Книга: Fedora™ Unleashed, 2008 edition
Usenet Network Newsgroups
Usenet Network Newsgroups
The concept of newsgroups revolutionized the way information was exchanged between people across a network. The Usenet network news system created a method for people to electronically communicate with large groups of people with similar interests. As you will see, many of the concepts of Usenet news are embodied in other forms of collaborative communication.
Usenet newsgroups act as a form of public bulletin board system. Any user can subscribe to individual newsgroups and send (or post) messages (called articles) to the newsgroup so that all the other subscribers of the newsgroup can read them. Some newsgroups include an administrator, who must approve each message before it is posted. These are called moderated newsgroups. Other newsgroups are open, allowing any subscribed member to post a message. When an article is posted to the newsgroup, it is transferred to all the other hosts in the news network.
Usenet newsgroups are divided into a hierarchy to make it easier to find individual news groups. The hierarchy levels are based on topics, such as computers, science, recreation, and social issues. Each newsgroup is named as a subset of the higher-level topic. For example, the newsgroup comp relates to all computer topics. The newsgroup comp.laptops relates to laptop computer issues. Often the hierarchy goes several layers deep. For example, the newsgroup comp.databases.oracle.server relates to Oracle server database issues.
NOTE
The format of newsgroup articles follows the strict guidelines defined in the Internet standards document Request For Comments (RFC) 1036. Each article must contain two distinct parts: header lines and a message body.
The header lines identify information about when and by whom the article was posted. The body of the message should contain only standard ASCII text characters. No binary characters or files should be posted within news articles. To get around this restriction, binary files are converted to text data, through use of either the standard UNIX uuencode program or the newer Multipurpose Internet Mail Extensions (MIME) protocol. The resulting text file is then posted to the newsgroup. Newsgroup readers can then decode the posted text file back into its original binary form.
A collection of articles posted in response to a common topic is called a thread. A thread can contain many articles as users post messages in response to other posted messages. Some newsreader programs allow users to track articles based on the threads to which they belong. This helps simplify the organization of articles in the newsgroup.
TIP
The free news server news.gmane.org makes the Red Hat and Fedora mail lists avail able via newsgroups. It is a handy way to read threaded discussions and easier than using the Fedora mail list archives.
The protocol used to transfer newsgroup articles from one host to another is Network News Transfer Protocol (NNTP), defined in RFC 975. (You can search RFCs at ftp://metalab.unc.edu/pub/docs/rfc/; look at the file rfc-index.txt.) NNTP was designed as a simple client/server protocol that enables two hosts to exchange newsgroup articles in an efficient manner.
Оглавление книги
- Linux Usenet Newsgroups
- What Is Usenet, Anyway?
- How Does Usenet Handle News?
- Connecting to network drives
- Renaming network connections
- CHAPTER 14 Networking
- Installing Using a Network
- Network Configuration
- Configuring Wireless Networks
- Network Storage
- Using Network Configuration Tools
- Command-Line Network Interface Configuration