Engine academy: blockchain classification
According to different ways of node participation, blockchain technology can be divided into public chain, alliance chain and private chain.
The chain of public
A public chain, as the name implies, is a public blockchain. The public chain is completely public, and anyone can act as a node in the network without anyone giving permission or authorization. In the public chain, each node can freely join or exit the network, participate in the reading and writing of data on the chain, execute transactions, and participate in the consensual process in the network, that is, to decide which block can be added to the main chain and record the current network state. Public chain is a completely decentralized blockchain, which guarantees the security of transactions on the chain by means of encryption algorithm in cryptography. A public chain, also known as a public chain, is an unlicensed chain that can participate in and exit without permission. At present, the most typical representative applications include bitcoin, Ethereum and so on. Due to its completely decentralized and mass-oriented nature, the public chain is usually suitable for \"virtual cryptocurrency\" and some financial services and e-commerce for the public.
Alliance chain is not completely decentralized, but a kind of multi-centralized or partially decentralized blockchain. When a blockchain system is running, its consensus process may be controlled by certain specified nodes. The data on the alliance chain account book is different from the full disclosure of the public chain. Only the member nodes of the alliance can access, and the read and write permissions on the chain, participation in accounting rules and other operations need to be jointly decided by the member nodes of the alliance. As the participants in the league chain scenarios to form a coalition, participate in the consensus of the node will be a lot less than the level of public chain, and is generally for a business scenario, prove so consensus agreement is generally not used and the amount of similar mining mechanism, at the same time does not necessarily need tokens as incentive mechanism, but using PBFT, RAFT such applicable to more centralized consensus algorithm and high efficiency. At the same time, the alliance chain has a great difference from the public chain in terms of transaction time, status and transaction number per second, so it has higher security and performance requirements than the public chain.
Alliance chain is a kind of permission chain, which means that not anyone can join the network freely, but it needs certain permission to join as a new node.
The chain of private
Private chain means that all write permissions on the whole block chain are only in the hands of one organization, while read permissions can be open to the public or restricted arbitrarily according to the circumstances. Therefore, the application scenario of private chain is generally a single enterprise internal head office to branch management aspects, such as database management and auditing. Compared to public and alliance chains, private chains are valued primarily for providing a secure, traceable, tamper-proof platform that protects against both internal and external security attacks.