An Overview of Blockchain Technology: Architecture and Consensus Protocols

Summary

A digital ledger, or blockchain, is one of today's most innovative and emerging technologies. Blockchain technology has evolved in the last decade to address the ambiguity and safety issues that come with using distributed networks. Due to its potential in business development for businesses and the increasingly emerging implementations of a distributed smart city system, government, and healthcare, the perception of blockchain has changed significantly over time. Many networks have been developed, each with its own architecture and consensus protocol. Primarily, everybody in the world thought Bitcoin was cryptocurrency, although there were also misconceptions of what the system was and how it might be used in company. Later, the impact of the Bitcoin central technology on industrialists and academicians in various realms such as banking, healthcare, and government has changed the perspective of researchers, industrialists, and academicians in various domains such as banking, healthcare, and government. A blockchain is made up of a series of transaction blocks that are linked together. Client/server (C/S) architecture is used in traditional C/S applications, which are managed by many administrators. However, blockchain is a distributed, open, and peer‐to‐peer network. Any network participant has the ability to monitor the network. All nodes work as an administrator to monitor and control the network. A blockchain network is made up of several nodes that are linked with each other, and the block, or data container, in the network cannot be modified without permission of the network.

The fundamental understanding of blockchain technology principles and keywords will be discussed in this chapter, so that a thorough understanding of the technology can be gain. The chapter is started from the brief introduction about the blockchain technology and then explained the blockchain architecture. In this architecture, we have explained how the blocks are linked with each other the how tempering of a block can be identified. As blockchain technology is a concept of chain of blocks, we have discussed the block structure. To understand the security in the blockchain, concept of hashing and digital signature is also discussed. The consensus protocol is at the heart of the blockchain, determining how it will work. Different types of consensus protocol, viz., Compute‐Intensive–Based Consensus (CIBC) Protocols, Capability‐Based Consensus Protocols, and Voting‐Based Consensus Protocols, with their respective sub types, are well explained in this chapter.