ABSTRACT
Blockchain technology is the next big thing in the applied science. It is a cryptography-based distributed digital ledger with a chain of information blocks identified using cryptographic signature. In general, a blockchain is a new version of database that allows many participants to concurrently share the database with a provision to alter it in a securable manner. Blockchain facilitates the most reliable transaction among unreliable contributors in the network, and hence, has raised noteworthy attention among scientists, developers and research scholars. The blocks of non-editable information are back linked, and to access a particular block, it is mandatory to refer to the previous block signature, which can be traced all the way back to the very first block created. The designing pattern of blockchain requires a solid cryptography, which includes a prior hashing to validate the existing transaction as well as the cumulative transaction along with consensus algorithm for contributor to consent a particular transaction to the global tamper-resistant ledger. If an invader makes an attempt to alter a block, they have to alter all blocks that are included afterwards the most recent block, which makes the attack impossible. The components of blockchain are cryptography, peer-to-peer network, consensus mechanism, ledger and a set of protocols. Based on the application, the blockchain is considered as public and private. In public, the details of the contributors are not known and the transaction is carried out with the help of mathematical proof. In contrast to this, in private blockchain, the contributors know the identity of each other and trust mutually by definition. The Bank of Japan and the European Central Bank have conducted a joint research project on blockchain, called Stella, in the year 2007 in the financial market infrastructure and announced that the blockchain technology is the ideal solution that satisfies the performance needs in a real-time gross settlement system. It is estimated that the global cost of financial fraud is 20 billion USD annually. Blockchain technology identifies the fraud immediately in the network with the help of real-time audit trail. With its security characteristics, blockchain is influencing the global currency market by evading Denial Of Service and Ransomware while holding historic immutability, which attracts the industries not restricted to logistics, pharmaceuticals, banking, cyber security and smart contracts with incomparable performance. The United States Defence Advanced Research Projects Agency (DARPA) requested to enforce blockchain technology to develop a ‘Secure Messaging Platform’ to exchange messages through a decentralized protocol. This proves the efficiency of blockchain-based system. In this chapter, the performance of blockchain-based system is discussed and evaluated for various applications.
