CA certificate

CA certificate is an e-commerce certification body, also known as e-commerce certification center. It is the authority responsible for issuing and managing digital certificates. As a trusted third party in e-commerce transactions, it is responsible for verifying the legitimacy of public keys in public key systems.

The contents of the certificate include: information of the electronic visa authority, public key user information, public key, authority signature and validity period, etc. At present, the format and verification method of certificates generally follow the international standard X.509

Self-issued certificate

What is issued by the server itself and by an authority to prove its identity is not trusted by the default client. A certificate is a self-issued certificate, not a self-signed certificate, in the following cases: when a CA changes the key, there may be two key pairs (a new key pair and an old key pair), and it may happen that an old public key is issued with a new private key or a new public key is issued with an old private key. The certificate thus formed is a self-issued certificate, but not a self-signed certificate.

Self-service visa

A self-signed certificate is a certificate issued by a signing entity, that is, the issuer and the certificate subject are the same.