Question

in the context of ftp over explicit tls (ftpes), which command is used to encrypt the data connection for actual file transfers after upgrading an unsecure connection to a secure one?

a ssh
b auth tls
c pasv
d prot

Explanation:

Analyze the FTPES connection upgrade process

In FTP over Explicit TLS (FTPES), a client connects to the standard FTP port (usually port 21) unencrypted. The client then upgrades the control connection to a secure TLS session by sending the AUTH TLS command.

Identify the command for data connection encryption

Once the control connection is secured, the client must specify whether the subsequent data connections (used for actual file transfers and directory listings) should also be encrypted. The command used to set the protection level of the data channel is PROT (Data Channel Protection Level).

Evaluate the options

• A SSH: Secure Shell is an entirely different protocol, not an FTP command.
• B AUTH TLS: This command secures the control connection, not the data connection.
• C PASV: This command enters passive mode for data transfer but does not handle encryption.
• D PROT: Sending PROT P (Private) secures the data channel with TLS encryption.

Answer:

• (A) SSH
• (B) AUTH TLS
• (C) PASV
• (D) PROT (Correct answer)