ABSTRACT
Blockchain refers to a distributed, encrypted database, which is a public depository of information that cannot be reversed and is incorruptible. In other words, a blockchain can be defined as a distributed public ledger or database of records of every transaction that has been carried out and shared among those participating in the network. Every transaction or digital event in the public ledger has to be authenticated via the agreement of more than half of those participating in the network. This implies that no participant or user as an individual can modify any data within a blockchain without the consent of other users (participants). Blockchain is an immutable distributed ledger that can be used to record everything of value. Blockchain until now has been associated with financial transactions, but eventually, blockchain can be used to record and manage anything that has value. Blockchain technology delivers unbelievable traceability that is autonomous and trusted by creating permanent records of data and transactions. It thereby brings the single source of truth and no single point of failure to all stakeholders, as everything related to data and transactions are always visible on the network. Blockchain replaces the need to trust accredited third parties with the trust of the system as a whole. After introducing peer-to-peer networks, the chapter introduces blockchain concept, architecture, benefits and operations. It then discusses aspects of blockchain that highlighted its potential for provisioning of security. In the last part of the chapter, it explains blockchain enabled security solution and architecture for Internet of Things (IoT) systems.
