What is a blockchain?

From the technical point of view, a blockchain implies technology of implementation a concept distributed and cryptography the protected registers on the basis of peer-to-peer (P2P, peer-to-peer) networks.

Such registers are characterized by properties of append-only update of new records (blocks), invariability of data (extremely improbable possibility of change) and also can be updated only in case of reaching consensus or consent between participants of a network.

Blockchain system are developed on the basis of a combination of the following principal technological components: peer-to-peer networks (technologies of implementation of networks of equivalent nodes which can interact among themselves without involvement of uniform central plenipotentiary nodes owing to what the received networks have no uniform point of a failure), asymmetric cryptography (a method of encoding thanks to which nodes of a network can exchange the ciphered messages among themselves in such a way that any user has an opportunity to verify authenticity of the sender but only the alleged receiver will be able to get access to message contents), cryptography hashing (the method of creation of compact and unique “prints” (hash amounts) of any data allowing to make fast comparison of big data sets and providing the reliable mechanism of check of the invariance of data), reaching consensus algorithms (mechanisms of achievement of coordination between network nodes).

From a point of sight of users the blockchain can be considered as the multifunction and multilayer system or the platform intended for accounting of different assets in a digital form and also for implementation of operations between participants without involvement of the central entrusted intermediary.

It is considered that the fundamental principles of functioning blockchain systems were underlain thanks to researchers and experiments with digital currencies of the expert in cryptography Adam Beck, developed into appearance in 2002 of the algorithm Hashcash assuming use of the mechanism of a mining for implementation and transaction processing. To this innovative development, the algorithm of achievement of the distributed consensus was added to implementations of the first cryptocurrency of Bitcoin which appeared in 2009, her pseudo-anonymous creator Satosi Nakamoto. Creation of Bitcoin marked itself appearance of the first generation of blockchains (a blockchain 1.0) to which carry both bitcoin, and alternative cryptocurrencies and also applications for operation with them. The development used by different financial services or the companies, consisting in the implementation of a functionality of interaction with different financial assets belonging to the second generation of blockchains (a blockchain 2.0). And in the category of the third generation of blockchains (a blockchain 3.0) select a blockchain technology which application goes beyond narrowly targeted branch of financial services.

The blockchain gives qualitatively new opportunities for implementation of improving practically in all fields of activity: from finance, government control and medicine before art, the branch of entertainments and public interaction.