How does Secure Socket Layer (SSL) work?

SSL works by encrypting data transferred between a client and a server, ensuring secure communication over the internet.

Secure Socket Layer (SSL) is a protocol used to secure communications between a web browser (the client) and a web server. It uses encryption to ensure that the data transferred between the client and the server is private and integral. This is particularly important when sensitive information, such as credit card numbers or personal details, are being transmitted.

SSL operates using a system of trusted certificates. When a client connects to a server that uses SSL, the server presents a certificate to the client. This certificate contains a public key, which the client uses to encrypt data before sending it to the server. The server then uses its private key to decrypt the data. This process is known as asymmetric encryption.

The certificate also contains information about the server's identity, which is verified by a trusted third party known as a Certificate Authority (CA). The CA confirms that the server is who it claims to be, providing a level of trust for the client. If the server's certificate is not trusted, the client's browser will display a warning message.

In addition to encryption, SSL also provides authentication and integrity. Authentication is achieved through the use of certificates, as described above. Integrity is ensured through a process called hashing. Before data is sent, it is processed to create a unique hash value. This value is sent along with the data. When the data is received, it is processed again to create a new hash value. If the new value matches the one sent with the data, the receiver knows that the data has not been tampered with during transmission.

In summary, SSL works by using encryption, authentication, and integrity checks to secure data transferred between a client and a server. It is a vital component of secure internet communication, protecting sensitive information from interception or tampering.