The Internet provides many services, including e-mail, file transfer FTP, interactive browsing of WWW information, remote login Telnet, bulletin board BBS, etc. (Recommended learning: web front-end video tutorial)
FTP (File Transfer Protocol, File Transfer Protocol) is one of the protocols in the TCP/IP protocol group. The FTP protocol consists of two components, one is the FTP server, and the other is the FTP client.
The FTP server is used to store files, and users can use the FTP client to access resources located on the FTP server through the FTP protocol.
When developing a website, the FTP protocol is usually used to transfer web pages or programs to the Web server. In addition, because FTP transmission efficiency is very high, this protocol is generally used when transmitting large files on the network.
By default, the FTP protocol uses TCP ports 20 and 21, of which 20 is used to transmit data and 21 is used to transmit control information.
However, whether to use 20 as the port for data transmission is related to the transmission mode used by FTP. If active mode is used, the data transmission port is 20; if passive mode is used, the specific port used ultimately depends on the server side. Negotiate with the client to decide.
Like most Internet services, FTP is also a client/server system.
Users connect to a server program running on a remote computer through a client program.
Provide services in accordance with the FTP protocol. The computer that transfers files is the FTP server, and the computer that connects to the FTP server and follows the FTP protocol to transfer files with the server is the FTP client.
To connect to the FTP server, users must use FTP client software. Usually Windows comes with the "ftp" command, which is a command line FTP client program. Other commonly used FTP client programs include FileZilla, CuteFTP, Ws_FTP, Flashfxp, LeapFTP, Meteor Shower-Maoyan, etc.
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