What is the data transfer port used by File Transfer Protocol (FTP) for control?

What is the data transfer port used by File Transfer Protocol (FTP) for control?

• A. 20
• B. 21
• C. 22
• D. 23

Answer: (B)

File Transfer Protocol (FTP) uses port 21 for control commands. This port is responsible for initiating commands and managing the session between the client and server. When a client wants to establish a connection to an FTP server, it connects to this control port to send commands such as login credentials and directory navigation instructions. Port 20 is used for the data transfer in active mode, but the control commands specifically utilize port 21. Ports 22 and 23 do not relate to FTP; port 22 is typically used for Secure Shell (SSH) and port 23 is used for Telnet, both of which serve different purposes in network communication. Understanding the roles of these ports is essential for configuring and troubleshooting FTP services effectively.

File Transfer Protocol (FTP) uses port 21 for control commands. This port is responsible for initiating commands and managing the session between the client and server. When a client wants to establish a connection to an FTP server, it connects to this control port to send commands such as login credentials and directory navigation instructions.

Port 20 is used for the data transfer in active mode, but the control commands specifically utilize port 21. Ports 22 and 23 do not relate to FTP; port 22 is typically used for Secure Shell (SSH) and port 23 is used for Telnet, both of which serve different purposes in network communication. Understanding the roles of these ports is essential for configuring and troubleshooting FTP services effectively.