ABSTRACT
The blockchain technology, proposed by Satoshi Nakamoto, is a digital distribution system that is mainly anticipated for financial transactions such as bitcoin and later used the delivery of a distributed database that depends on a peer-to-peer (P2P) grid system with a high level of confidence, availability, and integrity (CIA) deprived of requiring the help of a trusted third party (TTP).
The blockchain system encompasses numerous distributed linked blocks controlled by the use of DLT technology (distributed ledger technology). Every block in the chain retains a number of transactions, and when a new transaction takes place, a new block is attached to the end of the chain.
This decentralized environment and structural design of blockchain systems make blockchain’s robustness, immutability, and anonymity. Thus it is a secure technology that is difficult to attack or cheat. Consequently, blockchain has gained admissibility to use diverse fields such as governments, industry, cryptocurrency, healthcare, and Internet of Things (IoT) technology.
A short review of blockchain technology will invite this chapter to familiarize the reader with the main concepts of blockchain systems such as blocks, chains, the decentralized architecture of blockchain technology, and the different features that correlate the blockchain system with the diverse security applications such as smart contract platform, consensus mechanism and mining, and the distributed ledger.
After that, we will consider reviewing some of the research studies that use blockchain to provide security solutions in different areas, including governments, industry, cryptocurrency, healthcare, and IoT. After that, we will traverse through the security of blockchain policies, features, and algorithms.
Moreover, we will develop a systematic brief for security issues and exploitations of blockchain technology such as 51% vulnerability risk, double spending, exploring Sybil, and others.
