Proxy Server serves FTP clients下载

IntroductionIn this article I will talk about connecting FTP clients through Proxy Server. So, reader of this article should have a background about the following topics:TCP/IP protocol and Socket programming. File Transfer Protocol (FTP) - RFC 959. Proxy Server functionality - RFC 1919.Actually FTP clients can connect to FTP servers directly and can transmit and receive files or data directly through direct sockets connections, but in some cases security to FTP clients is needed and most of the internet clients access the internet from LAN network that is connected to the internet through Firewalls that support NAT (Network Address Translation) or full LAN isolation through proxy server.