Blockchains are classified according to the availability of a data ledger; this parameter divides the blockchain into classes. Although, the division into types is quite arbitrary because the technology itself is remaining the same. However, blockchain specialists have their own methods of classifying this system.
In summer 2015, Vitalik Buterin, creator of the Ethereum platform, published an article with three types of blockchain classification in the company’s blog:
Sir Mark Walport, chief science adviser of Great Britain, classified the blockchain in almost the same way. In his report about distributed ledgers and the blockchain potential in the field of public administration, he divided blockchain into these three types:
Often, to avoid confusion and to facilitate understanding, experts simply divide blockchains on open and closed ones. Russian blockchain experts adhere to this approach. Olga Skorobogatova, deputy chairman of the Central Bank of the Russian Federation, classifies blockchain exactly this way. She presented this topic at the ‘Blockchain and open platforms — 2016’ conference.
Despite different opinions in the professional environment, any blockchain division for types is based on the degree of blockchain openness for its participants. Therefore, to understand the specifics of the blockchain work, it is usually enough to know whether it is open or closed. In order to answer open is it or closed, we can simply answer several questions: