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Telnet,
FTP, and Gopher
Chapter Eight |
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Telnet
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Allows log-in access to another computer on the
Internet |
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FTP
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File Transfer Protocol. Copy (transfer)
a file from one site on the Internet to another |
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Gopher
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Gives access to services and information on the
Internet through text-only menus |
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These protocols can be used with a Web browser. You can tell the protocol
being used by looking at the URL for a resource. You would use the URL http://lcweb.loc.gov,
for example, to go to the home page for the Library of Congress. The protocol
here is http. The Library of Congress also provides access to its resources
through:
| Telnet |
Use the URL telnet://locis.loc.gov
to connect to a remote computer and search the Library's holdings.
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| FTP |
Use the URL ftp://lcweb.loc.gov
to copy files without viewing them first |
| Gopher |
Use the URL gopher://lcweb.loc.gov
for a menu oriented (little text and no images) interface to basically
the same information available as a Web page |
Telnet
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Examples of resources available through Telnet |
Library of Congress telnet://locis.loc.gov
Search for materials available at the United States Library
of Congress. No log in name or password is required.
PEN pages telnet://world@psupen.psu.edu
. Search and retrieve information from agricultural, health,
teaching, and other databases. This service is provided by the College
of Agriculture of the Pennsylvania State University and the Pennsylvania
Department of Education. You type in the word world when
you see the prompt Username:
Weather Forecasts telnet://madlab.sprl.umich.edu:3000
Check weather forecasts and other weather related information.
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| Using
Telnet With Your Browser |
Version 4 of Netscape Navigator is preset to use the
Telnet program that's included with the Windows 95 or Windows 98 operating
system.
When you type a Telnet URL, such as telnet://locis.loc.gov, in
the location field, then the Telnet program is automatically activated
to start a Telnet session.
If you don't have a Telnet program on your computer then
- Find a location on the Internet that has Telnet programs
to fit into your environment. A collection of programs that work
well is available at the
Terminals and Telnet section of
Winfiles.com, a large collection of shareware for Windows
95/98 computer systems. Remember to register, and pay for, the
shareware programs you use. I use NetTerm.
- Retrieve a Telnet program. After giving the URL or clicking
on a hyperlink, you might get a message "No Viewer Configured
for File Type: application/x-zip-compressed" from Netscape
Navigator. That's because the file is stored in compressed format
using a program named PKZIP or WinZip, and your Web browser doesn't
have those programs installed as "helper" programs to
automatically uncompress the file after it's been transmitted.
That's just fine; select the option that lets you "Save to
Disk." A "Save As.." dialog box pops up for you
to specify the folder to use to store the file. Store the file
in a directory/folder that you'll use for the installation and
may want to remove after the program is installed.
- Uncompress and Install the Telnet program. To uncompress
you'll need a copy of PKZIP
or WINZIP.
Follow the instructions that come with those programs to uncompress
the file you've retrieved. After you uncompress the file, look
for a file with a name similar to "read me" for instructions.
If none is present, click on the file named "setup"
and follow the installation instructions.
Once you have a copy of Telnet on your computer, set the Netscape
preferences for "Applications".
- Click on Edit on the Menu Bar, then Preferences
and select Applications.
- Look for the item URL:Telnet Protocol in the list that appears.
Click on it and then click on Edit
- Type the location, on your computer, of the Telnet program into
the pane as show in this figure.
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| Some
other Web resources about Telnet |
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FTP, file transfer protocol, is one of the
basic Internet services. It's designed to copy files from one computer
system to another. One of the primary reasons for creating the Internet
was so that researchers could exchange ideas and results of their work,
and FTP allows that exchange and sharing information, data, or any sort
of file.
In this section we'll look at using anonymous FTP to retrieve
copies of files from another site on the Internet. The term anonymous
means anyone on the Internet can copy files from a computer system without
being a registered user of that system.
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URL Format for FTP |
The general form of a URL for anonymous FTP is: ftp://name-of-ftp-site/directory-name/file-name
- The URL for anonymous FTP starts with ftp://.
- The name of the FTP site follows the three characters
://.
- The name of the directory starts with the first
single / and goes up to but not including the last /.
- The name of the file follows the last /.
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| Retrieving
a File by Anonymous FTP |
You can retrieve a file, that is copy it from a remote
site to the computer you're using, in one of two ways.
- Typing in a URL (Open a Location).
- Shift and Click on a Hyperlink
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| Example
2 |
Retrieving a File by Anonymous
FTP |
We'll retrieve a file available from NASA that contains
an image of Mars using both methods mentioned above.
First, we type the URL (open the location) ftp://ftp.jpl.nasa.gov/pub/images/browse/mars1.gif
and then select Save As.. from File in the menu bar.
Second, we open the location ftp://ftp.jpl.nasa.gov/pub/images/browse/,
find the hyperlink for the file, and use Shift+Click to retrieve it.
End Example 2
| Working
with compressed an archived files |
Some helpful programs
Collections of programs used for archiving and compression
Tips for dealing with compressed files and archives
- The last few letters of a file name are often the clue that
the file is in compressed form.
- Find someone locally who can help you with compressed files.
- Use anonymous ftp to get copies of these files to read about
the compression formats used.
- Take a look at the Web page
Common Internet File Formats Compiled by Eric Perlman and
Ian Kallen for Internet Literacy Consultants.
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| Example
3 |
Retrieving a Shareware Programs
and a Compression Program |
There are lots of shareware programs available by anonymous
FTP. In this example we'll go to an anonymous FTP site and retrieve a
shareware genealogy program.
We'll assume Netscape Navigator is started and we're working in a Web
Browser Window. The steps to follow are:
- Start an anonymous FTP
session with SUNET's,
the Swedish University Network's, FTP archive.
- Connect to the directory /pub2/pc/mirror/simtelnet/win3/genealgy/.
- Retrieve the genealogy program kk302.zip.
- FTP to uiarchive.cso.uiuc.edu
to retrieve the program WinZip
for Windows 95. Change to the directory at uiarchive.cso.uiuc.edu
holding the archive for WinZip.
- Install WinZip95 and the genealogy program.
End Example 3
Finding Files Available by Anonymous FTP
| FTP
Archives |
- UIArchive
- Washington
University Data Archive
- Garbo
Archives, University of Wasa, Finland
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Anti-Virus Software
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- McAfee,
Network General, PGP & Helix have merged to create a new company,
Network Associates. Welcome to www.nai.com!
- Symantec
AntiVirus research Center
- Data
Fellows World-Wide Web Server Main Index
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Listings of Shareware
Sources
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- Technology:
Software and Downloads
- Nerd's
Heaven: The Software Directory Directory
- Yahoo!
Computers and Internet:Software:Shareware
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Compression Software
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- WinZip
Home Page
- Welcome
to PKWAREŽ Inc.
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Shareware
Archives
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- File
Mine -- Dig Our Downloads of Shareware, Games and Commercial
Demos
- DOWNLOAD.COM
-- Welcome
- SHAREWARE.COM
-- the way to find shareware on the Internet
- ZDNet
Software Library - Download top-rated shareware, freeware, demos
and more
- Welcome
to WinFiles.com! The best 32-bit Shareware, Drivers, Tips, and
Information on the Internet!
- Internet
Software - Download Net Software. Stroud's Consummate Winsock
Apps List (CWSApps)
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FTP Clients for Windows
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A text-based FTP is usually included with computers
that use MS-Windows operating systems. Click on Start, then Run,
type ftp and press enter. You'll have to type a username
and password. Then get to retrieve a file, put to
place a file on a remote system, and quit to end the FTP
session.
WS_FTP by John Junod is relatively easy to use FTP client
with a graphical user interface.
Here's a short list of guides for WS_FTP:
- PC-WSFTP
- Installing
a Winsock FTP Client
- Junod
Software Home Page
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| Archie |
The term Archie is just a shortened form
of the word archive. Archie was designed to effectively deliver
information about items available in FTP archives. (It wasn't
named after the comic book character.) Archie was conceived and
implemented by Alan Emtage, Peter Deutsch, and Bill Heelan of
Mcgill University, Quebec, Canada.
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Like the WWW Gopher puts the focus on the information,
not on learning a number of different techniques. A Gopher server provides
a menu to represent the information and resources it has available. You
work with one or more menus, choosing items that are documents (files),
directories, links to other Internet sites, tools to help you find information,
or other Internet services. You don't have to know many techniques to
use Gopher; most of the time you only need to be able to choose items
from a menu. Eventually, you come to a menu item representing a text document,
image, or other type of file.
Sources of Information About Gopher
What's Available through Gopher?
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