11.1.1.4.1. Procedure – Procedure of encrypted communication and authentication

1. The sender and the receiver select a method (encryption algorithm) for encrypting the communication.

2. The sender authenticates the receiver by requesting its certificate and public key. Optionally, the receiver can also request a certificate from the sender, thus mutual authentication is also possible. During the handshake and authentication the parties agree on a symentric key that will be used for encrypting the data communication.

3. The sender encrypts his message using the symmetric key.

4. The sender transmits the message to the receiver.

5. The receiver decrypts the message using a symmetric key.

6. The communication between the parties can continue by repeating steps 3-5.