for items that offer higher value and competitive advantage.

Open source is a part of the wider open computing movement, along with open standards and open architecture. Together, these initiatives enable integration and flexibility, and benefit customers by helping them avoid vendor lock-in.

Enterprises are often required to adhere to various industry compliance and technology governance requirements, so it's important to consider the implications of open technology...

Hyperledger frameworks, tools, and building blocks

Now that we've looked at Hyperledger's foundations in the open computing movement, as well as its benefits for industry, let's talk about the frameworks, tools, and building blocks of Hyperledger.

Hyperledger frameworks

There are five blockchain frameworks, as follows:

• Hyperledger Iroha: Iroha, designed for mobile development projects, is based on Hyperledger Fabric and was contributed by Soramitsu, Hitachi, NTT Data, and Colu. It features modern, domain-driven C++ design as well as a new chain-based Byzantine fault tolerant consensus algorithm called Sumeragi.
• Hyperledger Sawtooth: Sawtooth was contributed by Intel and includes a novel consensus algorithm that Intel came up with that's called Proof of Elapsed Time (PoET). PoET aims to achieve distributed consensus as efficiently as possible. Hyperledger Sawtooth has potential in many areas, with support for both permissioned and permissionless deployments and recognition of diverse requirements...

Hyperledger Fabric component design

Let's discuss various components that facilitate the blockchain technology tenets of shared ledger, encryption, the trusts system, and smart contracts. The components represent the Hyperledger Fabric infrastructure components and provide isolation from chain code or smart contract development constructs. Chain code or smart contract development details will be discussed in detail in a separate chapter.

The following diagram depicts the Hyperledger Fabric infrastructure components: 

Hyperledger Fabric infrastructure components

Following are the infrastructure components:

• Hyperledger Fabric CA is an implementation of membership services but is not required to be used (that is, any X509-based PKI infrastructure that can issue EC certificates can be used)
• Dedicated orderer nodes
  • Implements atomic broadcast API
  • Orders and batches transactions and signs each batch (block) to create a hash chain
  • Hyperledger Fabric provides two implementations—Solo (for dev/test) and...

Hyperledger Fabric – the journey of a sample transaction

Now, let's look at the journey of a sample transaction with Hyperledger Fabric. This section will help lay the foundation of Hyperledger Fabric concepts and components in order to facilitate a better understanding of the layers involved in transaction processing:

Hyperledger Fabric walkthrough

Fabric introduces a newly designed blockchain, preserving the transaction processing architecture and aiming at a secure, scalable, resilient, modular, and confidential design. Hyperledger Fabric (at the time of writing this book, the current version is 1.1) supports the execution of distributed applications supporting enterprise-friendly programming models. The components in Hyperledger Fabric provide a modular design, optimally suited for a business network made of various enterprises. Hyperledger Fabric introduces a model based on three steps, an endorse-order-validate architecture, designed for the distributed execution of untrusted code in...

Hyperledger Fabric explored

Actors in the blockchain network: A blockchain is a network-based infrastructure where network-centric design, development, deployment, management, and support constructs apply. It is therefore vital to understand various actors and their roles that interact with the blockchain network for various purposes such as management, support, business users, regulator, and so on:

Each actor has a role and entry point and defines a governance structure that aids in network governance, audit, and compliance requirements. Business network governance (covered in detail in the following points) is an important compliance and costs consideration. Users are the parties who are users of the blockchain. They create and distribute blockchain applications and perform operations using the blockchain. These actors are consistent, and are based on cloud computing actors and roles from ISO/IEC 17788:

• Developers: Blockchain developers are the actors who create applications for users (client...

Understanding governance in business networks powered by blockchain

Governance can be defined as the centralized or decentralized body whose sole responsibility is establishing a set of rules or laws in a given system to make binding decisions. Governance in blockchain networks comes with a set of challenges and, in this section, we want to discuss those challenges along with governance structures in blockchain networks. Within the context of blockchain, the topic of governance presents an interesting paradox.

When a blockchain network is created, the governance structure is generally distributed, with input from the various stakeholders. Blockchain networks are characterized by decentralization and self-governance, with built-in control points and incentives to help maintain the right balance. Transactions go through a series of decentralized processing steps, with a decision that offers transaction finality as the output. This governance structure is based on incentive economics and consensus...

Summary

All of this helps you attract new participants to the network, as well as sustain the confidence of founding and existing participants, all while maintaining business benefits and value.

The business models and governance structures depend on each other to properly govern the operation of blockchain networks. A carefully planned governance model will ensure harmony between the involved entities, who may function as competitors, co-creators, or collaborators at different times.