Source: Telecommunications, April 1993 v27 n4 p33(1).
Title: On the trail of the Internet Gopher. (Technical Update)
(Technical)
Author: Mark P. McCahill
Abstract: The Internet Gopher is a protocol that facilitates creating
distributed information systems and arranging access on local networks as well
as on the Internet. Gopher makes it easy to navigate on the Internet, allowing
non-technical users to find and access various sorts of resources. Internet
Gopher client software provides users with a virtual information matrix, or
'gopherspace,' so that users can browse through hierarchical menus, or
alternatively, search by submitting queries to full-text search engines. There
were more than 500 Gopher servers on the Internet as of Dec 1992, and more
than one million items were available via these servers. Gopher software is
available for anonymous ftp from boombox.micro.umn.edu in the pub/gopher
directory. Versions are available for various platforms including Apple
Macintosh, PC, NeXT, X Windows, VMS, VM/CMS and VT-100 terminals. The
University of Nevada has developed a service called VERONICA (very easy
rodent-oriented net-wide index to computerized archives), which is a
searchable index of items on gopher servers.
Subjects: Computer networks - Services
Products: Internet - Services
Business Collection: 70Z0638
Electronic Collection: A13749204
RN: A13749204
Full Text COPYRIGHT Horizon House Publications Inc. 1993
Internet Gopher is a simple protocol for building distributed information
systems and organizing access to resources on local networks as well as on the
Internet. Gopher is designed to make navigating the Internet and accessing
distributed resources easy for novice and non-technical users. Because novice
users access information in different ways (by browsing or by submitting
search requests), Gopher combines seamless browsing across multiple servers
and full-text searching functions.
The Internet Gopher client software presents users with a virtual information
matrix (gopherspace) that they can navigate by browsing a hierarchical
arrangement of items, or search by submitting queries to full-text search
engines. For browsing in gopherspace, the gopher client software presents the
user with lists of items from which the user selects an item of interest,
typically by pointing and clicking with a mouse. For instance, at the
University of Minnesota, a user might find a salmon recipe by looking in the
fun and games directory for the recipes directory that contains a seafood
directory.
Alternatively, the user can select an option called "search lots of places" at
the University of Minnesota. When this search option is selected, the user is
prompted by the gopher client software for a key word (salmon) and a full-text
search is done by the server. The result of the search is a list of items that
matches the search criteria.
While searching for recipes is fun, Internet Gopher has serious applications:
at the University of Minnesota it is possible to search through a technical
information Q&A data base of over 7000 items about microcomputers and
workstations, which allows microcomputer users to research possible causes of
hardware and software problems easily. Gopher is also used to post job
opportunities and make text data bases easily accessible at sites around the
world. Gopher is also used to distribute news: the University of Minnesota
campus newspaper, the Minnesota Daily, is available on-line in full-text
searchable format, as are weather reports for the entire US.
One of Gopher's strengths is that information at a server in Italy can easily
be referenced by a server in Indiana, and geographically distributed servers
are accessed transparently by the user. How is this done? A Gopher client is
configured with the address of a single Gopher server. When the client is
launched, it contacts this server for an initial list of items to display to
the user. Each item has a type associated with it so that the client software
can differentiate between documents, directories, search engines, sounds, etc.
The type descriptor also makes it easy to add functionality to the Gopher
protocol by defining new types.
Each item also has a name (to be displayed to the user), a selector string (to
be sent to a server to get the contents of the item), and the port and name of
the machine on which the item resides. The machine name and port can easily be
used to refer to other Gopher servers; this makes it easy to construct links
(pointers) to items that reside on other servers. These links can refer to
individual documents, search engines, or directories (collections of items).
Because there are gateways from Gopher to other services, Gopher clients can
transparently access information on non-Gopher servers including WAIS, Archie,
file transfer protocol (ftp), and USENET news. The Gopher gateway to Archie
translates ftp sites listed by Archie into items that a Gopher client can
access directly through the Gopher-to-ftp gateway; this makes finding and
fetching items via anonymous ftp seamless with a Gopher client.
As of December 1992, there are over 500 Gopher servers on the Internet and
over one million items available on these servers. This growth created the
demand for a way of searching for items across all of the gopher servers. The
University of Nevada has developed a service called VERONICA (very easy
rodent-oriented net-wide index to computerized archives), which is a
searchable index of item names for most of the gopher servers. The addition of
VERONICA to the Internet Gopher's bag of tricks makes it even easier to find
what one is looking for.
Exact measures of Gopher usage are difficult since the servers are so widely
distributed. The only way of exactly measuring usage would be to look at all
the servers simultaneously, and this is clearly impractical. Still, it is
interesting to know that between November 2 and December 7, 1992, the two main
gopher servers at the University of Minnesota saw requests from 35,000
different hosts and handled just over one million transactions.
Gopher software is available for anonymous ftp from boombox.micro. umn.edu in
the pub/gopher directory. (Clients: Macintosh, PC, NeXT, X Windows, VMS,
VM/CMS, and VT-100 terminal; servers: Unix, NeXT, Macintosh, VMS, VM/CMS, and
MVS.) Gopher is discussed on the Gopher-news mailing list (send subscription
requests to gopher-news-request@ boombox.micro.umn.edu) as well as on the
USENET newsgroup comp.infosystems.gopher. For a quick look at gopherspace, you
can telnet to consultant.micro.umn.edu and log in as gopher; for extended
visits to gopher-space you will probably want to run a Gopher client on your
own machine.
