A company requires remote manipulation of their file directory and file transfers over a network. While assessing the use of FTP, the network administrator must understand the use of ports by the FTP service. Which pair of ports does FTP traditionally use for command and data transfer?
Ports 80 for commands and 443 for data transfer
Ports 22 for both commands and data transfer
Ports 21 for commands and 20 for data transfer
Ports 20 for commands and 21 for data transfer