Public trust is a centralization exchange based on block chain technology, which can help data buyers and sellers to achieve efficient point to point data transactions, and has the advantages of not caching data, protecting user privacy and accessing rich data. The public chain of public trust chain, the public trust chain itself, is also a public chain supporting the development, application and distribution of digital money. Developers can develop and distribute digital money on the public credit chain, and improve the service and operation efficiency by utilizing the rich data in the public trust chain.