In the related technology of electronic signature, the core is digital certificate, so what is digital certificate?
Digital certificate is a piece of identity certificate data issued by CA, which contains three parts: public key, private key and related identity information, and can be used for digital signature. The most important parts are public key and private key, which are a pair of keys based on asymmetric algorithm and have the following characteristics:
1.？ Encryption and decryption ability: Like symmetric encryption, it has the ability to encrypt data, and the whole encryption and decryption process involves two keys.
2.？ Two keys are unique: one key is called public key and the other key is called private key, and each pair of public and private keys is unique, so the current computer capacity is also difficult to crack.
3.？ Public plus private solution &; Private plus public solution: data encrypted with public key can only be decrypted with corresponding private key. Data encrypted with a private key can only be decrypted with the corresponding public key, and cannot be encrypted and decrypted independently.
4.？ Public key disclosure &; The private key is private: the public key is used to be made public on the network and can be obtained through technical means. The private key is stored independently and cannot be obtained by others.
5.？ Identify yourself: the public key can mark the identity of the holder, and the file that can be decrypted by the public key that confirms the identity can determine the encryption source.
In the application of electronic signature technology, the whole encryption and decryption process is as follows: