This step adds an identity verification process.
In traditional public-key cryptography, signatures are achieved by encrypting messages using a private key.
In identity-based signature schemes, signatures are implemented by using private keys to encrypt messages and identity information. In this scheme, the user's identity information can be used as part of the public key, while the private key is generated and distributed by the identity certification authority. The process of authentication is a key step in identity-based signature schemes.