Ruijie RG-S2900G-E Series, Руководство по настройке

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Configuration Guide FTP Client Configuration
This mode is generally configured through passive command. Since FTP server is passively connected to FTP client, it is
referred to as passive connection. This process involves the following four steps:

1. In passive mode, the client initializes the control signal connection and uses the source port 5150 to establish
connection with port 21 of server. The client uses the passive command to request the server to enter passive
mode.

2. The server agrees to enter PASV mode, randomly selects a port number greater than 1024 and notifies the client.

3. Upon receipt of such message, the client will use the port 5151 to carry out data communication with the port 3268
as provided by the server. Here, 5151 is the source port and 3268 is the destination port.

4. Upon receipt of message, the server will transfer data and reply with ACK (OK).
When data connection is established between client and server, data upload and download can be performed, while the
client can also carry out certain file system operation on the server.
The control connection for transferring commands and replies exists all along, and the data connection is
only established when needed. The application of PASV mode or PORT mode is determined only by FTP client,
which will send relevant commands to use different modes of data connection. By default, Ruijie FTP client uses
passive mode.
FTP Transfer Mode
There are two FTP transfer modes: text (ASCII) transfer mode and binary (BINARY) data transfer mode. Currently, Ruijie
FTP Client supports both modes, and the default mode is BINARY.
Text Mode
The difference between ASCII mode and BINARY mode is the handling of new line. In ASCII mode, the new line is
converted to the carriage return character of local device, such as \n for Unix, \r\n for Windows and \r for Mac.
Binary Mode
BINARY mode can be used to transfer executable files, compressed files and image files without any data processing.
Taking the example of transferring text file from Unix to Windows, the BINARY mode will not convert the new-line
character from \r (Unix) to \r\n, and thus there is no line shifting when this file is viewed on Windows (you can only see
black boxes). Since there is no new-line processing, the BINARY mode is faster than text mode, and all ASCII values can
be transferred without error.
If text format conversion is needed, such as the conversion between Unix-formatted text and
Dos-formatted text, there are many tools available. Therefore, the Binary mode is generally the default mode of FTP.