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Glossary: CCNA & General Networking Terms 


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See: Negative Acknowledgment
See: Network Address Translation.
name resolution
The process of mapping a name into its corresponding address. See also: Domain Name System. [Source: RFC1208]
Name Registration Scheme
All sites connected to JANET via X25 were expected to register with the national 'Name Registration Scheme' (NRS). The NRS maintained a database which recorded, for each service on each site (such as X29 or Coloured Book mail), a 'standard' name and an 'abbreviated name' for that service, together with its numeric JANET address. The full form of identification using an NRS name was: UK.AC. . . With the replacement of X25 by IP services, the NRS did not last usefully beyond mid-1997.
name resolution
The process of mapping a name into the corresponding address. See also: DNS. [Source: RFC1208]
Name Server
software which matches mnemonic names to raw addresses. This might be a Campus Name Server for local PCs (using a JNT protocol called Name Lookup Protocol or NLP), or a Domain Name Server for local hosts on an Internet site - such as the Bradford campus network.
Name Server record
A DNS resource record type indicating which host can provide the Domain Name Service facilities for a particular domain. See also: Domain Name System.
A commonly distributed set of names in which all names are unique. [Source: MALAMUD]
National Institute of Standards and Technology (NIST)
United States governmental body that provides assistance in developing standards. Formerly the National Bureau of Standards. [Source: MALAMUD]
National Research and Education Network (NREN)
The NREN is the realization of an interconnected gigabit computer network devoted to Hign Performance Computing and Communications. See also: HPPC, IINREN. [Source: HPCC]
National Science Foundation (NSF)
A U.S. government agency whose purpose is to promote the advancement of science. NSF funds science researchers, scientific projects, and infrastructure to improve the quality of scientific research. The NSFNET, funded by NSF, was once an essential part of academic and research communications. It wass a highspeed "network of networks" which is hierarchical in nature. At the highest level, it had a backbone network of nodes, interconnected with T3 (45Mbps) facilities which spanned the continental United States. Attached to that were mid-level networks and attached to the mid-levels were campus and local networks. See also: backbone network, mid- level network. [Source: RFC1983]
Negative Acknowledgment (NAK)
Response to receipt of a corrupted packet of information. See also: Acknowledgement. [Source: RFC1392]
Network Basic Input Output System. The standard interface to networks on IBM PC and compatible systems before the rise of TCP/IP.
An inhabitant of Cyberspace. One usually tries to be a good net.citizen, lest one be flamed.
A research prototype to provide a simple Internet "white pages" user directory. Developed at the University of Colorado, Boulder, it tries to locate telephone and email information given a person's name and a rough description of where the person works. See also: Knowbot, whois, white pages, X.500. [Source: Ryan Moats]
A pun on "etiquette" referring to proper behavior on a network. RFC 1855 (FYI 28) contains a netiquette guide produced by the User Services area of the IETF. See also: Acceptable Use Policy, Internet Engineering Task Force. [Source: RFC1983]
See: Usenet
A computer network is a data communications system which interconnects computer systems at various different sites. A network may be composed of any combination of LANs, MANs or WANs. See also: Local Area Network, Metropolitan Area Network, Wide Area Network, internet. [Source: RFC1392]
network address
The network portion of an IP address. For a class A network, the network address is the first byte of the IP address. For a class B network, the network address is the first two bytes of the IP address. For a class C network, the network address is the first three bytes of the IP address. In each case, the remainder is the host address. In the Internet, assigned network addresses are globally unique. See also: Internet, IP address, subnet address, host address, Internet Registry, OSI Network Address. [Source: RFC1392]
Network Address Translation (NAT)
A method of converting between a range of IP addresses on the public side of a routing device, and a (typically smaller) range of IP addresses on the private side. Often used as to conserve IP addresses, since the private side can use "unrouteable" ranges of IP numbers, which can be safely re-used in many such locations. Also used to conceal identities of private hosts when implemented as part of a firewall. See also: Unroutable Address, IP Address.
Network File System (NFS)
A protocol developed by Sun Microsystems, and defined in RFC 1094, which allows a computer system to access files over a network as if they were on its local disks. This protocol has been incorporated in products by more than two hundred companies, and is now a de facto Internet standard. [Source: NNSC]
Network Information Center (NIC)
A NIC provides information, assistance and services to network users. See also: Network Operations Center. [Source: RFC1392]
Network Information Services (NIS)
A set of services, generally provided by a NIC, to assist users in using the network. Also a service used by UNIX administrators to manage databases distributed across a network (a product of Sun Microsystems(R) - formerly known as Yellow Pages). See also: Network Information Center. [Source: RFC1392]
Network Layer
The OSI layer that is responsible for routing, switching, and subnetwork access across the entire OSI environment. [Source: RFC1208]
network mask
See: address mask
Network News Transfer Protocol (NNTP)
A protocol, defined in RFC 977, for the distribution, inquiry, retrieval, and posting of news articles. See also: Usenet. [Source: RFC1392]
network number
See: network address
Network Operations Center (NOC)
A location from which the operation of a network or internet is monitored. Additionally, this center usually serves as a clearinghouse for connectivity problems and efforts to resolve those problems. See also: Network Information Center. [Source: NNSC]
Network Time Protocol (NTP)
A protocol that assures accurate local timekeeping with reference to radio and atomic clocks located on the Internet. This protocol is capable of synchronizing distributed clocks within milliseconds over long time periods. It is defined in STD 12, RFC 1119 (POSTSCRIPT format) and updated in RFC 1305. See also: Internet. [Source: NNSC]
See: Network File System
National Grid for Learning.
NIC (1)
See: Network Information Center
NIC (2)
Network Interface Card.
This is the domain name of the DDN NIC. See also: Defense Data Network..., Domain Name System, Network Information Center. [Source: RFC1983]
Network Independent File Transfer Protocol. See Blue Book and FTP.
National Information and Learning Technology Association. An Affiliated Group of the JANET National User Group.
See: Network Information Services
National Information Services and Systems. A JISC service carrying professionally maintained online information services for and about the education sector.
See: National Institute of Standards and Technology
National Learning Network.
Network Management Station. The system responsible for managing a (portion of a) network. The NMS talks to network management agents, which reside in the managed nodes, via a network management protocol. See agent. [Source: RFC1208]
See: Network News Transfer Protocol
Network North West, a Metropolitan Area Network for Manchester and environs.
See: Network Operations Center
Nodal Switching System (NSS)
Main routing nodes in the NSFnet backbone. See also: backbone, National Science Foundation. [Source: MALAMUD]
An addressable device attached to a computer network. See also: host, router. [Source: RFC1392]
North East Metropolitan Area Network.
North West JANET Regional User Group (NWJRUG)
The North West JANET Regional User Group represents the views of users of JANET within the ancient regions of Staffordshire, Cheshire, Lancashire and Cumbria, plus any modern additions. See also: JANET National User Group.
Network Operations and Service Centre.
See: National Research and Education Network
see Name Registration Scheme.
See: Name Server record
Network Service Access Point. The point at which the OSI Network Service is made available to a Transport entity. The NSAPs are identified by OSI Network Addresses. [Source: RFC1208]
See: National Science Foundation
See: Nodal Switching System
New Technology, a version of Microsoft Windows operating system. The initials WNT bear the same relationship to VMS as IBM does to HAL. I'm sorry Dave...
Network Time Protocol, defined by RFC 958, and updated to version 3 in RFC 1305, provides the mechanisms to synchronise hosts and coordinate time distribution in a large diverse internet.
Network Termination Unit
See: North West JANET Regional User Group


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