FTP - File Transfer Protocol

- File Transfer Protocol (FTP), a standard Internet protocol, is the simplest way to exchange files between computers on the Internet.
- FTP is an application protocol that uses the Internets TCP/IP protocols.
- FTP is commonly used to transfer Web page files from their creator to the computer that acts as their server for everyone on the Internet.
- FTP is also commonly used to download programs and other files to your computer from other servers.
- Web browser can also make FTP requests to download programs you select from a Web page.
- FTP can also be used to update (delete, rename, move, and copy) files at a server.
- FTP can be run in active mode or passive mode, which control how the second connection is opened.
- In active mode the client sends the server, the IP address port number, that the client will use for the data connection, and the server opens the connection.
- Passive mode was devised for use where the client is behind a firewall and unable to accept incoming TCP connections.

The objectives of FTP are :
- to promote sharing of files (computer programs and/or data),
- to encourage indirect or implicit (via programs) use of remote computers,
- to shield a user from variations in file storage systems among hosts, and
- to transfer data reliably and efficiently.

Anonymous FTP

Thousands of hosts on the Internet run ftp servers that permit guests to login. Such servers usually contain data and software of interest to the general public. They are often called anonymous ftp servers because the guest login name is anonymous. To login to an anonymous ftp server, enter the name anonymous when prompted for a username or userid. When prompted for a password, enter your full e-mail address, unless the on-screen instructions specify an alternative guest password.