Information AboutNewsgroup |
|
HIERARCHIES Newsgroups are often arranged into ''hierarchies'', theoretically making it simpler to find related groups. The term ''top-level hierarchy'' refers to the hierarchy defined by the prefix prior to the first dot.
Further hierarchies There are a number of newsgroup hierarchies outside of the Big 8 (& ALT), that can be found at many news servers. These include non-english language groups, groups managed by companies or organizations about their products, local hierarchies, and even non-internet network boards routed into NNTP. Examples include:
TYPES OF NEWSGROUPS Typically, a newsgroup is focused on a particular topic such as "pigeon hunting". Some newsgroups allow the posting of messages 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 postings. The news admin (the administrator of a News Server ) decides how long articles are kept before being expired (deleted from the server). Usually they will be kept for one or two weeks, but some admins keep articles in local or technical newsgroups around longer than articles in other newsgroups. 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 the ability 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. Newsgroups are much like the public message boards on old Bulletin Board System s. For those readers not familiar with this concept, envision an electronic version of the corkboard in the entrance of your local grocery store. Newsgroups frequently become cliquish and are subject to sporadic Flame Wars and Trolling , but they can also be a valuable source of information, support and friendship, bringing people who are interested in specific subjects together from around the world. There are currently well over 100,000 Usenet newsgroups, but only 20,000 or so of those are active. Newsgroups vary in popularity, with some newsgroups only getting a few posts a month while others get several hundred (and in a few cases several thousand) messages a day. Weblog s have replaced some of the uses of newsgroups (especially because, for a while, they were less prone to Spam ming). A website called DejaNews began Archiving Usenet in the 1990s . DejaNews also provided a searchable web interface. Google bought the archive from them and made efforts to buy other Usenet archives to attempt to create a complete archive of Usenet newsgroups and postings from its early beginnings. Like DejaNews, Google has a web search interface to the archive, but Google also allows newsgroup posting. Non-Usenet newsgroups are possible and do occur, as private individuals or organizations set up their own nntp servers. Examples include the newsgroups Microsoft run to allow peer-to-peer support of their products and those at {Link without Title} . HOW NEWSGROUPS WORK Newsgroup servers are hosted by various organizations and institutions. Most Internet Service Providers host their own News Server , or rent access to one, for their subscribers. There are also a number of companies who sell access to premium news servers.
BINARY NEWSGROUPS While Newsgroups were not created with the intention of distributing binary files, they have proven to be quite effective for this. Due to the way they work, a file uploaded once will be spread and can then be downloaded by an unlimited number of users. More useful is the fact that every user is drawing on the bandwidth of their own news server. This means that unlike P2P technology, the user's download speed is under their own control, as opposed to under the willingness of other people to share files. 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 transmission of binary files over Usenet. Firstly, Usenet was designed with the transmission of text in mind. Due to this, for a long period of time, it was impossible to send binary data as it was. So, a workaround, Uuencode (and later on Base64 and YEnc ), was developed which mapped 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 such 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 Gigabytes of files per day. There are two main issues that pose problems for transmitting binary files over Newsgroups. The first is Completion Rate s and the other is Retention Rates . The business of premium News Server s 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 this, QuickPar is commonly used. A number of websites exist for the purpose of keeping an index of the files posted to binary Newsgroups. SEE ALSO
EXTERNAL LINKS
|
|
|