FTP
Definition
FTP, short for File Transfer Protocol, is a standard network protocol used to transfer files between a client and a server over a TCP/IP network. It allows users to upload, download, rename, and delete files on remote servers, making it one of the oldest and most widely recognized methods of file sharing across networks.
FTP typically operates through a client application that connects to an FTP server using credentials. While it has been largely replaced by more secure methods, it remains in use for legacy systems, website management, and file distribution.
Advanced
FTP operates over TCP, typically on ports 20 and 21. It supports two modes: active and passive. Active mode requires the server to establish a data connection back to the client, while passive mode lets the client initiate both connections, helping navigate firewalls and NAT (Network Address Translation).
However, standard FTP does not encrypt traffic, leaving data and credentials exposed. Secure alternatives such as FTPS (FTP Secure, which uses SSL/TLS) and SFTP (SSH File Transfer Protocol, though technically a different protocol) are preferred in modern environments. Advanced file transfer setups often include automation, logging, and integration with enterprise workflows.
Why it matters
Use cases
Metrics
Issues
Example
A hosting provider offered FTP access for customers to manage website files. To address security risks, the provider transitioned to FTPS, ensuring all file transfers were encrypted while retaining FTP’s familiar functionality.