In Active FTP who sends the PORT command?

In Active FTP, the client sends the PORT command to the server, specifying an ephemeral port for the server to initiate the data connection back to the client. This distinguishes Active FTP from Passive FTP, where the server provides the port. The server does not send PORT, and the command is a key part of Active FTP. Exact extract: "In Active FTP, the client sends a PORT command to the server, specifying the IP address and port number for the data connection... The server then initiates the data connection to the client’s specified port."