Go to the previous, next chapter.
Telnet is the main Internet protocol for creating a connection with a remote machine. It gives the user the opportunity to be on one computer system and do work on another, which may be across the street or thousands of miles away. Where modems are limited, in the majority, by the quality of telephone lines and a single connection, telnet provides a connection that's error-free and nearly always faster than the latest conventional modems.
As with FTP (see section Anonymous FTP), the actual command for negotiating a telnet
connection varies from system to system. The most common is
telnet itself, though. It takes the form of:
To be safe, we'll use your local system as a working example. By now, you hopefully know your site's domain name. If not, ask or try to figure it out. You'll not get by without it.
To open the connection, type
If the system were
wubba.cs.widener.edu, for example, the
command would look like
The system will respond with something similar to
Trying 18.104.22.1689... Connected to wubba.cs.widener.edu. Escape character is '^]'.
The escape character, in this example ^] (Control-]), is
the character that will let you go back to the local system to close
the connection, suspend it, etc. To close this connection, the user
would type ^], and respond to the
telnet> prompt with the
command close. Local documentation should be checked for
information on specific commands, functions, and escape character that
can be used.
Many telnet clients also include a third option, the port on which the connection should take place. Normally, port 23 is the default telnet port; the user never has to think about it. But sometimes it's desirable to telnet to a different port on a system, where there may be a service available, or to aid in debugging a problem. Using
telnet somewhere.domain port
will connect the user to the given port on the system somewhere.domain. Many libraries use this port method to offer their facilities to the general Internet community; other services are also available. For instance, one would type
telnet martini.eecs.umich.edu 3000
to connect to the geographic server at the University of Michigan (see section Geographic Name Server). Other such port connections follow the same usage.
Over the last several years, most university libraries have switched from a manual (card) catalog system to computerized library catalogs. The automated systems provide users with easily accessible and up-to-date information about the books available in these libraries. This has been further improved upon with the advent of local area networks, dialup modems, and wide area networks. Now many of us can check on our local library's holdings or that of a library halfway around the world!
Many, many institutions of higher learning have made their library catalogs available for searching by anyone on the Internet. They include Boston University, the Colorado Alliance of Research Libraries (CARL), and London University King's College.
To include a listing of some of the existing sites would not only be far too long for this document, it would soon be out of date. Instead, several lists are being maintained and are available either by mail or via FTP. Also, the Internet Resource Guide (IRG) also describes a few libraries that are accessible---see section Internet Resource Guide for further information.
Art St. George and Ron Larsen are maintaining a list of
Internet-accessible libraries and databases often referred to as ``the
St. George directory.'' It began with only library catalogs but has
expanded to include sections on campus-wide information systems, and
even bulletin board systems that are not on the Internet. The library
catalog sections are divided into those that are free, those that
charge, and international (i.e. non-U.S.) catalogs; they are arranged
by state, province, or country within each section. There is also a
section giving dialup information for some of the library catalogs.
It's available for FTP (see section Anonymous FTP) on
in the directory cerfnet/cerfnet_info/library_catalog. The
file internet-catalogs has a date suffix; check for the most
current date. The information is updated periodically.
Billy Barron, Systems Manager at the University of North Texas,
produces a directory as an aid to his user community. It complements
the St. George guide by providing a standard format for all systems
which lists the Internet address, login instructions, the system
vendor, and logoff information. The arrangement is alphabetic by
organization name. It's available for FTP on
vaxb.acs.unt.edu in the subdirectory library as the file
For announcements of new libraries being available and discussion on
related topics, consult the Usenet newsgroup
comp.internet.library (see section Usenet News to learn how to read
Freenets are open-access, free, community computer systems. One such system is the Cleveland Freenet, sponsored by CWRU (Case Western Reserve University). Anyone and everyone is welcome to join and take part in the exciting project---that of a National Telecomputing Public Network, where everyone benefits. There's no charge for the registration process and no charge to use the system.
To register, telnet to any one of
freenet-in-a.cwru.edu freenet-in-b.cwru.edu freenet-in-c.cwru.edu
After you're connected, choose the entry on the menu that signifies you're a guest user. Another menu will follow; select Apply for an account, and you'll be well on your way to being a FreeNet member.
You will need to fill out a form and send it to them through the Postal Service---your login id and password will be created in a few days. At that point you're free to use the system as you wish. They provide multi-user chat, email, Usenet news, and a variety of other things to keep you occupied for hours on end.
There are a few systems that are maintained to provide the Internet community with access to lists of information---users, organizations, etc. They range from fully dedicated computers with access to papers and research results, to a system to find out about the faculty members of a university.
Knowbot is a ``master directory'' that contains email address
information from the NIC WHOIS database (see section The WHOIS Database), the PSI White
Pages Pilot Project, the NYSERNET X.500 database and MCI Mail. Most
of these services are email registries themselves, but Knowbot
provides a very comfortable way to access all of them in one place.
nri.reston.va.us on port 185.
PSI maintains a directory of information on individuals. It will list
the person's name, organization, and email address if it is given.
wp.psi.net and log in as fred. The White
Pages Project also includes an interface to use Xwindows remotely.
For information on database services, see section Commercial Databases. Not all databases on the Internet require payment for use, though. There do exist some, largely research-driven databases, which are publicly accessible. New ones spring up regularly.
To find out more about the databases in this section, contact the people directly responsible for them. Their areas of concentration and the software used to implement them are widely disparate, and are probably beyond the author's expertise. Also, don't forget to check with your local library---the reference librarian there can provide information on conventional resources, and possibly even those available over the Internet (they are becoming more common).
The Colorado Alliance of Research Libraries (CARL), in association
with CARL Systems Inc., operates a public access catalog of services.
Offered are a number of library databases, including searches for
government periodicals, book reviews, indices for current articles,
and access to to other library databases around the country. Other
services are available to CARL members including an online
encyclopedia. Telnet to
pac.carl.org, or write to
email@example.com for more details.
PENpages is an agriculturally-oriented database administered by
Pennsylvania State University. Information entered into PENpages is
provided by numerous sources including the Pennsylvania Dept. of
Agriculture, Rutgers University, and Penn State. Easy-to-use menus
guide users to information ranging from cattle and agricultural prices
to current weather information, from health information to
agricultural news from around the nation. A keyword search option
also allows users to search the database for related information and
articles. The database is updated daily, and a listing of most recent
additions is displayed after login. Telnet to
and log in as the user PNOTPA.
Clemson maintains a database similar to PENpages in content, but the
information provided tends to be localized to the Southeastern United
States. A menu-driven database offers queries involving the weather,
food, family, and human resources. Telnet to
eureka.clemson.edu and log in as PUBLIC. You need to be
on a good VT100 emulator (or a real VT terminal).
The Computer Science department of the University of Maryland
maintains a repository of information on a wide variety of topics.
They wish to give a working example of how network technology can (and
should) provide as much information as possible to those who use it.
info.umd.edu and log in as info. The
information contained in the database is accessible through a
screen-oriented interface, and everything therein is available via
There is a mailing list used to discuss the UMD Info Database,
welcoming suggestions for new information, comments on the interface
the system provides, and other related topics. Send mail to
firstname.lastname@example.org with a body of
subscribe INFO-L Your Full Name
See section Listservs for more information on using the Listserv system.
The University of Michigan's Department of Atmospheric, Oceanic, &
Space Sciences maintains a database of weather and related information
for the United States and Canada. Available are current weather
conditions and forecasts for cities in the U.S., a national weather
summary, ski conditions, earthquake and hurricane updates, and a
listing of severe weather conditions. Telnet to
madlab.sprl.umich.edu on port 3000 to use the system.
A geographic database listing information for cities in the United States and some international locations is maintained by Merit, Inc. The database is searchable by city name, zip code, etc. It will respond with a lot of information: the area code, elevation, time zone, and longitude and latitude are included. For example, a query of 19013 yields
0 Chester 1 42045 Delaware 2 PA Pennsylvania 3 US United States F 45 Populated place L 39 50 58 N 75 21 22 W P 45794 E 22 Z 19013 Z 19014 Z 19015 Z 19016 .
To use the server, telnet to
martini.eecs.umich.edu on port
3000. The command help will yield further instructions, along
with an explanation for each of the fields in a reponse.
FEDIX is an on-line information service that links the higher education community and the federal government to facilitate research, education, and services. The system provides accurate and timely federal agency information to colleges, universities, and other research organizations. There are no registration fees and no access charges for FEDIX whatsoever.
FEDIX offers the Minority On-Line Information Service (MOLIS), a database listing current information about Black and Hispanic colleges and universities.
Daily information updates are made on federal education and research
programs, scholarships, fellowships, and grants, available used
research equipment, and general information about FEDIX itself. To
access the database, telnet to
fedix.fie.com and log in as
The STIS is maintained by the National Science Foundation (NSF), and
provides access to many NSF publications. The full text of
publications can be searched online and copied from the system, which
can accommodate up to ten users at one time. Telnet to
stis.nsf.gov and log in as public. Everything on the
system is also available via anonymous FTP. For further information,
STIS, Office of Information Systems, Room 401 National Science Foundation 1800 G. Street, N.W. Washington, D.C. 20550
email@example.com(202) 357-7492 (202) 357-7663 (Fax)
The University of Delaware College of Marine Studies offers access to
an interactive database of research information covering all aspects
of marine studies, nicknamed OCEANIC. This includes the World Oceanic
Circulation Experiment (WOCE) information and program information,
research ship schedules and information, and a Who's Who of email and
mailing addresses for oceanic studies. Data from a variety of
academic institutions based on research studies is also available.
delocn.udel.edu and log in as INFO.
The NASA/IPAC Extragalactic Database (NED) is an ongoing project,
funded by NASA, to make data and literature on extragalactic objects
available over computer networks. NED is an object-oriented database
which contains extensive information for nearly 132,000 extragalactic
objects taken from about major catalogs of galaxies, quasars, infrared
and radio sources. NED provides positions, names, and other basic
data (e.g. magnitude types, sizes and redshifts as well as
bibliographic references and abstracts). Searches can be done by
name, around a name, and on an astronomical position. NED contains a
tutorial which guides the user through the retrieval process. Telnet
ipac.caltech.edu and log in as ned.
Operated by the U.S. Naval Observatory in Washington, D.C., this
automated data service provides database access to information ranging
from current navigational satellite positioning, astronomical data,
and software utilities. A wide variety of databases can be searched
and instructions for file transfer are given. Telnet to
tycho.usno.navy.mil and log in as ads.
@vskip 0pt plus 1filll @flushright ``My consciousness suddenly switched locations, for the first time in my life, from the vicinity of my head and body to a point about twenty feet away from where I normally see the world.'' Howard Rheingold, Virtual Reality @end flushright