Ftp

FTP or File Transfer Protocol is a commonly used protocol for exchanging files over any network that supports the TCP/IP protocol (such as the Internet or an intranet).

There are two computers involved in an FTP transfer. The first computer is an FTP server. This computer listens on the network for connection requests from other computers. Another computer (called the client) can make a connection to the FTP server by using FTP client software.

Once connected, the client can do a number of file manipulation operations such as uploading files to the server, download files from the server, rename or delete files on the server and so on. Any software company or individual programmer is able to create FTP server or client software because the protocol is an open standard. Virtually every computer platform supports the FTP protocol. This allows any computer connected to a TCP/IP based network to manipulate files on another computer on that network regardless of which operating systems are involved (if the computers permit FTP access). There are many existing FTP client and server programs, and many of these are free.

Security problems

FTP is an inherently insecure method of transferring files because there is no way for FTP software to transfer data in an encrypted fashion and still conform to the protocol's specifications. What this means is that under most network configurations, user names, passwords, FTP commands and transferred files can be "sniffed" or viewed by someone else on the same network using a protocol analyzer (or "sniffer"). (Most Internet protocols like HTTP, SMTP and telnet have similar problems.) The common solution to this problem is to use SFTP (SSH File Transfer Protocol) which is based on SSH, or FTPS (FTP over SSL), which adds SSL encryption to FTP.

FTP and Web Browsers

Most recent web browsers and file managers can connect to FTP servers. This allows manipulation of remote files over FTP through an interface similar to that used for local files. This is done via an FTP URL, which takes the form ftp://<ftpserveraddress> (e.g., ftp://ftp.gimp.org/). A password can optionally be given in the URL, e.g.: ftp://<login>:<password>@<ftpserveraddress>. Most web-browsers require the use of passive mode FTP, which not all FTP servers are capable of handling.

This article is adapted from: wikiPedia.com.