Dylan J. Yaga, Peter M. Mell, Nik Roby, Karen Scarfone
Blockchains are tamper evident and tamper resistant digital ledgers implemented in a distributed fashion (i.e., without a central repository) and usually without a central authority (i.e., a bank, company, or government). At their basic level, they enable a community of users to record transactions in a shared ledger within that community, such that under normal operation of the blockchain network no transaction can be changed once published. This document provides a high-level technical overview of blockchain technology. It discusses its application to cryptocurrency in depth, but also shows its broader applications. The purpose is to help readers understand how blockchain technology works, so that they can be applied to technology problems.
blockchain, consensus model, cryptocurrency, cryptographic hash function, asymmetric-key cryptography, distributed ledger, distributed consensus algorithm, proof of work, proof of stake, round robin, proof of authority, proof of identity, proof of elapsed time, soft fork, hard fork, smart contracts, data oracle