Purpose of the FTP protocol, the address format FTP – resource, FTP - server and client

File Transfer Protocol (FTP) is a standard network protocol used to transfer files from one host to another host over a TCP-based network, such as the Internet.

FTP is built on a client-server architecture and uses separate control and data connections between the client and the server. FTP users may authenticate themselves using a clear-text sign-in protocol, normally in the form of a username and password, but can connect anonymously if the server is configured to allow it.

For secure transmission that hides (encrypts) the username and password, and encrypts the content, FTP is often secured with SSL/TLS ("FTPS"). SSH File Transfer Protocol ("SFTP") is sometimes also used instead, but is technologically different.

One of the possible forms of a URL is an FTP URL, which begins with ftp: as the protocol part. Example:

ftp://ftp.funet.fi/pub/standards/RFC/rfc959.txt

An FTP URL designates a file or a directory on an Internet host accessible using the FTP protocol.

Such URLs are often used in Web documents in order to refer to a resource which is downloadable from a public FTP server. Less importantly, they can also be used to refer to a resource on a non-public area, so that a password is required.

The syntax of FTP URLs

According to the specification of URL formats, RFC 1738, an FTP URL is of the form

ftp://user:password@host:port/path

so that some or all of the parts user:password@,:password,:port and /path may be excluded.

FTP-client - a program to simplify access to the FTP server.

FTP-server is an ordinary computer, which is connected to the Internet anywhere and are public files. And in order to copy the data files on our computer needs a special data transfer protocol - FTP. With the help of the program - FTP-client.