How Does FTP Work: Low Overhead File Transfers
What Is a File Transfer?
One of the original reasons for the invention of the Internet was to have the ability to transfer information from one location to another. Some of the original developers wanted to circumvent sending information via the US post office. They felt that they could develop a faster transfer approach using the limited Internet that existed. The original transfers were slow because bandwidth was limited, but the transfers had a minimum overhead; even security was not an issue. By 1980, the FTP protocol was defined as RFC (Request For Comment) 765.
The Way FTP Works
Looking at how does FTP work, you start with the fact that FTP is an unsecured protocol. That alone will tell you that it is an older protocol, because in today’s Internet operations, security is a big concern. This means that when you transfer files, they are not encrypted and even names and passwords fly over the Internet where anyone can read them.
The actual file transfer takes place using FTP instead of HTTP in the URL address. For instance, to connect to an ftp server, you would type, FTP://200.14.1.1. FTP transfers, however, will be faster than other type of transfers because of the smaller overhead; these include HTTP or e-mail attachments. Today, users work with FTP to transfer large files.
To transfer data over the network, there are two transfer modes available; they are ASCII and Binary mode. When you use ASCII mode, you must avoid data corruption, and to do this all data must be in plain text format. When you use Binary mode, the sending machine sends a byte stream for each file, one byte for byte, and the recipient stores the byte stream as it receives it.
The FTP connection involves 2 ports, 20 and 21. Port 20 is the control connection, which is used to open and keep open a connection between the client (which wants the data) and the server (which has the data). Port 21 is the data connection, which receives the data file from the server. Logons can take place using anonymous FTP. This means that when logging on to a server, the account is Anonymous, and one doesn’t need a username or password.
How HTTP File Transfers Work
You can use HTTP to transfer files from a web server into a browser window to view a web page that is on the Internet. You transport files with HTTP only from the server onto the workstation’s browser. But here is the important part: The transferred files are not downloaded onto a computer, so they are not copied into the memory of the workstation. Even with more sophisticated settings available with the Internet, HTTP is not the preferred way to transfer large files.
Examples of FIle Transfer Software
Improvement to the FTP now allow users to work with other formats than just FTP. Here is a short list of some of these programs.
Core FTP
This program allows users to connect in a secure way to an FTP site and download their files. Using an explorer-like interface, the user can see what files are available to download and then select them.
You Send It
For an annual fee of $49.95, you can send files up to 2GB in size.
Global Scape
This product allows HTTP transfers using most browsers. and different operating systems, like Linux, Mac, and Windows.
