Usenet (also known under the name Netnews ) is a system in network of discussion forums, invented in 1979 and based on the protocol NNTP. It was quickly made usable via Internet where there remains of use today.
Some find it less easy to use than the forums Web (appeared in the years 2000) but it has as main advantages allowing a faster reading (because less personalized and disturbed visually) and to facilitate the replication of the articles on the waiters of the whole world.
Nowadays, the majority of the newcomers on Internet discover and use Usenet via the Groups heading of Google.
Usually, the use (reading or writing) takes place via a software said Lecteur of news or newsreader in English.
General operation
Usenet is a whole of protocols being used for generating, storing and recovering “articles” (messages which are close, in their structure, of the emails), and allows the exchange of these articles between the members of a community which can be distributed on a zone potentially very wide. Usenet is organized around the principle of newsgroups or groups of news (in English newsgroup ), which gathers each article (contributions) on a precise subject. The subjects of the newsgroups are organized according to a hierarchy. Once connected to a data-processing Waiter providing a Usenet service, the users can choose the groups placed at the disposal by this waiter to which they wish “to subscribe”. For each group to which he is subscribed, the user can then see all the new articles placed at the disposal on this group and all the articles received by the waiter for a certain time. The old articles are automatically unobtrusive waiter; according to the waiters, this time can vary between one month and a few days. However, there exist waiters of filing, such as Google Groups or Gmane, which makes it possible to consult the old articles of certain newsgroups, in the same way presented that the files of Liste of discussion.When a user sends an article on a Usenet waiter, this one propagates it with all the other waiters with which it concluded from the agreements of exchange of articles ( feeding , literally, “food”), and so on. Each waiter preserves a copy of this article, and can then place it at the disposal of the users having access to this waiter.
The users generally employ software customers called Lecteur of news (sometimes also called customer of news , in reference to the model Client-serveur) for reading and composing of the Usenet articles. The majority of the customers of transport integrate a module of reading of more or less complete the Usenet articles.
Beginnings of Usenet
Usenet was created in 1979 by a group of students of North Carolina: Tom Truscott, Jim Elect, Denis Rockwell and Steve Daniel, of Dake, and Steve Bellovin, of Chapel Hill. It was thus born after the email (1972) and after TCP/IP (1974), but before DNS (1983) and well before the World Wide Web (1989). The name Usenet was an abbreviation of Unix User Network ; one regards it today as a proper name.
Usenet, at the origin independent, was quickly connected to ARPANet, the future Internet. In practice, today, the totality of the Usenet traffic passes by Internet. But certain users enjoy to recall that “Usenet is not pas Internet” and could exist without.
In 1986, the protocol UUCP, used at the origin for the transport of the news , was replaced by NNTP, was conceived especially. In the two years which followed, the , reorganization of the groups to face the growth and with the internationalization of the network, gave to Usenet its current overall structure.
Organization
For this time, the groups have been arranged according to various criteria in one tree structure. The name of a group is made of several components, separated by points; and each component corresponds to a level of tree structure. It is read from left to right: for example, fr.edu cation.superior is a group French-speaking person, devoted to education, and more particularly to teaching superior. The whole of the groups located in the same branch of the tree structure, i.e. which has first identical components, is called one hierarchy. One often uses the symbol * to indicate unspecified characters: thus, one writes comp.* to indicate the whole of the groups of the hierarchy comp .
Each waiter can choose to diffuse or not for its users, and of to propagate or not with its neighbors, contents of each group. Generally, the administrator does not choose the groups one by one, but selects whole hierarchies.
The heart of Usenet is the Big Eight or Big8 , formed of the eight principal ones international hierarchies: comp (computers), misc (various), news (operation of the newsgroup), rec (leisures), sci (sciences), plowshare (company) and talk (debates), created at the time of Great Renaming, and humanities (letters, social sciences), added thereafter. Big8, except sometimes for the hierarchy talk , is largely propagated. One there discusses mainly but not only in English.
There exist two other important international hierarchies, where rules - enough strict - of operation of the Big8 are softened. On biz.* , publicity is authorized. On alt.* , no matter who can create a group, and on alt.binaries.* it is allowed to publish enclosures.
There is then a certain number of “national” hierarchies Some, like the principal French-speaking hierarchy Usenet-Fr, actually correspond to a language and not to a country. Most important are almost as well propagated as the Big8 .
Lastly, one finds a great number of minor hierarchies, with the rather random propagation. It can be a question of complete and independent networks of discussion, spaces of discussion set up by companies… Many waiters offer a local hierarchy “private” which is sometimes propagated outside. The hierarchy microsoft.public.* is a known example.
Future of Usenet?
The number of contributions and authors is in fall since 2003. Usenet seems to suffer from the competition of the Web: (forums Web, blogs and wikis).
Technical operation
Articles
To read the news, the user uses a specialized software, the Reader of news or newsreader . This one is connected to a News server. The dialog with the waiter uses the protocol NNTP, described in RFC 977, and is held in general on port 119. Once connected, the software can recover the list groups available, the list of the articles of a group (in fact, theirs headings), or contents of a given article. It can also poster of the articles, by sending them to the waiter.
The format of the articles, described in RFC 1036, resemble that of the emails much. An article starts with headings of the form Field: value There is a great number of headings standardized, for to indicate the shipper, the date, the subject, the groups where to publish the article… The readers of news fill them automatically. It is possible to add its own headings; the name of the field must then to start with X, for example X-No-Files . Follow a virgin line then the body of the article itself.
The whole must be in rough text. The only coding of the text gross readable on any Usenet ASCII is . According to the groups, it is possible, by indicating it in the headings, to send coded messages ISO-8859 on 8 bits, and in particular in the character sets adapted to languages of Western Europe: ISO 8859-1 (latin1) and ISO 8859-15 (latin9). Lastly, in some rare groups, one can use Unicode, in general coded in UTF-8.
Each article carries a single identifier, the Message-Id . It is the way principal to refer there. It should be noted on this subject that an article does not belong to a particular group. It is simply posted on the network, and visible in the groups where it is posted according to its headings. That allows poster the same article in several groups while transporting one specimen. (It is well seen not to misuse this process, called crosspost .)
The waiter must then propagate the article.
Waiters and propagation
The first versions of Usenet used the software B-News, then C-News like server softwares. In the Years 1990, INN was developed to draw advantage from the architecture of Internet, which supported an operation other than the method store-to make follow of UUCP. The development of INN continues to date, and other Usenet waiters also appeared meanwhile.
To install a waiter of news, one should first of all be gotten feed , i.e. a connection to another waiter (sufficient important) which will be able to transmit to the new waiter the traffic of the remainder of Usenet. Waiters neighbors contact themselves regularly to propagate the articles. Schematically, they compare their lists of articles, and each one sends to the other what it is the only one to have. Naturally, waiters of news preserve and propagate only the sufficiently recent articles.
As regards the changes in the structure of the groups itself, of the special articles, called messages of control, indicate to each waiter them modifications of the tree structure. Free with each administrator to be unaware of certain groups. No matter who can send a message of control, but them waiters are configured to accept, for such hierarchy, only them messages signed by such private key of asymmetrical cryptography. Messages of control “pirates” are thus ignored - unless the administrator of waiter does not decide any differently.
The classification of the largest waiters of newsgroup is held by the top1000.org site.
Addresses and access to the resources
Remain a last point, that of the identification of a waiter, of a group or a message. As about all that is accessible by Internet, these resources can be indicated by textual “addresses”, the Universal Resource To identify S or URI.
The addresses relating to Usenet are not completely standardized. The RFC 1738 define three kinds of them, but one finds others of them still (see the RFC 2396 and the Internet Draft draft-gilmain-news-URL-02 and draft-stockwell-hnews-URL-00).
Syntax
news:
Lastly,
NNTP: //
Let us note that some Web sites make it possible to read the largely distributed Usenet forums and of there poster; these sites in general offer also a function of file (see hereafter).
The whole of the articles posted on Usenet was not always filed. However, of 1995 with 2001, the Deja.com company (become DejaNews.com in 1997) carried out such a work of filing and placed at the disposal of the Net surfers a platform of search then for sending of articles. In December 2001, the Search engine Google repurchased DejaNews.com and its base of articles, then added a file of articles going up until the beginnings of Usenet. These files incomplete, but nevertheless are very provided. It is in particular possible to find historical messages there, as the advertisement of the World Wide Web made by Tim Berners Lee in news:alt.hypertext and the advertisement of Linux made by Linus Torvalds in news:comp.os.minix.
Historically, Usenet was developed to distribute rough text using the character set 7 bits ASCII. Using programs which code data 8 bits like continuations of ASCII natures 7 bits, it is possible to transfer by Usenet from the binary Fichiers unspecified. Because of their size and their sometimes doubtful legality, the articles containing of the binary files are accepted only on specific groups, which allows to the administrators waiters to easily accept or refuse to distribute them.
Oldest of these methods of coding is uuencode, initially developed for UUCP. At the end of the Years 1980, much of waiters limited the length of the articles to 60.000 characters; and such limits always exist, even if they are generally higher. For this reason, the data of a file are divided into various articles and must be reassembled by the Lecteur of news.
It happens that certain parts of a file are not downloadable any more (indeed the waiters keep the binary messages only a few days) or although certain parts are erroneous. To mitigate this problem, one often meets files BY which are additional data to download and allow to rebuild the missing parts. In general the files BY make 10% of the total size of the file be downloaded.
With the extensions of the format of the articles (Base64, “Quoted-Printable”, MIME) new possibilities for the transport of binary contents appeared. In practice, MIME is used more and more in the messages, but to hardly transmit binary enclosures. In addition, certain operating systems which associate with the files auxiliary information (Métadonnées) require special formats. Mac OS uses for example Binhex and of specific types MIME.
For better using the capacities of the Usenet network and increasing the speed of transfer, the procedure of coding YEnc was developed in 2001. It uses less space than usual codings while supposing than the majority of the characters 8 bits can be transmitted correctly.
Software specialized in downloading files binary: Loi of Godwin
Files discussions
Transport of binary files
Software
Explanations
The binary files deposited on the newsgroup being cut out in several parts (multi-parts), they should be reassembled once all the finished remote loadings. Software appeared in order to facilitate and to accelerate the remote loading but also to stop it to take it again later. Many of other options are available and vary according to the programs.
Most known
See too
Related articles
External bonds
Random links: March 1977 | Route main road 767 | Pierre of the Rocks | PROJ-x | Nijmegen Emperors