What Is Ftp And How It Works

Writen by Vladimir Ghetau

FTP is a method to manage files over the Internet or a network: meet the File Transfer Protocol!

People are generally using the FTP for transfering the files uploaded on their web hosting server. We already talking about files... trasfer, and most important... protocols.

A protocol is a method which informs your computer about the connection to a server or client (in a nut shell, tells the browser how to get the file, how to read the informations about it, etc).

The FTP is a common process used in file trasfers from one computer to another: one computer is the server and the other one is being called - the client (because it connects to the server).

A server is uploading when sending files, and the client is downloading them. These are commonly used terms and I believe you have heard about them before.

To access a FTP server you need an internet or network connection, a FTP address, a username and a password.

The FTP address of the server is the main thing you must know before accessing a server. Here is an example: a friend of mine put some files on his computer and gave me the adress which looks like this: ftp.myfriendsdomain.com

To access this address, i can use my browser (e.g. Firefox, Internet Explorer, etc), or a FTP Client (a software for connecting to FTP servers).

It's possible the server to be password protected, or I will connect anonymously using my email address as a password.

Connecting anonymously?

That's right! If the server is granting acess to everybody, you will connect anonymously - using anonymous word as username and your email address as password. But this happens only when you are allowed to connect anonymously.

In many cases privacy is king. For this reason, the anonymous connection mode is disabled. You will need a username and password to establish a connection to that server. The method is used for protecting different areas on the server.

Clients and browsers?

There is a big difference from connecting to a FTP server using a browser or a client. In most cases the browser will allow to connect and download files from a server.

On the other hand, if you are using a FTP client you can: download, upload, delete files, etc.

FTP vs. HTTP

Accessing a server using the HTTP (Hyper Text Trasfer Protocol) is commonly used for websites. If you will access cnn.com with your browser, you got yourself a quick HTTP connection.

Let me show you two major differences between FTP and HTTP:

1) When connecting to a FTP server you are using a FILE server (that means you can't see anything but files there), but if you connect to a HTTP server you access a WEB server, which means you can load web pages into a browser.

2) Using a FTP connection you can download and upload files to the server, but when you use the HTTP connection you can only download content from the Internet for viewing, is a "read only" method.

Another thing you can do with the FTP method is to change mode of the files. Why? Because you might use certain files that need different permissions.

For example I have a small web application which stores your name and email address inside a file on the server. If that file is write protected, I can't store any information. I need to change it's writing permission. This step is also called chmod-ing a file.

What is CHMOD?

The chmod command is used to change permissions of a file using the File Trasfer Protocol.

After you've uploaded something on a server you might want to set up the file permissions. For example: the owner can change the file's content, but any visitor comming here can only read it.

This is done using 3 simple commands: write, read, execute.

Every command can be assigned (in the same time or dispersed) for owner, groups and anyone else.

Sometimes the chmod commands are hard to use and understand, but now it's easier, thanks to the three digit numbers!

Here are the most used commands for chmod-ing a file:

- CHMOD 644 The file can be read by: owner, groups and everyone else, but can't be changed, or executed but other people excepting the owner.
- CHMOD 700 The file can be read, written and excuted by the owner (user). The groups and everyone else can't read, write or execute it.
- CHMOD 755 The owner, the group and everyone else can read and execute the file, but only the owner can write it. (this is a very common option for chmoding a file because allows the execution of a file - it's valuable for web applications).
- CHMOD 777 Full access to everyone for reading, executing or writing the data.

Fact: FTP is used mostly for uploading files to a web hosting server! Webmasters are using this procedure to put websites online for their visitors.

Free FTP Clients (some of them are free only for personal use):

* http://www.ipswitch.com/ - WS_FTP
* http://www.primasoft.com/ftp.htm - AutoFTP
* http://www.ftpx.com/ - FTP Explorer
* http://www.corbanware.com/ftpworks.html - FTP Works

Best Regards!
Vladimir Ghetau

About the author: Vladimir Ghetau is specialized in professional Web Designing. He wrote the book "How To Advertise Your Business Like A PRO" which helps improving your web site traffic up to 378%. You can see work results on his web design and development website http://www.PixelTomorrow.com/