1. Separation of public and private keys: Blockchain uses asymmetric encryption to divide users' keys into private keys and public keys, in which public keys are published in the network for data interaction and address access, while private keys are kept in users' hands to protect their own data and assets. This separation of public key and private key is an encryption mechanism with high security factor.

2. Multi-signature: In the application of digital signature, sometimes multiple users need to sign and authenticate the same file. For example, the statement issued by a company involves many departments, such as finance department, development department, sales department and after-sales service department, which need to be signed, so these departments need to sign the statement documents.