Which protocol is used for secure file transfer over a network?

The use of SFTP, or Secure File Transfer Protocol, for secure file transfer over a network is well justified. SFTP is specifically designed to provide secure file transfer capabilities by leveraging the SSH (Secure Shell) protocol. This includes features such as encryption, which ensures that both the data being transferred and the authentication credentials are securely protected during the transit.

Unlike standard FTP (File Transfer Protocol), which transmits data in plaintext, making it vulnerable to interception, SFTP encrypts the entire connection, offering a higher level of security that is crucial for sensitive data exchanges.

The other mentioned protocols serve different purposes: FTP is primarily for basic file transfers without security measures. HTTP (Hypertext Transfer Protocol) is used for transferring web pages but does not provide secure transfer on its own, though it can be secured with HTTPS. SMTP (Simple Mail Transfer Protocol) is used for sending emails rather than for file transfers. Hence, SFTP stands out as the correct choice for secure file transfer over a network.