Configuration Guide FTP Client Configuration
Active Mode
Figure 2 Port (active) Mode
In this mode, FTP server actively establishes data connection with FTP client through the following four steps:
The client uses the source port 5150 to communicate with the port 21 of server. The client requests to establish
connection and notify the server that it is using the port 5151.
Upon receipt of the request, the server responds with OK (ACK) message. The client and server then exchange
control signals through the control port.
The server opens the port 20 as the source port for sending data to the port 5151 of client.
The client replies and the transfer process ends.
Passive Mode
Figure 3 PASV (passive) Mode