On May 27, Cao Jiannong, head of the Department of Electronic Computing at the Hong Kong Polytechnic University and founder of Huawei's blockchain, said at the high-end dialogue on the "blockchain: the cornerstone of digital civilization" at the 2019 Expo, blockchain technology will be big data. Support for sharing and exchange. He said: "Big data is not that data can be used very well. Big data is diverse. They come from different fields. When we solve a problem, we need to use data in many different fields and how to share our data. This requires blockchain technology to support big data sharing and exchange.” Cao Jiannong also said that the blockchain has three properties: decentralization, transparency and unchangeable. Decentralization can ensure privacy and transparency. Sexuality and immutability, which guarantees the authority of the data, everyone trusts each other, and the blockchain can meet these requirements when data is shared and exchanged.