Blockchain Technology Overview

A blockchain is a digital ledger made up of linked entries, referred to as blocks, that,
depending on the application, store some form of data. Cryptocurrencies, for instance, are
designed to record information regarding financial transactions. To decentralize the technology,
copies of a blockchain are shared and stored on all computers in a common network rather than
on a central server alone. No copy is considered more credible than another, and all changes
must be mutually verified, usually using a proof-of-work or proof-of-stake system. Collaboration
between computers to maintain the blockchain eliminates need for a centralized authority. By
design, this structure resists unauthorized modifications and allows for verification of
transactions between parties due to its immutable nature. Although these features hold for most
instances of blockchain, it is important to note that there are various implementations of the
technology, each having unique advantages and disadvantages. The issues discussed in the
sections of this report are in the context of the maritime sector, but are relevant to any agency
from the local, state, and federal level when considering blockchains for energy and
transportation issues (Winebrake et al., 2019).