What is the last action performed during the TLS handshake process before data transmission?

• A. Session establishment
• B. Data encryption
• C. Decryption of keys
• D. Handshake completion

Answer: (B)

During the TLS handshake process, the last action performed before data transmission begins is the establishment of a secure connection between the client and server. This final step ensures that both parties agree on the parameters of the secured communication, such as the defined encryption methods and session keys that will be used for the subsequent data transmission.

Once the handshake is completed, the session is established, but data encryption does not occur as the last action—rather, it happens afterward, utilizing the agreed-upon keys. Handshake completion signifies that both parties are ready to exchange encrypted data, while decryption of keys involves the process of using private keys, which is part of the protocol earlier in the handshake. Thus, the handshake completion is considered the final vital action that solidifies the secure connection before actual data is transmitted over it.