Introduction - If you have any usage issues, please Google them yourself
FTP protocol is based on TCP/IP file transfer protocol that is used in the network for file transfer. FTP is a TCP/IP to a specific application, it works in the seventh layer of OSI model, TCP model for the fourth layer, namely, the application layer, using TCP transport instead of UDP, FTP client and server must establish a connection before the After a "three-way handshake" process, it brings the significance of the connection between the client and the server is reliable, but also connection-oriented, for data transmission to provide a reliable guarantee for