What happens if part of an FTP message is not delivered to the destination?
- The message is lost because FTP does not use a reliable delivery method.
- The FTP source host sends a query to the destination host.
- The part of the FTP message that was lost is re-sent.
- The entire FTP message is re-sent.
Because FTP uses TCP as its transport layer protocol, sequence and acknowledgment numbers will identify the missing segments, which will be re-sent to complete the message.