Usenet newsgroup

A Usenet newsgroup is a repository usually within the Usenet system, for messages posted from many users in different locations using Internet. (Despite the name, newsgroups are discussion groups. They are not devoted to publishing news, although they had been so intended when the internet was young.[vague]) Newsgroups are technically distinct from, but functionally similar to, discussion forums on the World Wide Web. Newsreader software is used to read the content of newsgroups.

Before the adoption of the World Wide Web, Usenet newsgroups were among the most popular Internet services, and have retained their noncommercial nature in contrast to the increasingly ad-laden web. In recent years, this form of open discussion on the Internet has lost considerable ground to individually-operated browser-accessible forums and big media social networks such as Facebook and Twitter.

Communication is facilitated by the Network News Transfer Protocol (NNTP) which allows connection to Usenet servers and data transfer over the internet. Similar to another early (yet still used) protocol SMTP which is used for email messages. NNTP allows both server-server and client-server communication - this means that newsgroups can be replicated from server to server which gives the Usenet network the ability to maintain a level of robust data persistence as a result of built-in data redundancy. However, most users will access using only the client-server commands of NNTP and in almost all cases will use a GUI for browsing as opposed to command line based client-server communication specified in the NNT protocol.[1]

Types

Newsgroups generally come in either of two types, binary or text. There is no technical difference between the two, but the naming differentiation allows users and servers with limited facilities to minimize network bandwidth usage. Generally, Usenet conventions and rules are enacted with the primary intention of minimizing the overall amount of network traffic and resource usage. Typically, the newsgroup is focused on a particular topic of interest. A message sent for publication on a newsgroup is called a "post". Some newsgroups allow posts on a wide variety of themes, regarding anything a member chooses to discuss as on-topic, while others keep more strictly to their particular subject, frowning on off-topic posts. The news admin (the administrator of a news server) decides how long posts are kept on their server before being expired (deleted). Different servers will have different retention times for the same newsgroup; some may keep posts for as little as one or two weeks, others may hold them for many months. Some admins keep posts in local or technical newsgroups around longer than posts in other newsgroups.

Back when the early community was the pioneering computer society, the common habit seen with many posts was a notice at the end that disclosed whether the author had (or was free of) a personal interest (financial, political or otherwise) in making the post. This is rarer now, and the posts must be read more skeptically, as with other media. Privacy and phishing issues have also risen in importance.

The number of newsgroups grew from more than 100 as of 1983[2] to more than 110,000, but only 20,000 or so of those are active.[citation needed] Newsgroups vary in popularity; some newsgroups receive under a dozen posts per year while the most popular can get several thousand in under an hour.

Non-Usenet newsgroups are possible and do occur, as private individuals or organizations set up their own NNTP servers. Examples include the newsgroups news://news.grc.com.

Binary

While newsgroups were not created with the intention of distributing files such as pictures, sound and video, they have proven to be quite effective for this. Because newsgroups are widely distributed, a file uploaded once will be spread to many other servers and can then be downloaded by an unlimited number of users. More useful is that users download from a local news server, rather than from a more distant machine with perhaps limited connectivity, as may be the case with peer-to-peer technology. In fact, this is another benefit of newsgroups: it is usually not expected that users share. If every user makes uploads then the servers would be flooded; thus it is acceptable and often encouraged for users to just leech.

There were originally a number of obstacles to the transfer of binary files over Usenet. Usenet was originally designed with the transmission of text in mind, and so the encoding of posts caused losses in binary data where the data was not part of the protocol's character set. Consequently, for a long while, it was impossible to send binary data as such. As workarounds, codecs such as Uuencode and later Base64 and yEnc were developed which encoded the binary data from the files to be transmitted (e.g. sound or video files) to text characters which would survive transmission over Usenet. At the receiver's end, the data needed to be decoded by the user's news client.

Additionally, there was a limit on the size of individual posts so that large files could not be sent as single posts. To get around this, Newsreaders were developed which were able to split long files into several posts. Intelligent newsreaders at the other end could then automatically group such split files into single files, allowing the user to easily retrieve the file. These advances have meant that Usenet is used to send and receive many terabytes of files per day.

There are two main issues that pose problems for transmitting large files over newsgroups. The first is completion rates and the other is retention rates. The business of premium news servers is generated primarily on their ability to offer superior completion and retention rates, as well as their ability to offer very fast connections to users. Completion rates are significant when users wish to download large files that are split into pieces; if any one piece is missing, it is impossible to successfully download and reassemble the desired file. To work around the problem, a redundancy scheme known as Parchive (PAR) is commonly used.

Major NSPs have a retention time of more than 7 years.[3] A number of websites exist to keep an index of files posted to binary newsgroups.

Partly because of such long retention times, as well as growing uploading and downloading speeds, Usenet is also used by individuals to store backup data in a practice called Usenet backup, or uBackup.[4] While commercial providers offer easier-to-use online backup services, storing data on Usenet is free of charge (although access to Usenet itself may not be). A user must manually select, prepare and upload the data. Because anyone can download the backup files, the data is typically encrypted. After the files are uploaded, the uploader has no control over them; they are automatically distributed to all Usenet providers that subscribe to the newsgroup they are uploaded to, so there will be copies of them spread all around the world.

Moderated newsgroups

Most Newsgroups are not moderated. A moderated newsgroup has one or more individuals who must approve posts before they are published. A separate address is used to submit posts and the moderators then propagate those they approve of. The first moderated newsgroups appeared in 1984 under mod.* according to RFC 2235, "Hobbes' Internet Timeline".

Other Languages
Ænglisc: Tīdunghēap
Deutsch: Newsgroup
Esperanto: Novaĵgrupo
فارسی: گروه خبری
Gaeilge: Nuachtghrúpa
한국어: 뉴스그룹
Bahasa Indonesia: Newsgroup
italiano: Newsgroup
Nederlands: Nieuwsgroep
português: Grupo de notícias
svenska: Nyhetsgrupp
Türkçe: Haber grubu
українська: Група новин
粵語: 新聞組
中文: 新闻组