A blockchain has been defined as a distributed, decentralised ledger and peer-to-peer network which uses a defined, consensus mechanism to prevent modification of an ordered series of time-stamped records. From its initial introduction with Bitcoin in 2009, the potential of blockchain technology has continued to grow rapidly, and can be found in an increasing number of applications.
The most popular blockchain/distributed systems include:
Bitcoin
The introduction and implementation of Bitcoin – and all the digital currencies that have since followed it – was made possible by blockchain, which was the ground-breaking technology behind the whole cryptocurrency boom. Bitcoin focuses on one area of the blockchain technology, which is to run an electronic peer-to-peer electronic cash and payment system. Since 2009, the Bitcoin blockchain has operated without significant disruption, with any problems that have arisen being due to hacking or mismanagement, not with issues in the underlying system and code.
Ethereum
The second most popular cryptocurrency by market capitalisation, the Ethereum blockchain has much wider application than Bitcoin, in that is concerned not just with digital currency but with running the programming code of any decentralised application. Unlike most blockchains which limits the changes that developers can make, Ethereum allows them to create almost endless applications.
At the heart of the code is the “smart contract”, a legal agreement that a user and service provider, which acts like a computer program that is automatically executed when specific conditions are met, and which runs on the blockchain platform. Unlike Bitcoin, which is essentially passive, Ethereum is active with its own programming language, Solidity. The much wider possible applications of the Ethereum blockchain have got many major firms and governments interested in the technology.
Monax
Formerly known by the name Eris:db, Monax is an open-source platform which aims to extend the functionality of Bitcoin. Monax encourages developers to build, ship and run blockchain-based applications for business ecosystems. Deloittes, PWC and Accenture are among the firms who are running applications using Monax technology.
Chain Core
Chain Core is a blockchain platform which defines how assets are issued, transferred and controlled on a network. It uses a permissioned (meaning that the network is private and users have to apply to join) blockchain infrastructure), and can interface with existing core financial systems.
Openchain
This is an open source distributed ledger system for the issue and management of digital assets. It differs somewhat from traditional blockchain technology in that transactions are chained with one another, rather than grouped into blocks. Openchain provides instant confirmation of transactions, has no mining fees, and is highly scalable.
Hydrachain
Hydrachain is an Ethereum extension for creating permissioned distributed ledgers, aimed at the private client market, with the concept of the smart contract in mind. Its customers are typically those who are looking to the Ethereum blockchain to save costs, make business processes more effective, and create new innovative products.
Multichain
Multichain is an open-source blockchain platform for multi-asset financial transactions based on the Bitcoin blockchain. It is essentially a software tool for managing web assets and legal contracts, and is intended for banks and other financial institutions that previously have had concerns about the stability of the Bitcoin blockchain.