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FTP configuration
FTP overview
Introduction to FTP
The File Transfer Protocol (FTP) is an application layer protocol used to share files between server and
client over a TCP/IP network.
FTP uses TCP ports 20 and 21. Port 20 is used to transmit data, and port 21 is used to transmit control
commands. For more information about FTP basic operations, see RFC 959.
FTP transfers files in the following modes:
•
Binary mode—Transfers files as raw data, such as
.app
and
.bin
files.
•
ASCII mode—Transfers files as text, such as
.txt
,
.bat
, and
.cfg
files.
FTP operates in either of the following modes:
•
PORT mode—Active mode, in which the FTP server initiates a data connection request. This mode
is unavailable when the FTP client is behind a firewall.
•
PASV mode—Passive mode, in which the FTP client initiates a data connection request. This mode
is unavailable when the server side does not allow the client to connect to a random unprivileged
port (>1024).
The FTP operation mode varies with FTP client programs.
FTP operation
FTP adopts the client/server model. Your device can function either as the client or the server. See
.
•
When the device serves as the FTP client, a user can Telnet to it from a PC, and execute the
ftp
command to establish a connection to the remote FTP server on the PC to upload/download files
to/from the PC.
•
When the device serves as the FTP server, a user can FTP to the device from a PC that runs the FTP
client and upload/download files to/from the device.
Figure 36
Network diagram
When the device serves as the FTP client, you need to perform the following configuration:
