TLS/SSL works by allowing the client and server to send each other encrypted data that only they can decrypt. TLS/SSL negotiates the terms of the encryption in a sequence of events known as the handshake. The handshake involves the following types of authentication:
  • TLS/SSL server authentication requires the server to authenticate itself to the client.
  • TLS/SSL client authentication is optional and requires the client to authenticate itself to the server after the server has authenticated itself to the client.