FTP, or File Transfer Protocol, is a standard network protocol used for transferring files between a client and a server on a computer network. It provides a straightforward method for users to upload, download, and manage files stored on remote servers. FTP operates on the application layer of the TCP/IP protocol suite and is widely used for sharing files over the internet and within private networks.
The primary uses of FTP include:
- File Transfer: FTP allows users to upload files from their local computers to a remote server or download files from a server to their local computers.
- File Management: Users can create, delete, rename, and move files and directories on remote servers using FTP commands.
- Backup and Storage: FTP is often used for backing up important files and data to remote servers, providing a secure offsite storage solution.
- Software Distribution: Many software vendors use FTP to distribute updates, patches, and downloadable software packages to their users.
- Web Publishing: FTP is used for uploading web content (HTML files, images, scripts) to web servers, enabling website management and updates.
An example of FTP use is a web developer using FTP to upload new website content to a web server. By connecting to the server using an FTP client, the developer can transfer HTML, CSS, and other files necessary to update the website’s design and functionality. FTP ensures that files are transferred securely and efficiently, supporting ongoing website maintenance and content updates.
FTP uses port numbers to establish connections between clients and servers. The default FTP port for the control connection is TCP port 21. This port handles commands and responses between the client and server, facilitating file transfer operations. In addition to the control connection, FTP also uses a separate data connection (established on TCP port 20 in active mode or dynamically assigned in passive mode) for transferring file data.
FTP commands are used to interact with the FTP server and perform various operations such as navigating directories, transferring files, setting file permissions, and managing sessions. Examples of FTP commands include GET (to download a file), PUT (to upload a file), DELETE (to remove a file), LS (to list directory contents), CD (to change directory), and MKDIR (to create a new directory). These commands enable users to efficiently manage files and directories on remote servers using FTP clients.
