A B C D E F G H I J K L M N O P Q R S T U V W X Y Z.

(N)

NAMESERVER: A computer running a program that converts domain names into appropriate IP addresses and vice versa.

NAT: NAT (Network Address Translation) is the translation of an Internet Protocol address (IP address) used within one network to a different IP address known within another network. One network is designated the inside network and the other is the outside. Typically, a company maps its local inside network addresses to one or more global outside IP addresses and unmaps the global IP addresses on incoming packets back into local IP addresses. This helps ensure security since each outgoing or incoming request must go through a translation process that also offers the opportunity to qualify or authenticate the request or match it to a previous request. NAT also conserves on the number of global IP addresses that a company needs and it lets the company use a single IP address in its communication with the world.
NAT is included as part of a router and is often part of a corporate firewall. Network administrators create a NAT table that does the global-to-local and local-to-global IP address mapping. NAT can also be used in conjunction with policy routing. NAT can be statically defined or it can be set up to dynamically translate from and to a pool of IP addresses. Cisco's version of NAT lets an administrator create tables that map:
A local IP address to one global IP address statically
A local IP address to any of a rotating pool of global IP addresses that a company may have
A local IP address plus a particular TCP port to a global IP address or one in a pool of them
A global IP address to any of a pool of local IP addresses on a round-robin basis
NAT is described in general terms in RFC 1631. which discusses NAT's relationship to Classless Interdomain Routing (CIDR) as a way to reduce the IP address depletion problem. NAT reduces the need for a large amount of publicly known IP addresses by creating a separation between publicly known and privately known IP addresses. CIDR aggregates publicly known IP addresses into blocks so that fewer IP addresses are wasted. In the end, both extend the use of IPv4 IP addresses for a few more years before IPv6 is generally supported.

NETIQUETTE: Netiquette is etiquette on the Internet. Since the Internet changes rapidly, its netiquette does too, but its still usually based on the Golden Rule. The need for a sense of netiquette arises mostly when sending or distributing e-mail, posting on Usenet groups, or chatting. To some extent, the practice of netiquette depends on understanding how e-mail, the Usenet, chatting, or other aspects of the Internet actually work or are practiced. So a little preliminary observation can help. Poor netiquette because youre new is one thing, but such practices as spam and flaming are another matter.

NETIZEN: The word netizen seems to have two similar meanings.
A citizen who uses the Internet as a way of participating in political society (for example, exchanging views, providing information, and voting).
An Internet user who is trying to contribute to the Internets use and growth. As a powerful communications medium, the Internet seems to offer great possibilities for social change. It also creates a new culture and its own special issues, such as who shall have access to it. The implication is that the Internets users, who use and know most about it, have a responsibility to ensure that is used constructively while also fostering free speech and open access.

NETSCAPE: Netscape is one of the two most popular Web browsers and also the name of a company, Netscape Communications, now owned by America Online (AOL). Currently, almost all Internet users use either Netscape browser or Microsoft Internet Explorer (MSIE) browser, and many users use both. Although Netscape was initially the predominant product in terms of usability and number of users, Microsoft browser is now considered superior by many users (although many other users see them as roughly equivalent) and has taken a slight lead in usage.
Netscape browser originally was called "Navigator," and is still called that in the suite of software, Communicator, of which it is now a part. Navigator was developed in 1995 by a team led by Marc Andreessen, who created Mosaic, the first Web browser that had a graphical user interface, at the University of Illinois National Center for Supercomputing Applications (NCSA) in 1993.
The latest version of Netscape Navigator is 4.72 , now available in a beta version. Navigator can be downloaded as part of the Communicator suite from Netscape Web site at no charge. CD-ROM versions can also be purchased in computer stores and are sometimes distributed freely as promotions.
A primary source of revenue for Netscape and AOL is the Netscape line of Web server products that it develops and has marketed on the success of its wide-scale browser usage. Netscape and AOL also envision the Netscape Web site, now transformed into a leading Web portal, as a leading source of revenue through advertising and e-commerce.

NETWORK: In information technology, a network is a series of points or nodes interconnected by communication paths. Networks can interconnect with other networks and contain subnetworks.
The most common topologies or general configurations of networks include the bus, star, and ring topologies. Networks can also be characterized in terms of spatial distance as local area networks (LANs), metropolitan area networks (MANs), and wide area networks (WANs).
A given network can also be characterized by the type of data transmission technology in use on it (for example, a TCP/IP or SNA network); by whether it carries voice, data, or both kinds of signals; by who can use the network (public or private); by the usual nature of its connections (dial-up or switched, dedicated or non-switched, or virtual connections); and by the types of physical links (for example, optical fiber, coaxial cable, and copper wire). Large telephone networks and networks using their infrastructure (such as the Internet) have sharing and exchange arrangements with other companies so that larger networks are created.

NEWSGROUP: A newsgroup is a discussion about a particular subject consisting of notes written to a central Internet site and redistributed through Usenet, a worldwide network of news discussion groups. Usenet uses the Network News Transfer Protocol (NNTP).
Newsgroups are organized into subject hierarchies, with the first few letters of the newsgroup name indicating the major subject category and sub-categories represented by a subtopic name. Many subjects have multiple levels of subtopics. Some major subject categories are: news, rec (recreation), soc (society), sci (science), comp (computers), and so forth (there are many more). Users can post to existing newsgroups, respond to previous posts, and create new newsgroups.
Newcomers to newsgroups are requested to learn basic Usenet "netiquette" and to get familiar with a newsgroup before posting to it. A FAQ is provided. The rules can be found when you start to enter the Usenet through your browser or an online service. You can subscribe to the postings on a particular newsgroup.
Some newsgroups are moderated by a designated person who decides which postings to allow or to remove. Most newsgroups are immoderate.

NEWSREADER: Program that allows the user to read Newsgroup messages via Usenet, such as the in built newsreaders in Internet Explorer or Netscape. There are also dedicated newsreaders such as Forte Agent.

NIC: Networked Information Center -- Generally, any office that handles information for a network. The most famous of these on the Internet is the InterNIC, which is where new domain names are registered.
Another definition: (NIC) is a computer circuit board or card that is installed in a computer so that it can be connected to a network. Personal computers and workstations on local area networks (LANs) typically contain a network interface card specifically designed for the LAN transmission technology, such as Ethernet or Token Ring. Network interface cards provide a dedicated, full-time connection to a network. Most home and portable computers connect to the Internet through as-needed dial-up connection. The modem provides the connection interface to the Internet service provider.

NNTP: NNTP (Network News Transfer Protocol) is the predominant protocol used by computers (servers and clients) for managing the notes posted on Usenet newsgroups. NNTP replaced the original Usenet protocol, UNIX-to-UNIX Copy Protocol (UUCP) some time ago. NNTP servers manage the global network of collected Usenet newsgroups and include the server at your Internet access provider. An NNTP client is included as part of a Netscape, Internet Explorer, Opera, or other Web browser or you may use a separate client program called a newsreader.

NODE: In a network, a node is a connection point, either a redistribution point or an end point for data transmissions. In general, a node has programmed or engineered capability to recognize and process or forward transmissions to other nodes.