Hostname: naic.nasa.gov
Directory path: files/general_info
Filename: resource-discovery-tools.txt
Updated:  July 14, 1993


INTERNET RESOURCE DISCOVERY TOOLS

Recently, several new tools have been designed to help you find
resources on the Internet.  Because the tools are very new, many
people have questions about what the tools do and how they differ from
one another.  This information sheet provides answers to some common
questions.

A good introduction to these tools and a few others can be found in
the "Guide to Network Resource Tools" compiled by the EARN
Association.  The NAIC makes this guide available for file transfer on
the host naic.nasa.gov in the files/general_info directory as
earn-resource-tool-guide.txt (ASCII version) and
earn-resource-tool-guide.ps (PostScript version).  The guide provides
pointers to client versions of the software and to mailing lists for
learning more.

WORLD-WIDE WEB


The World-Wide Web (WWW or W3) is a system designed to tie together
all the information available on the Internet into one seamless web of
information.  That may seem like an overly ambitious challenge, but
the results so far have been amazingly successful.  WWW is a hypertext
information retrieval system.  In practical terms, this means that you
can follow your own path through the complex web of Internet
information and services without having to know beforehand where
things are located.  World-Wide Web links all the other resource
discovery tools discussed here and, by so doing, presents one
consistent interface to the network user, even when he is using
different programs on different hosts.  You may have seen the NAIC
demonstrating a WWW client called NCSA Xmosaic.  WWW clients for
several platforms are now under development; once these are generally
robust and available, the NAIC plans to offer support of this service
to NASA Internet users.

GOPHER

The Internet Gopher delivers a wide variety of diverse types of
information in an easily used menu-driven interface.  Gopher servers
seamlessly link information from all around the Internet in a manner
that can be transparent to the user. (Users can easily discover the
source of any piece of information, however, if they wish.)  For
example, Gopher links many different databases, applications, white
pages directories, sounds, and pictures.  The NAIC gopher is
accessible via telnet when you log in to the host naic.nasa.gov as
"naic".

VERONICA

The success of the Gopher means that there are hundreds of Gophers
available all over the world, all linked.  While one can step
through all these menus and discover information far more easily
than was ever previously possible on the Internet, the number of
Gopher servers precludes the most direct access to information.
Veronica is a service that was created to help you find Gopher
information without having to do a menu-by-menu, site-by-site
search.  The Veronica service, itself accessible from within
'Gopherspace," is a searchable index of Gopher menu items.  If
you give Veronica a word (or words), it will search its index of
Gopher menu titles and present its findings in a special menu that
you can step through as you would any other Gopher menu.

ARCHIE

Archie was one of the first resource discovery tools (and the
inspiration for "Veronica," which comic book readers will
appreciate).  Archie is best known as a resource that polls hosts
offering files for anonymous FTP and creates a database of file
names.  (Anonymous FTP is a means by which certain archive sites
allow general access to their files. A user may FTP to the site and
log in as anonymous, using the word guest or the users
electronic mail address as a password.)  Archie polls more than
1,000 such anonymous FTP sites; the Archie database contains more
than 2 million file names.  You can search the Archie database,
which is currently available at 15 locations, to find pointers to
files of interest to you.  You can access the database via interactive
Telnet session, by email, or by implementing an Archie client on
your local host.

WAIS

WAIS (pronounced "ways") stands for Wide Area Information Server
and is, not surprisingly, a distributed information retrieval
system.  It provides a natural language system that you can use to
search databases all over the Internet.  With WAIS, although you are
searching data in different systems, you don't have to learn
different query languages for each database.  So far, WAIS is
primarily used to find textual information; however, the service need
not be limited to text resources.  To use WAIS, you specify what
terms you want to search for and which sites you want to search (an
index of all the sites is available), and it will do the search and
provide the results.  Some sites offer a local WAIS database, but do
not connect to other WAIS servers.

LEARNING MORE

If you'd like to learn more about these information services,
there are several sources online and in text that can help you.
Here are two good places to start:

   EARN Association. Guide to Network Resource Tools .  1993 May 3.
   63 p.  FTP from host naic.nasa.gov as
     /files/general_info/earn-resource-tool-guide.txt or
     /file/general_info/earn-resource-tool-guide.ps.

   Krol, Ed.  The Whole Internet User's Guide and Catalog.  1992,
   Sebastopol, CA: O'Reilly & Associates, Inc.  376 p.

Or log in to NAIC's gopher and explore:

CONNECTING TO THE NAIC GOPHER

The NAIC runs a Gopher server that is linked to all the other Gophers
known to the "root" Gopher.  You can access the NAIC Gopher
(and hence all others) by connecting to the host naic.nasa.gov.
Once logged in as naic you will automatically be placed at the top
menu of our Gopher, from which you can choose the "Searching
Gopherspace with veronica" item.

Connecting from an Internet host:
   telnet naic.nasa.gov
   [login:] naic

Connecting from a VMS host:
   SET HOST EAST
   [login:] naic.nasa.gov!
   [login:] naic

NEED HELP?

Do you have any questions about
   these tools or documentation describing them?
   transferring files?
   discovering Internet resources?
   services offered by the NAIC?

If so, contact the NAIC:

NASA Network Applications and Information Center (NAIC)
NASA Ames Research Center
M/S 233-18
Moffett Field, CA 94035-1000

Telephone: +1-800-858-9947 or +1-415-604-0600
FAX:       +1-415-604-7300
Email from an Internet host:  naic@nasa.gov
Email from a DECNET host:     EAST::"naic@nasa.gov"
