Downloading and Uploading Files

Browsers are designed to download html files (file types identified by the extension htm or html)' Html is built to format text with tags and activate commands to find other files by using hypertext links.The browser uses HTTP - hypertext transfer protocol to give a command to the server to find a file when you click on the linked text (hypertext). The browser uses TCP/IP layer - Transmission Control Protocol/Internet Protocol - to send the command to the server. The browser receives the file and then opens and displays it in the browser's window.

You can also download files using your browsers built-in FTP capability by going to server directly by typing in a IP address.

You can find and download a true FTP software program in this manner. However, the browser can't handle other tasks well such as:

• all downloading tasks such as large files
• nor can it handle uploading tasks, a function you will perform often when building and maintaining a website
• nor can it handle file and directory management tasks.

This is not the same as FTP (file transfer protocol), which uses a different sending and receiving protocol for uploading and downloading files without opening them or viewing them. It also allows you to view and manipulate files on both the client machine and the server. It is a remote file management system.

What are FTP Clients? - FTP clients are applets or software programs that allow file transfer from one computer to another. There are two general types:

• FTP Software - full functions and features
• Bundled - limited functions and features

FTP clients are similar to e-mail clients in the fact that they can either be bundled with a web browser or they can be a stand-alone program. And, also like e-mail clients, the FTP clients bundled with web browsers are sufficient for most downloading needs, but stand-alone FTP clients usually offer more features.

The main function of FTP clients, however, whether they are bundled or are a separate program, is to transfer files to and from computers connected to the internet.

FTP is a network protocol. It also refers to the method by which we transfer data and program files between computers on the Internet. We refer to computers configured to accept FTP requests as FTP servers. These servers store a tremendous amount of information, and it is available to anyone on the Internet using FTP.

A common way and perhaps the easiest and simplest way to transfer files from one desktop computer to another was via the "sneaker net" - walking a diskette between machines.

Transferring Files can be done by:

• sneaker net via portable storage devices (give examples)
• The Internet via modem or DSL using telephone lines, satellite and other ethernet connections
• Lan via ethernet connections and cable
• serial connection via cable between machines

For Windows machines we use WS_FTP or Core FTP. For Mac's we use a program called Fetch or RBrowser.

Core FTP - http://www.coreftp.com/

WS FTP - http://www.wsftp.com/Products/WS_FTP/home/index.html

RBrowser for Mac - http://www.rbrowser.com/ | download page

Each FTP program has its own interface, some more intuitive and user-friendly than others. After starting, the first thing they require is an FTP server with which the file transfer is to occur. The IP address or domain name identify the server to the program. Depending on the server, it might also require a user identification code and password. Some programs can store a list of regular or favorite servers, including the user identification code and password required for server access.

After the user enters a specific FTP server name or address, the FTP program attempts to connect to the server. Until the program establishes a connection with the FTP server, file transfers cannot take place. When the connection is successful, the FTP program displays its main file transfer screen.

Directories and Files

Most FTP servers run under the UNIX operating system. UNIX uses hierarchical file storage similar to both PC and Macintosh computers.

Directories can hold both files and subdirectories. Accessing a specific file involves knowing all of the directories in the path from the top or root directory down to the file.

To receive a file from an FTP server, we need:

• the server's IP address or domain name,
• the name of the directory in which the file is located,
• the name of the file itself.

The server address is text that can be typed into either:

• a browser window or
• followed as paths using the specific FTP client software such as Core, Fetch or WS_FTP.

The examples below specify all of the necessary information for a user to find a file on an FTP server: the server's name (ftp.csra.net), the directory path (/pub/win3), and the filename (ws_ftp.zip).

Using the domain name: ftp.csra.net/pub/win3/ws_ftp.zip

Using the IP Address: 204.71.8.21/pub/win3/ws_ftp.zip

What is an FTP address? Files on FTP servers have URLs just the same way that web pages do. These FTP addresses function in exactly the same way, and that is to let users find particular files on servers connected to the internet. Here is what an FTP address looks like: ftp://www.netscape.com/public/browsers/communicator.hqx Notice that it looks almost identical to a web address. In fact, the only practical difference is the first three letters. Here is what an FTP address means: ftp:// indicates that the file you are searching for is an FTP file. bullet www.netscape.com indicates the domain name of the server where the file is located. bullet /public/browsers/ indicates the path to the directory where the particular file you are looking for is located. bullet communicator.hqx is the actual file that you are going to download. Notice that the suffix for the file is .hqx instead of .html. This indicates the file is not a web page but a software program, in this case a Macintosh program that has been compressed with BinHex encoding. source: http://avconline.avc.edu/avcoll/ftpwhat.html

 

Common FTP-related directory names include pub, mirrors, uploads, and incoming. The most commonly used directory for files on an FTP server is the pub directory. Under it are stored the many subdirectories and files for public use.

For this class, we will use a FTP client called CORE, the HTML server called webhawks, and a directory for your files called public_html.

We will upload our website files to the server and be able to view them through any browser connected to the Internet, anywhere.In other words, your website will be published on the Internet...but almost no one will know it is there or what the URL is to view it because the world hasn't heard about it.

Class Demo

These instructions will help you configure and use a campus computer or any computer that has CORE installed on it.to upload your website plan files.

Site Name = webhawks

Host/IP/URL = webhawks.org

User Name = bus89 + first 2 letters of first +first 4 letters of last name + last 4 digits of your student ID#:
for example bus189daambr1234 for me.

Password = your birthday in the form of MMDDYY (110750)

Check Box = ssh

Remote Folder = public_html

URL = http://webhawks/~bus189daambr1234

For a more detailed lesson see,

The Internet and FTP - An Introductory Lesson
By Tim McLellan

original lesson

local lesson