File Transfer Protocol (FTP) is a standard network protocol used to transfer files between computers. It is built on a client-server model using separate control and data connections between the client and server. Users who have been granted access can receive and transfer files in the FTP server, also known as the FTP host/site.
What is FTP used for?
FTP is a helpful tool for moving information from the computer a user is currently working on to the server where a website is hosted. For instance, If a user wants to install WordPress on a web server, FTP is needed to copy the files over.
It’s also useful for sharing files between people. One user may upload a file to an FTP server then share a link to it with another person. This usage of FTP is becoming less common as cloud services provide an easy way to share files. However, some users may prefer to have their files hosted on a home server and use FTP to enable it.
How FTP works
An FTP connection needs two parties to establish and communicate on the network. To do this, a user must receive permission by providing credentials such as a username and password to the FTP server. (In some cases, a public FTP server may not require credentials to access their files.)
There are two distinct communication channels while establishing an FTP connection:
- Command channel: The channel in which the instruction and response is initiated.
- Data channel: The channel in which the data is distributed.
Along with communication channels, there are two modes in which FTP operates that determine how the data connection is established:
- Active mode: To get a transfer for file, an authorized user will use the protocol to request creating changes in the server. In return, the server will grant the access. Distribution in active mode may become problematic if a firewall is protecting the user’s machine. The firewall may not allow any unauthorized sessions from an external party.
- Passive mode: Passive mode is used if the firewall issue mentioned above occurs. In this mode, the user establishes both the command and data channel. The server listens rather than attempting to create a connection back to the user.
The future of FTP
FTP was originally developed to send and receive files in text-based computers and networks around the mid-1980s. It existed as one of the original programs for accessing information on the internet before the use of HyperText Transfer Protocol (HTTP) became popular for accessing web pages. Because of this, a PC’s web browser can be used to access FTP servers to transfer files. Virtually every computer platform supports the FTP protocol.
Today, FTP is largely considered to be an outdated protocol because it is no longer updated and has been replaced with more secure file transfer protocols including FTPS, SFTP, and HTTPS. In November 2020, support for the FTP protocol was deprecated in Google Chrome.