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Archie the list into the list into the list into the list into the reception.
URL-address indicating FTP-connection, owes, as a minimum to include a word “ftp” as the left part and address of the site in right:
ftp: // < the address of the server >.
WAIS
Almost all information resources Internet give an opportunity of automatic search, but only in one of them - in system WAIS (Wide Area Information Server, global information server) - the keyword search, is the basic method of access to the information.
The system WAIS represents the huge distributed(allocated) database, i.e. the separate parts of this database are located on different net points worldwide. The program - client for work with servers WAIS not only is able to communicate with them under the special protocol, but also stores(keeps) the list of all databases WAIS with their addresses and names, and sometimes and with the brief descriptions. There it is possible to find archives of news, every possible catalogues, directories, collections of scientific clauses and abstracts, indexes and much another. Practically any information, for which the database is the convenient form by performances which is interesting enough to a wide audience, can be submitted in WAIS.
The database WAIS is so great, that idle time of recordings - extremely unpromising way of access to the information. Therefore in WAIS the rather complex(difficult) method of keyword search and phrases is applied. The documents received as a result of search, are sorted by the WAIS-server by quantity(amount) of entry in them of keywords and on, as far as is complete in each of them all set of the ordered keywords is submitted. Such system is capable to give good results, is especial if to break process of search at some stages.
The first stage of search usually is the search special in a database under the name “directory-of-servers”, which contains small on volume of the description (abstracts) of all other bases WAIS. Thus it is better to specify not those keywords, which at the end interest you, and those general(common) concepts concerning your field of knowledge.
Having chosen on the first stage of one or several bases, it is possible to begin search actually of documents - that also it is possible to do(make) in some calls, getting acquainted after each search with results and changing the list of keywords, the necessary document will not be found yet. Besides WAIS has one useful property: if at the next stage of search you have found the document, which contents are especially close that you search, it(he) can be added to the list of the relevant documents. In result at the following stage WAIS will find the documents, not only containing a set of your keywords, but also similar on the dictionary structure on those texts, which you have specified as most suitable.
Though Netscape is capable to work with servers WAIS, for this purpose it(he) should know the address of the special proxy for the protocol WAIS, of which your provider can not appear. The special WAIS-clients working including under Windows, not only convenient for interactive search in databases, but also allows to manage services any of the server – intermediary.
URL-address for WAIS looks as:
wais: // < the address of the server > / < the name of base >
Gopher
Each of the considered till now Internet protocols quite could exist in itself: telnet gives access to the programs, FTP - to files, WAIS - to databases. All these systems were created both developed almost independently from each other and put before itself the concrete purpose - to construct the mechanism of access to one certain kind of resources.
However as Internet of dews also became complicated, it(he) pushed the people to an idea, that the information on a nature is uniform and what not too reasonably to divide her(it) on different “ kinds of resources ” with unlike methods of access. By the end of 80-s' years the idea of a new universal remedy of work with the diverse information was carried in air.
Реферат опубликован: 5/12/2009