It has been more than 10 years since Satoshi Nakamoto published his famous paper entitled'Bitcoin: a peer-to-peer electronic cash system', which set the foundation of blockchain technology.Accompanied by the price volatility of bitcoins from 2017 to 2018, blockchain has been a hot word on the internet, and particularly hot in China.Blockchain offers a distributed and secure system for data storage and value transactions.Its applications are springing up in multiple fields.