COMPUTER NETWORKING

Detailed explanation-1: -The FTP protocol typically uses port 21 as its main means of communication. An FTP server will listen for client connections on port 21. FTP clients will then connect to the FTP server on port 21 and initiate a conversation.

Detailed explanation-2: -Port 21 and File Transfer Port 21 is commonly associated with FTP. FTP has been assigned to Port 21 by the Internet Assigned Numbers Authority (IANA). The IANA also oversees global IP address allocation. FTP is often thought of as a “not secure” file transfer protocol.

Detailed explanation-3: -Anyway, port 21 is used for FTP protocol (and FTPS with explicit TLS/SSL encryption). Port 22 is used for SSH/SFTP protocol. WinSCP automatically uses the correct port number, when you specify the respective protocol. Usually it is not necessary to specify the port number explicitly.

Detailed explanation-4: -Port numbers 21 and 20 are used for FTP. Port 21 is used to establish the connection between the 2 computers (or hosts) and port 20 to transfer data (via the Data channel).

Detailed explanation-5: -What Are Ports? In terms of FTP, ports are communication endpoints. Ports allow the connection and transfer of data to happen between your computer and a server. To connect to a specific server, you need to know that server’s IP address.