As we all know, SSL certificates are mainly digital certificates used to encrypt network communications, ensuring the security of data transmission between users and websites. Choosing an SSL certificate is an important step in ensuring the security of your website. So why deploying an SSL certificate can ensure the security of data transmitted between users and websites? What is the principle? The details are as follows!
The principle of SSL certificate (Secure Socket Layer Certificate) is to provide security guarantee for network communication by using a combination of asymmetric encryption and symmetric encryption.
Asymmetric encryption
The SSL certificate uses an asymmetric encryption algorithm, including a public key and a private key. The public key is used to encrypt data and the private key is used to decrypt data. The server generates a pair of keys, puts the public key in the certificate, and the private key is kept securely on the server.
Digital certificate
The SSL certificate is issued by a trusted third-party organization (CA, Certificate Authority) and contains the server's public key and other information. Certificates verify their authenticity and integrity through digital signatures.
Handshake process
When establishing an SSL connection, the client sends a connection request to the server, and the server returns a certificate containing its public key. The client verifies the validity of the server certificate through the root certificate of the CA organization. If the verification passes, the client generates a temporary symmetric key, encrypts it with the server's public key, and sends it to the server. The server uses the private key to decrypt and obtain the symmetric key. After that, both parties use the symmetric key to encrypt and decrypt the communication content.
Encrypted communication
Once the handshake process is completed, the communication between the client and server will be encrypted and decrypted using symmetric keys, ensuring data confidentiality and integrity. This process is completed at the transport layer and is transparent to upper-layer applications.
By using an SSL certificate, you can ensure the security of data during transmission. SSL certificates are an important tool for establishing secure connections and protecting user privacy, so they are widely used in websites, e-commerce, online payments and other fields.
