IEEE Systems, Man and Cybernetics Magazine - October 2022 - 7

[3], to ensure data immutability. We demonstrate that to create
an insurmountable barrier against attacks on data
immutability, decentralization and system scale are both
essential. Based on this discussion, we argue that private
and consortium blockchain are centralized systems and violate
the design principle of blockchain technology. Thus,
they should be clearly differentiated from blockchain technology
as we know it, and particularly, data immutability is
not guaranteed at all in private and consortium blockchain.
Before we conclude, we outline challenges and developments
in blockchain research.
More specifically, this article makes the following
contributions:
◆ First, this article aims to define blockchain technology
in an authoritative way by emphasizing its design principle
and innovations. Blockchain technology is based
on decentralization and needs network scale to achieve
its purpose. It provides the first practical solution for
reaching consensus in a large decentralized system.
◆ Second, this article describes the benefits of blockchain
technology in a systematic manner. These benefits
are largely determined by the design principle and
innovations in blockchain, where decentralization
plays an essential role.
◆ Third, we provide an in-depth discussion of how data
immutability is achievable in blockchain technology.
Being a decentralized, trustless system, the only way
of achieving data immutability is to enact an insurmountable
barrier to changing information on the
blockchain. To accomplish this, blockchain technology
introduced a set of clever mechanisms consisting of
cryptography, the chaining of blocks, and decentralized
consensus based on proof of work (PoW). However,
the system must grow to be very large for the
barrier to be high. To facilitate that growth, blockchain
technology has a built-in incentive; i.e., it offers a block
reward for the miner who successfully solves the puzzle
at each block height. This mechanism attracts people
to invest in and join the system.
◆ Finally, we dissect the value of private and consortium
blockchain. We point out that the biggest difference
between private/consortium blockchain and public
blockchain is that the former is a centrally controlled
system. The lack of decentralization removes many of
the benefits of public blockchain, especially data
immutability, because the owner of a system could
arbitrarily change information.
Related Work
Due to the sheer number of review articles and books on
blockchain, it is not practical to compare each of them. In
Table 1, we highlight a subset of related works [2], [4]-[10]
in comparison with this article. The comparison covers a
number of categories, including whether or not and to what
extent a publication elaborated on 1) the building blocks of
blockchain technology, 2) the benefits of blockchain technology,
3) the applications of blockchain, 4) the challenges
for future development in blockchain, 5) how data
October 2022 IEEE SYSTEMS, MAN, & CYBERNETICS MAGAZINE
7
IMAGE LICENSED BY INGRAM PUBLISHING
IEEE Systems, Man and Cybernetics Magazine - October 2022

Table of Contents for the Digital Edition of IEEE Systems, Man and Cybernetics Magazine - October 2022
