What is blockchain?
Warning. This article was published in 2015 and is waiting to be updated.
Blockchain is a distributed database that can be accessed by anyone. It is otherwise known as “distributed ledger technology” because there is no centralized authority or regulator that can manage blockchain at its own discretion.
How is blockchain different from a classical database?
A classic database is stored on dedicated servers that are controlled by the organization that owns the database. Blockchain is not controlled by any one person or organization, and it is its distributed architecture that ensures its security. If some of the computers on which the blockchain is stored are hacked, the entire system will not be affected in any way, which is unthinkable for a classic database.
How does blockchain work?
Theoretically, anything from monetary transactions to the complete collection of the world’s literature can be written to a blockchain. In order for the data to enter the blockchain, it must be verified, that is, verified for authenticity. In the case of bitcoin and remittances, this is done by so-called miners
. Once they verify the validity of a transaction, they write it into a block, and then it stays in the blockchain forever, and anyone can verify its authenticity. However, any such transaction must receive several confirmations from independent sources before it is considered valid.
Where is the blockchain stored?
Blockchain can be stored anywhere, and is stored everywhere. There are special nodes(nodes
) on the network that store the full up-to-date version of the blockchain, while the other nodes just access them when they need to verify something. You can download the full version of the blockchain from public sources, then it will be stored by you as well.
Why is there so much hype around blockchain?
Blockchain is often compared to the internet because of its ability to change the world. People now need to keep a huge staff of lawyers, notaries, regulators, bankers, and other bureaucrats to certify and confirm events, such as a paycheck or the sale of an apartment. Blockchain technology is able to do all their work completely automatically, thus eliminating the very need for intermediaries.
Where is blockchain being used right now?
Blockchain technology is used in almost every cryptocurrency, making it work. Blockchain is also beginning to be actively implemented in banking systems, property registration systems and various government registries, supply chain management, and areas such as digital identity, energy, voting, gaming, the Internet of Things
How is open blockchain different from private blockchain?
Open blockchain is available to everyone, while private blockchain is available only to a select few. There can be so many different blockchains, some of which are open and others of which are closed. They can’t interoperate yet because each blockchain can implement its own rules of operation, and the rules of one blockchain may directly contradict the rules of another.
How can multiple blockchains be made to interact?
A variety of options have been proposed to solve this problem. The most popular of these are so-called side
chains, special blockchains. The latter are needed solely to connect one blockchain with another, bypassing the possible contradiction between their rules.