Block chain-based under-chain capacity expansion technology

The invention discloses a blockchain-based under-chain capacity expansion technology, which comprises a blockchain under-chain capacity expansion scheme, a plasma smart contract-based data integrity auditing protocol, a batch auditing scheme and a security definition, and is characterized in that the blockchain under-chain capacity expansion scheme comprises 0-layer capacity expansion, on-chain capacity expansion and under-chain capacity expansion; the 0-layer capacity expansion improves the expandability of the block chain by changing a bottom-layer data transmission protocol of the block chain; the on-chain capacity expansion comprises a data layer improvement scheme, a consensus layer improvement scheme and a network layer improvement scheme; the under-chain capacity expansion is to change in an application layer so as to improve the expandability. By adopting the under-chain capacity expansion technology based on the block chain, privacy protection is enhanced, network delay is reduced, processing efficie