Which of the following ports is used by FTP for data transfer?

Which of the following ports is used by FTP for data transfer?

• A. 21
• B. 23
• C. 80
• D. 110

Answer: (A)

The File Transfer Protocol (FTP) uses port 21 for establishing a connection and initiating commands between the client and the server, which encompasses user authentication and commands for file transfers. When a client connects to an FTP server, the connection is typically initiated on this port, allowing the user to send commands for uploading or downloading files. Port 21 specifically handles the control commands necessary for managing the FTP session. In addition, after the initial command is established on port 21, FTP typically opens a second port for the actual data transfer, depending on whether it operates in active or passive mode. Nonetheless, port 21 is universally recognized as the standard for FTP command control, making it the correct answer in this context. Other mentioned ports serve different protocols, with port 23 used for Telnet, port 80 for HTTP (web traffic), and port 110 for POP3 (email retrieval).

The File Transfer Protocol (FTP) uses port 21 for establishing a connection and initiating commands between the client and the server, which encompasses user authentication and commands for file transfers. When a client connects to an FTP server, the connection is typically initiated on this port, allowing the user to send commands for uploading or downloading files. Port 21 specifically handles the control commands necessary for managing the FTP session.

In addition, after the initial command is established on port 21, FTP typically opens a second port for the actual data transfer, depending on whether it operates in active or passive mode. Nonetheless, port 21 is universally recognized as the standard for FTP command control, making it the correct answer in this context. Other mentioned ports serve different protocols, with port 23 used for Telnet, port 80 for HTTP (web traffic), and port 110 for POP3 (email retrieval).