There are many formats of digital certificates, mainly X.509v3( 1997), X509v4( 1997), X.509v 1( 1988) and so on. The more commonly used version is t utrec.x.509v3
Formulated by the International Telecommunication Union, including the serial number, validity period and public key of the certificate. No matter which version of digital certificate, as long as it is obtained, users can apply it to network security.
Extended data:
The basic architecture of digital certificate is public key PKI, which uses a pair of keys to encrypt and decrypt. The key includes a private key and a public key. The private key is mainly used for signing and decrypting. It is customized by the user and only known by the user.
The data signature of a digital certificate is similar to the encryption process. After data encryption, only the receiver can open or change the data information, add its own signature, and then transmit it to the sender. The receiver's private key is unique and private.
Baidu Encyclopedia-Digital Certificate