FTP Introduction (WS_FTP)
File Transfer Protocol, or FTP,
allows you to move files from computers on the Internet
to your own machine and vice versa. FTP service is generally setup on an Internet server,
and is not part of the World Wide Web. Historically, a Web browser can be used to access files
on an FTP server by specifying ftp as the protocol of the URL. Some information on the Web
is available only on FTP sites,
so it is good to develop proficiency in finding and downloading using this protocol.
Fortunately the major search engines catalog ftp sites and normally there is an <1>http://
alternative available that will appear as a search result.
To illustrate some more good FTP sites, check out ftp://ftp.cdrom.com
for a variety of file types, and you will find high quality astronomical photos from nasa at
ftp://skyview.gsfc.nasa.gov/pub/.
Other sites available at universities and public ftp servers will provide downloads of--
- Mind-blowing raytraced pictures
- Awesome animation files
- Unbelievable graphics/sound demonstrations
- Recent shareware games
- Excellent music files, some even available legally from the artist before they are published
- Text of bills pending or passed in the US Congress
To login to one of these "public" servers, you will use what is called
anonymous FTP. By using anonymous as your login at the remote site, you will be
telling the host computer that you wish to access the publicly available materials that
the system administrator has placed on that machine. You can use your e-mail address as
your password to complete the login process. Once logged in, you will move about in the
remote computer's directories to find the file you want and start the download process.
Newer browsers such as Netscape Navigator or Microsoft Internet Explorer
allow access to the ftp protool directly. Within Microsoft Windows Explorer file manager,
you also may specify an ftp address and the operating system will look for the resource using
your Internet connection.
Looking at these public sites, you will sometimes find the contents listed using the
crypic UNIX style. You may need to list directories with the command
ls -lastr
This command will list the current directory. If you were to just type "ls"
by itself, it would just give you the names of files and directories in a brief
listing. It is quicker, but it doesn't give you very much information. If you use the
complete "ls -lastr", it lists ALL files and directories, including
hidden files, gives information on each file and directory, and lists them so that the
most recent files and directories are listed last.
Usually, the first directory listing that you see on FTP sites is really messed up--it
has directories that you would never want to explore. The directory that you will almost
always want to change to first is the /pub directory, which stands for
"public". This is usually where all the good stuff is located. To do this, use
the "change directory" command:
cd pub
Then, you can type ls -lastr again to see the files in the pub directory. Let's say you
find a directory in the pub directory called "games" and you want to
check it out. You would then type:
cd games
ls -lastr
to change to the games directory and list it. Remember to double click files for
download.
Using the SLIP/PPP account of an ISP connection, you can perform
FTP operation in a graphical environment, using any of a number of different client
programs. One of the most popular of these, called WS_FTP (Windows Socket File Transfer
Protocol), is shown in this illustration. Created by John Junod and Ipswitch, Inc.,
WS_FTP makes transferring files easy. The left pane of the graphical presentation shwos
the contents of your computer, and the right pane shows the contents of the connected
computer. The program is available in both a professional edition called WS_FTP PRO and a
freeware version called WS_FTP LE. This is certainly one of the easiest ways to manage
files between your computer and the Internet.
WS_FTP can be downloaded from http://www.shareware.com.
Logging On - When WS_FTP is started, you first need to establish a link to the
server site. The numbers on these instructions correspond to the picture below.
- New - Assuming this is your first time logging onto your website, click on
"new."
- Profile Name - Something you'll remember in the future. The name of your business
works well here.
- Host Name - Your FTP address is the form: ftp.your-domain.com or perhaps an IP
address such as 198.189.62.35
- Host Type - Set to: Automatic Detect.
- User ID - Enter the user ID you were assigned when your account was first set up.
- Password - Enter the password you were assigned when your account was first set
up. Not necessary for anonymous FTP, but e-mail address is normally used.
- Annonymous Login - Leave this box UNchecked when using a secure FTP
account.
- Save Password - Checking this box will allow you to log in anytime in the future
without re-entering your password. Do not check this if you have security concerns or if
you share your computer with others.
- Save - Clicking "Save" will add this to the dropdown list in #1. It
will also save all the information previously entered in this profile.
- OK - Click here to log on!
Uploading Files - The numbers on these descriptions correspond to the picture
below them.
- Local System - Gives you the directory location of the local (your computer)
system.
- Remote System - Gives you the directory location of the remote (Internet) system.
- Local File & Directory List - Lists all files and directores on the local
system.
- Remote & Directory List - Lists all files and directores on the remote
system.
- Local Control Buttons - Commands refer to files and directories on the local
system.
- Remote Control Buttons - Commands refer to files and directories on the remote
system.
- Begin File Transfer - Top button (arrow left) downloads, bottom button (arrow
right) uploads.
- ASCII Mode - Select this mode to transfer all your .html, .txt and .cgi files.
- Binary Mode - Use this mode for all your images, multimedia files, and programs
you wish to make available for others to download.
When
you first start WS_FTP, you will be presented with this screen (you can also reach it by
clicking on the Connect button on the primary WS_FTP screen). The Session Profile dialog
box is what you will use to specify the FTP site to which you want to connect. Notice that
WS_FTP provides a check box for anonymous FTP; when this is checked, the program
automatically inserts anonymous as your login.
If you know the host name or IP number of the FTP site you want to access, you can type
it directly into the "Host Name" box. If you're just learning about FTP, you
probably don't have any addresses in mind. However, the addresses for a number of popular
FTP sites are included in WS_FTP. You can see a list of these pre-programmed sites by
clicking on the down-arrow to the right of "Profile Name" at the top of the
window.
WS_FTP
now shows a list of several popular FTP sites. In general, they fall into two categories.
Archival sites maintain massive collections of software for most kinds of computers. The
OAK Archives are an example. Other sites on this list have been chosen because they
contain popular client programs for using the Internet. By using just these sites, you can
build up a complete collection of network software.
Let's take a look at one of these sites. You're going to travel the home of WS_FTP. The
first step is to highlight the WS_FTP entry on the Session Profile screen by clicking on
it once. Notice that the highlight bar is on this site in the above figure. To make the
actual connection to the site, click on the OK button.
When
you connect to a site, the main WS_FTP window, previously in the background, will now
become active. The main WS_FTP screen is divided into three sections: local file
information (on your computer) on the left, remote file information (on the FTP site) on
the right, and a status box (containing details about the FTP session) at the bottom.
The status box reports messages related to the program's attempt to connect. When
running your own copy of the program, you will be able to scroll through the text with the
up- and down-arrow to the right of the box.
The local and remote file information areas have similar layouts. Both display the
current directory at the top, a list of directories and/or drives below the current
directory, and a list of files in the current directory at the bottom. Next to each
section is a group of buttons you can use to navigate through the directories and
manipulate the files.
Once you are connected to a site, you will see a directory listed in the box at the top
of the "Remote System" side, and a number of directories and files in their
boxes. You can select a file or directory simply by clicking on the name.
Now that you have selected a file, you'll notice that several more options for manipulating
files have become available. The buttons are no longer grayed out, indicating you can
select them. Note, however, that you will not have permission to rename or delete files on
most ftp sites.Only authorized users and system administrators at the sites are able to
use these commands.
The buttons between the local and remote areas are for copying files from one side to
the other. For example, the left-arrow downloads the selected file, i.e., copies it from
the right to the left.
NOTE: You should keep an eye on the transfer mode settings above the status box; they
appear as selectable buttons marked ASCII and Binary. When downloading text files (like
README files and directory indices), you can be in ASCII mode. When downloading binary
files (such as compressed files, executables, data or other archived material), you should
check that you are in Binary mode. If you download a binary file in ASCII mode, the file
will be corrupt and you will need to download it again.
Because there are no significant problems with downloading an ASCII file in Binary
mode, you should probably stick with Binary until you are familiar with FTP procedures.
WS_FTP defaults to Binary mode, so this is less of a concern than with older FTP programs.
To download a file, make sure the file you want is highlighted and click on the
left-arrow.
Now
the actual transfer starts. When you transfer a file, you will see a Transfer Status box.
The box indicates the percentage of the file that has been transferred at any given
moment, the speed, and the number of bytes. The times to the right of Kbps (file size)
indicate the time elapsed and time remaining in the transfer.
The speed of the file transfer depends upon a number of factors, perhaps the most
important of which is the speed of your network connection. If you are using a high-speed
modem at 56.6 Kbps, your rates will be the highest possible over the copper wire
connection that services most homes and many businesses. If you work with a dedicated
network connection at your office, transfer rates may be higher, depending upon the type
of connection you use.
The SLIP/PPP connection illustrated with WS_FTP allows file transfers to proceed
directly to your machine. With a shell account, you would be required to transfer the file
first to your service provider's computer and only then to your own. This is one of the
many reasons that SLIP/PPP is gaining in popularity, especially as the price of an account
has dropped.
When the file transfer is complete, the Transfer Status box will close and return you
to the main WS_FTP window.
After the file has been downloaded, you will see it in the box on the left, in the local
file area. This indicates the file is now present on your computer. You'll also note that
WS_FTP maintains a log of transferred files, called ws_ftp.log, which will appear
automatically in this space. Each file you transfer with WS_FTP uses these same
techniques.
You can also choose to view a text file on-screen by highlighting it and clicking on
the View button. In general, this method is recommended only for very short text files.
Your connection to an FTP site is one of many that may be in progress, and there is no
sense in tying up the site while you read materials that could better be read by
downloading them.
When you are finished with an FTP site, you can click the "Close" button at
the bottom left to close the FTP session.
Once you have closed your ftp session, you can open another session or exit WS_FTP.
As you can see, using a graphical program like this one makes the FTP process a much
simpler procedure. There is no need to memorize and enter complicated commands, as is
required with a shell account. But bear in mind that, no matter which method you use to
access remote files, the underlying protocols remain the same. Whether you're running your
session through a shell account or through SLIP/PPP, you are still sending commands that
are managed by the underlying TCP/IP system. What differs is what you see on the screen,
and the fact that with a SLIP/PPP connection, the file comes directly to you.
WS_FTP is my choice of the FTP clients for Microsoft Windows, and I recommend that you
get a copy of it. Although a Web browser can be used to handle FTP sessions, more
specialized programs like WS_FTP handle the details better and offer a wider range of
options. Think of WS_FTP as part of an Internet toolbox that you will use for your network
chores. You'll keep building that toolbox as new software is released and older programs
are updated. Other popular shareware FTP programs for the PC is CuteFTP ; Dartmouth
College created Fetch for the Mac.
You may wish to download a copy of WS_FTP to your computer, or CuteFTP or Fetch. Once
you select a version of FTP to download, your browser will probably display a file
selection window. Choose a directory on your computer to which you want to download the
program. You'll then be able to click on the OK button to begin the download.
WS_FTP and other on-line downloadable programs are often distributed in a compressed
ZIP archive. If you do not have an unzipping program, click on WinZip to download a Windows-based archive utility (another
essential tool). After completing the download, run the executable (double click) to
extract the program. You might want to create a separate directory in which to run the
self-extracting program, because it creates a number of files.
FTP Searches
The Internet contains millions of files that you may download to your computer. Some
are available as links on the Web, while others are available using a connection to an FTP
server (check out ftp://ftp.cdrom.com). To find such files, you need
to search specifically for FTP content from your search engine of choice (maybe search
with ftp and keywords together), or may use some search tools designed
specificaly for FTP searches. The
Library of Congress site contains a great list of public ftp servers.
Archie
Archie (kind of reminds you of archive) is a search tool for FTP searches on the
Internet. Archie searches its own archive, which is compiled from the millions of files
that are available on anonymous FTP sites. Begin with this index to some interesting Archie resources.
FILEZ
Many commercial files on the Internet are not indexed by Archie. 
is a
commercial file search site
that allows searches by name, highlights files of the day, and provides a list of files
added within the past 20 days.