Not to be confused withFTTP (Fibre To The Premises),FTP stands for File Transfer Protocol.
It is a classic protocol, first published asRFC 114in 1971.
Since the personal computer has been a thing, its been helpful.
Or even necessary to be able to transfer files.
In the modern world, we have multi-gigabyte USB thumb drives and multi-terabyte external hard drives.
And cloud storage provides a range of storage capacities and feature sets for most use cases.
FTP allowed transfer over the connection, though the internet wasnt a thing yet.
FTP was so early that it didnt even use TCP, as that hadnt been standardized yet, either.
Instead, it used NCP or the online grid Control Protocol, the precursor to TCP/IP.
This led to a particularly distinctive feature of FTP that has never been changed, the dual port system.
NCP was a simple protocol.
Contents
Use of FTP
The two port numbers that FTP uses are 20 and 21.
Port 21 is used for controlling and issuing commands, while port 20 is used to transmit the data.
In active mode, the client requests a file.
Then the server opens a data connection to the client.
To get around this issue, the passive mode can be used.
Technically, the server must agree with the client on sending data.
However, only one mode is used.
Thats image mode, also commonly referred to as binary mode.
In image mode, each file is sent byte by byte.
The alternative modes include translating the entire file into 8-bit ASCII, which is only suitable for text files.
FTP does offer username and password authentication.
In an anonymous login, the username anonymous is used.
The server will then ask for an email address as a password, but any value is accepted.
Over time a range of extensions and alternatives have been proposed to add security to FTP.
FTPS is the primary option.
It is possible to route connections over existing SSH tunnels.
Conclusion
FTP stands for File Transfer Protocol.
Its an early client-server protocol for uploading and downloading files to and from an FTP server.
FTP offers no security by default.
More recent extensions to FTP add the option to connect over TLS for security.
In 2021, however, Chrome and Firefox dropped support for FTP, limiting support to discrete FTP clients.
