FTP stands for File Transfer Protocol and is used primarily to transfer files between different computers via the internet. For example, if you have a bunch of files you want to upload to a website, you can use FTP to transfer files to the website hosting server directly.

File Transfer Protocol (FTP) allows you to transfer data between computers over an internet connection and remotely store files on an FTP server. Sure, there have been considerable advances in security and cloud-based file transfer services since 1971 when FTP was introduced.

FTP isn’t maintained or updated: While organizations still opt to use FTP, this protocol was never intended to be used in 2019. Other file transfer protocols, like FTPS, SFTP, HTTPS, and AS2, have since been created to replace FTP and protect data in transit between recipients.

FTP allows new web pages that are created by an individual to show up on the internet. It allows the web pages to transfer to the server so that others can access them. Using an FTP client we can upload, download, delete, move, rename and copy the file on a server.

Examples of FTP clients that are free to download include FileZilla Client, FTP Voyager, WinSCP, CoffeeCup Free FTP, and Core FTP. Many people have used FTP before without even noticing it. Once you have accessed the FTP server through your FTP client, you can now transfer files.

Passive FTP is an FTP mode that can be requested by a client to alleviate the issues caused by client-side firewalls. Both the server and the client must support passive FTP for this process to work. When passive FTP is used, the client will initiate the connection to the server.

FTP Connection Modes: Active vs Passive Mode

1. In the main menu, click on Edit > Settings….
2. Select Connection > FTP from the list on the left side.
3. Check the Transfer mode and modify if needed.
4. Click on OK.

In passive mode FTP, the FTP client initiates both connections to the server. This method of FTP is insecure, as a random unprivileged port is opened on the Server. This is a potential security issue and it isn’t advisable to use the Passive mode of FTP.

In the passive mode, the client uses the control connection to send a PASV signal to the server. FTP server sends back IP address and server port number. In active FTP, client establishes the command channel and the server establishes the data channel. Passive mode is used as a default mode of a browser.

In active mode FTP the client connects from a random unprivileged port (N > 1023) to the FTP server’s command port, port 21. Then, the client starts listening to port N+1 and sends the FTP command PORT N+1 to the FTP server.

To set passive mode FTP in Internet Explorer, click “Internet Options” in the “Tools” menu, click the “Advanced” tab, then check the “Use Passive FTP” box. Using passive mode should alleviate any FTP connectivity problems you may have.

Essential ftp Commands

A verb is in the passive voice when the subject of the sentence is acted on by the verb. For example, in “The ball was thrown by the pitcher,” the ball (the subject) receives the action of the verb, and was thrown is in the passive voice.

Here’s how passive mode works in a nutshell:

1. The client connects from a random port to port 21 on the server and issues the PASV command. The server replies, indicating which (random) port it has opened for data transfer.
2. The client connects from another random port to the random port specified in the server’s response.

It is not possible to “disable” passive mode on the server. The decision to use passive mode is made by the client exclusively. You will have to instruct your client to not use passive connections, but that may prove impossible/dangerous for them, if they are behind a firewall or router that is not ftp-aware.

SFTP doesn’t use passive mode – that’s for FTP or FTPS (you might be talking about FTPS). Hundreds of connections from a client may not work as there is usually a limit to the number of network connections you can open on a client machine.