Don Tapscott explains why blockchain, the technology underpinning the cryptocurrency, have the potential to revolutionize the world economy.
Blockchain is the core technology behind bitcoin. At its heart is a distributed data store. Anyone who participates in this network has their own data store that stores all of the transactions that ever happened on the network (this is also known as the distributed ledger).
Entries are stored within a cryptographic chain of blocks. At every stage, the network of participants must agree about the latest block of transactions. Agreement is reached through a process of majority consensus, eliminating duplicate entries, double spending etc. This process and the cryptographic layering of the blocks makes the agreed blockchain irreversible and immutable. The ‘history’ of events within this technology cannot be modified by any one of the participants without majority consensus from the group.
Private blockchains are deployed either within an organization or shared among a known group of participants. They can be limited to a predefined set of participants. In this case, no one else can access them or the data residing in them. They can be secured in a similar way to securing other integrated enterprise applications (e.g. firewalls, VPN etc).
A Smart Contract is code that is deployed to the blockchain. Each smart contract contains code that can have a predefined set of inputs. Smart contracts can also store data. Following the distributed model of the blockchain, smart contracts run on every node in this technology, and each contract’s data is stored in every node. This data can be queried at any time. Smart Contracts can also call other smart contracts, enforce permissions, run workflow logic, perform calculations etc. Smart contract code is executed within a transaction – so the data stored as a result of running the smart contract (i.e. the state) is part of the blockchain’s immutable ledger.
Mining is used a proof of work for participants in the blockchain. Whenever a block of transactions is to be agreed, every participating node attempts to ‘mine’ the block (a mathematical algorithmic process that requires extensive CPU capacity). In public blockchains successful mining is rewarded with a cryptocurrency token.