Chapter 8: Information servers (2 of 4) -- WIDE-AREA INFORMATION SERVERS
Chapter 8: Information servers (2 of 4) -- WIDE-AREA INFORMATION SERVERS
Now you know there are hundreds of databases and library catalogs
you can search through. But as you look, you begin to realize that each
seems to have its own unique method for searching. If you connect to
several, this can become a pain. Gophers reduce this problem somewhat.
Wide-area information servers promise another way to zero in on
information hidden on the Net. In a WAIS, the user sees only one
interface -- the program worries about how to access information on
dozens, even hundreds, of different databases. You tell give a WAIS a
word and it scours the net looking for places where it's mentioned. You
get a menu of documents, each ranked according to how relevant to your
search the WAIS thinks it is.
Like gophers, WAIS "client" programs can already be found on many
public-access Internet sites. If it does, type
swais
at the command line and hit enter (the "s" stands for "simple"). If it
doesn't, telnet to bbs.oit.unc.edu, which is run by the University of
North Carolina At the "login:" prompt , type
bbs
and hit enter. You'll be asked to register and will then get a list of
"bulletins,'' which are various files explaining how the system works.
When done with those, hit your Q key and you'll get another menu. Hit 4
for the "simple WAIS client," and you'll see something like this:
SWAIS Source Selection Sources: 23#
Server Source Cost
001: [ archie.au] aarnet-resource-guide Free
002: [ archive.orst.edu] aeronautics Free
003: [nostromo.oes.orst.ed] agricultural-market-news Free
004: [sun-wais.oit.unc.edu] alt-sys-sun Free
005: [ archive.orst.edu] alt.drugs Free
006: [ wais.oit.unc.edu] alt.gopher Free
007: [sun-wais.oit.unc.edu] alt.sys.sun Free
008: [ wais.oit.unc.edu] alt.wais Free
009: [ archive.orst.edu] archie-orst.edu Free
010: [ archie.au] archie.au-amiga-readmes Free
011: [ archie.au] archie.au-ls-lRt Free
012: [ archie.au] archie.au-mac-readmes Free
013: [ archie.au] archie.au-pc-readmes Free
014: [ pc2.pc.maricopa.edu] ascd-education Free
015: [ archie.au] au-directory-of-servers Free
016: [ cirm2.univ-mrs.fr] bib-cirm Free
017: [ cmns-sun.think.com] bible Free
018: [ zenon.inria.fr] bibs-zenon-inria-fr Free
Keywords:
<space> selects, w for keywords, arrows move, <return> searches, q quits, or ?
Each line represents a different database (the .au at the end of some of
them means they are in Australia; the .fr on the last line represents a
database in France). And this is just the first page! If you type a
capital K, you'll go to the next page (there are several pages). Hitting
a capital J will move you back a page.
The first thing you want to do is tell the WAIS program which
databases you want searched. To select a database, move the cursor bar
over the line you want (using your down and up arrow keys) and hit your
space bar. An asterisk will appear next to the line number. Repeat this
until you've selected all of the databases you want searched. Then hit
your W key, after which you'll be prompted for the key words you're
looking for. You can type in an entire line of these words -- separate
each with a space, not a comma.
Hit return, and the search begins.
Let's say you're utterly fascinated with wheat. So you might select
agricultural-market-news to find its current world price. But you also
want to see if it has any religious implications, so you choose the Bible
and the Book of Mormon. What do you do with the stuff? Select recipes
and usenet-cookbook. Are there any recent Supreme Court decisions
involving the plant? Chose supreme-court. How about synonyms? Try
roget-thesaurus and just plain thesaurus.
Now hit w and type in wheat. Hit enter, and the WAIS program begins
its search. As it looks, it tells you whether any of the databases are
offline, and if so, when they might be ready for a search. In about a
minute, the program tells you how many hits it's found. Then you get a
new menu, that looks something like this:
Keywords:
# Score SourceTitleLines
001: [1000] (roget-thesaurus) #465. [results of comparison. 1] Di 19
002: [1000] (roget-thesaurus) #609. Choice. -- N. choice, option; 36
003: [1000] (roget-thesaurus) #465. [results of comparison. 1] Di 19
004: [1000] (roget-thesaurus) #609. Choice. -- N. choice, option; 36
005: [1000] (recipes) aem@mthvax Re: MONTHLY: Rec.Food.Recipes 425
006: [1000] ( Book_of_Mormon) Mosiah 9:96
007: [1000] ( Book_of_Mormon) 3 Nephi 18:185
008: [1000] (agricultural-ma) Re: JO GR115, WEEKLY GRAIN82
009: [ 822] (agricultural-ma) Re: WA CB351 PROSPECTIVE PLANTINGS 552
010: [ 800] ( recipes) kms@apss.a Re: REQUEST: Wheat-free, Suga 35
011: [ 750] (agricultural-ma) Re: WA CB101 CROP PRODUCTION258
012: [ 643] (agricultural-ma) Re: SJ GR850 DAILY NAT GRN SUM72
013: [ 400] ( recipes) pat@jaamer Re: VEGAN: Honey Granola63
014: [ 400] ( recipes) jrtrint@pa Re: OVO-LACTO: Sourdough/Trit 142
Each of these represents an article or citing that contains the word
wheat, or some related word. Move the cursor bar (with the down and up
arrow keys) to the one you want to see, hit enter, and it will begin to
appear on your screen. The "score" is a WAIS attempt to gauge how
closely the citing matches your request. Doesn't look like the Supreme
Court has had anything to say about the plant of late!
Now think of how much time you would have spent logging onto various
databases just to find these relatively trivial examples. But as more
databases are added to WAIS programs, a problem arises that is similar to
the one WAISs were supposed to solve: how do you find the specific
databases you want? Scrolling through page after page of database
listings becomes rather tedious rather quickly and you could wind up
missing the one database you really need. That's the next step in WAIS
research.