NAG
Numerical Algorithms Group

NAME SERVER
Name servers are setup to maintain host addresses for each sub-domain or zone within the name space as well as to maintain the address of root name server. Using recursive, queries or referring clients to other servers, a DNS server is capable of resolving the IP address for any host in the Internet.

NAP
See Network Access Point (NAP) /.

NAPLPS
North American Presentation Layer Protocol Syntax.

NAS Network Application Support:
DEC's approach to applications integration across a distributed multivendor environment.

NASA
National Aeronautics and Space Administration (USA). NASA has many software engineering projects

NASD See Network Attached Storage Device (NASD) /.

National Center for Supercomputing Applications (NCSA)
The National Center for Supercomputing Applications (NCSA), located at the University of Illinois at Urbana-Champaign, is a high-performance computing and communications facility and research center designed to serve the U.S. computational science and engineering community.

Native Address
An address that matches one of a given node's summary addresses.

Navigator
A browser developed by Netscape, and the first to support Java Script.

NBS National Bureau of Standards:
part of the U.S. Department of Commerce, now NIST NIST.

NCOSE
National Council On Systems Engineering (USA) - . /NCOSE

NCS Network Computing System:
Apollo's RPC RPC system used by DEC and Hewlett-Packard.The protocol has been adopted by OSF OSF.

NCSA
National Center for Supercomputing Applications, Urbana, IL, USA

NCSS
Non-Commented Source Statements. Used as a simple software metric.

NDIS Network Driver Interface Specification:
Refer to 3COM/Microsoft, LAN Manager: Network Driver Interface Specification, October 8, 1990.

NDL National Database Language:
a US standard for portability of database definitions and application programs.

NDMP
See Network Data Management Protocol (NDMP) /.

NE Network Element:
A system that supports at least NEFs and may also support Operation System Functions/Mediation Functions. An ATM NE may be realized as either a standalone device or a geographically distributed system. It cannot be further decomposed into managed elements in the context of a given management function.

NEF Network Element Function:
A function within an ATM entity that supports the ATM based network transport services, (e.g., multiplexing, cross-connection).

Negative caching
Some DNS /d servers keep the answer "no such host or domain" cached to minimize response time to the resolver /r.

Neighbor Node
A node that is directly connected to a particular node via a logical link.

NEL Network Element Layer:
An abstraction of functions related specifically to the technology, vendor, and the network resources or network elements that provide basic communications services.

Neptune
A hypertext hypertext system for computer assisted software engineering, developed at Tektronix.

Nerd
A person who spends too much time at the computer. A person, for example, who wanders away from dinner parties to check the computer to see whether any good electronic mail has arrived.

NetBEUI Network Basic Input/Output System Extended User Interface.
The primary local area network transport protocol in Windows NT. A simple NetBEUI is not layer transport developed to support NetBIOS installations. NetBEUI is not routable, and so it is not appropriate for larger networks. NetBEUI is the faster transport protocol available for Windows NT.

NetBIOS
A client/server interprocess communication service developed by IBM in the early 1980s. NetBIOS present a relatively primitive mechanism for communication in client/server applications, but its widespread acceptance and availability across most operating systems makes it a logical choice for simple network applications. Many Windows NT network IPC mechanisms are implemented over NetVIOS.

NetBIOS over TCP/IP (NetBT)
A network service that implements the Net BIOS IPC over the TCP/IP protocol stack. See NetBEUI, Transmission Control Protocol/Internet Protocol.

NetCDF
Network Common Data Form. A machine-independent, self-describing file format for scientific data - . /SciDataFormats

NetClasses
A C++ C++ class library class-library for object transport and remote method invocation from Stanford - . ftp://thor.stanford.edu/pub/netclasses/

NetInfo
A hierarchical collection of databases used by NEXTSTEP computers for maintaining administrative information such as user accounts, host entries, printer information, and file system /f mounting data. The hierarchy consists of domains /d, or levels.

Netiquette
Rules of polite behavior for sending electronic mail.

Netnews
See USENET news /u.

Network
A bunch of computers connected by some combination of cables, phone lines, satellites, or whatever. A network enables computers (and their users) to share information and peripherals. They are especially good for sharing printers (so that you can all share good but expensive laser printer) and for passing around electronic mail.

Network
A group of machines that share information and resources. A group of smaller networks or subnetworks. See also internet /i, Local Area Network (LAN) /l, subnet /s, Wide Area Network (WAN) /w.

Network Access Point (NAP)
Telecommunications term for the location where a call (data or voice) enters the telecommunications network.

Network Address
A unique address that identifies each node, or device on the network. The network address is generally hard-coded into the network card on both the workstation and server. Some network cards aloe you to change this address, but there is seldom a reason to do so.

Network address
An IP /i address represented by a four-byte field written as byte1.byte2.byte3.byte4, where each byte is an ASCII /a numeric representation (0 through 255). See also host /h, Internet /i, network /, subnet /s.

network administrator
See system administrator /s.

Network Attached Storage (NAS)
Storage (usually disks but possibly tapes or memory) attached to and distributed (shared) over a network. Usually the environment of a NAS is many computers sharing a lot of data; the typical bottleneck in performance is the file manager or object store. A common example is NFS / over a LAN /l.

Network Attached Storage Device (NAS)
Developed at CMU /c, a more intelligent peripheral (disk or tape drive) that does its own file management. The drives enforce (but do not define) a security policy. Clients have an NFS /-like interface and access model.

Network Data Management Protocol (NDMP)
An open protocol for network-based backup of data.

Network File System (NFS)
Allows file systems /f from one machine to be shared transparently across a network by other machines. Originally defined in RFC 1094 (v2) ftp://ftp.isi.edu/in-notes/rfc1094.txt and RFC 1813 (v2) ftp://ftp.isi.edu/in-notes/rfc1813.txt.

Network Information Center (NIC)
Originally there was only one, located at SRI International and tasked to serve the ARAPNET (and later DDN) community. Today, there are many NICs operated by local, regional, and national networks all over the world. Such centers provide user assistance, document service, training, and much more.

Network Information Center (NIC)
The Internet's Network Information Center is responsible for controlling domain /d names across the entire Internet.

Network Information Service (NIS)
Formerly known as Yellow Pages (YP). A service used for the administration of network-wide databases within a specified domain /d. The databases, called maps, are provided by servers /s (master /m servers which control the domain and are client /c-writable for changes, and/or slave /s servers which are client /c-read-only) to participating hosts (clients) within a specified domain.

Network Interface Card (NIC)
Physical device that connect computers and other network equipment to the transmission medium used. When installed in a computer’s expansion bus slot, a NIC allows the computers to become a workstation on the network.

Network Layer
The layer of the OSI model that creates a communication path between two computers via routed packets. Transport protocols implement both the network layer and the Transport layer of the OSI stack. IP is a Network layer service.

Network Monitoring System (NMS)
An application to notify front-line support personnel about problems with applications running on remote machines (such as the trading floor machines).

Network News Transfer Protocol (NNTP)
A client/server protocol ftp://ftp.isi.edu/in-notes/rfc977.txt for exchanging and reading USENET news /u articles.

Network Operating System (NOS)
The software that runs on a file server and offers file, print, and other services to client workstations. Windows NT server 4 is an NOS. Other examples include NetWare. Banyan VINES, and IBM LAN server.

Network Time Protocol (NTP)
A protocol for synchronizing the clocks on all the hosts on a network or subnet to that of a single master time-keeper. Defined in RFC 1119 ftp://ftp.isi.edu/in-notes/rfc1119.txt (v2) and RFC 1305 ftp://ftp.isi.edu/in-notes/rfc1305.txt (v3).

Network-to-Network Interface (NNI)
The connection on telecommunications equipment between two disparate telecommunications networks.

NeuDL Neural network
Neural-network Description Language from the University of Alabama - . /NeuDL

Neural
net See Neural network Neural-network

Neural network
A computing device which converts one or more input signals to one or more output signals by means of an interconnected set of elementary non-linear signal processors called neurons. Animal brains are examples of biological neural networks. Artificial Neural Networks are man-made computing devices modelled after their biological counterparts. The features which distinguish artificial neural networks from traditional Von Neumann (sequential) computers are: (a) the elementary processors are highly non-linear (in the limit, they are simple threshold discriminators), (b) the neurons are highly interconnencted which allows a high degree of parallelism and (c) there is no idle memory containing data and programs, but rather each neuron is pre-programmed and continuously active - . /Neural

Neuron
See Neural network Neural-network, also McCulloch-Pitts McCulloch-Pitts

NEWBIE
A term used to describe someone who is new. New to the Internet, or new to a particular aspect of the internet.

NeWS
Network extensible Window System from Sun Microsystems, offering facilities similar to those of the X Window System X-Window-System. Communication is based on PostScript PostScript, and server functions can be extended.

NEWSGROUPS
A general name given to a vast collection of public access bulletin boards.

NewWave
A graphical user interface and object-oriented object-oriented environment from Hewlett-Packard, based on Windows Windows and available on UNIX UNIX workstations.

NEXT Near End Crosstalk:
Equipment that must concurrently receive on one wire pair and transmit on another wire pair in the same cable bundle must accommodate NEXT interference. NEXT is the portion of the transmitted signal that leaks into the receive pair. Since at this point on the link the transmitted signal is at maximum and the receive signal has been attenuated, it may be difficult to maintain an acceptable ACR with the received signal if the cable media allows large amounts of crosstalk leakage to occur. Foiled or shielded cables generally have less crosstalk than unshielded varieties.

NeXTMail
The application for reading and sending mail on NeXT computers. Can include attachments in messages using drag-and-drop. See also attachment /a, Multipurpose Internet Mail Extensions (MIME) /m, mail /m.

NeXTstep
A graphical interface builder, object-oriented application builder, and windowing software for the NeXT and IBM AIX systems.

NeXTstep
An extremely cool GUI that runs on NeXT machines.

NFF
Neutral File Format. A minimal scene description language - . /Graphics

NFS (Network File System)
A distributed file system developed by Sun Microsystems which allows a set of computers to cooperatively access each other’s files in a transparent manner.

NFS Network File System.
A network system that lets you treat files on another computer in more or less the same way you treat files on your own computer.

NFS Network File System:
developed by Sun to allow a computer to access files over a network as if they were on local disks; now public domain, a de facto standard.

NFT
Network File Transfer. An INTERLINK INTERLINK command.

Nial Nested Interactive Array Language.
A high-level array-oriented procedural language based on a mathematical theory of arrays, developed at Queen's University. It combines APL APL data structure ideas with LISP LISP-style evaluation concepts and a conventional control structure syntax

NIAM
Natural Language (or Nijssen) Information Analysis Method: a method for data modelling. (see "Conceptual Scheme and Relational Database Design", Nijssen and Halpin, Prentice-Hall, 1989)

NIC (Network Information Center)
NIC is, 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.

NIH
The US National Institutes of Health - . gopher://gopher.nih.gov

NIHCL
A class library Class-libraryfor C++ C++from the NIH NIH- . /NIHCL

NII
National Information Infrastructure (USA) - . /DIIG

NIS Network Information System
A database containing the user names, machine names, and directory names NFS use to give consistent names on all machines on a network.

NIS+
An extension to the Network Information Service (NIS) / including hierarchical domains, incremental updates to other servers, multiple indices to database tables, and built-in security. Requires the Solaris operating system.

N-ISDN Narrowband Integrated Services Digital Network:
Services include basic rate interface (2B+D or BRI) and primary rate interface (30B+D - Europe and 23B+D - North America or PRI). Supports narrowband speeds at/or below 1.5 Mbps.

NISO National Information Standards Organisation (USA).
NISO Standards cover many aspects of library science, publishing, and information services, and address the application of both traditional and new technologies to information services - . /NISO

NIST
National Institute of Standards and Technology, USA (formerly NBS)

NITF
National Imagery Transmission Format - . /Graphics

NLP
Natural Language Processing.

NLS
Native Language System: a set of interfaces specified by X/Open X/Open for developing applications to run in different natural language environments.

NLSP
See Novell Link State Protocol (NLSP) /.

NLSR
Natural Language Software Registry. A summary of the capabilities and sources of language processing software available to researchers

NM Network Management Entity:
The body of software in a switching system that provides the ability to manage the PNNI protocol. NM interacts with the PNNI protocol through the MIB.

NMF
Network Management Forum of OSI OSI

NML Network Management Layer:
An abstraction of the functions provided by systems which manage network elements on a collective basis, so as to monitor and control the network end-to-end.

NMS
Environment A set of NMS which cooperate to manage one or more subnetworks.

NMS Network Management System:
An entity that implements functions at the Network Management Layer. It may also include Element Management Layer functions. A Network Management System may manage one or more other Network Management Systems.

NMS
See Network Monitoring System (NMS) /.

NNI Network Node Interface:
An interface between ATM switches defined as the interface between two network nodes.

NNTP - Network News Transfer Protocol.
The server you connect to for newsgroups would be your NNTP server. Named Pipes An interprocess communication mechanism that is implemented as a file system service, allowing programming to be to run on it without using a proprietary application programming interface. Named pipes were developed to support more robust client/server communications than those allowed by the simpler NetBIOS.

Nodal Attribute
A nodal state parameter that is considered individually to determine whether a given node is acceptable and/or desirable for carrying a given connection.

Nodal
Constraint A restriction on the use of nodes for path selection for a specific connection.

Nodal Metric
A nodal parameter that requires the values of the parameter for all nodes along a given path to be combined to determine whether the path is acceptable and/or desirable for carrying a given connection.

Nodal
State Parameter Information that captures an aspect or property of a node.

Node In TCP/IP
an IP addressable computer systems, such as workstation, servers, minicomputers, mainframes, and routers. In IPX networks, the terms is usually applied to nonserver devices: workstation and printers.

Node
see Hypertext Hypertext

Node
Synonymous with logical node.

Normal form
A relation relation in a relational database relational-database is said to be in normal form if it satisfies certain constraints. Codd's original work defined three such forms.

NoteCards
An ambitious hypertext hypertext system developed at Xerox PARC, "designed to support the task of transforming a chaotic collection of unrelated thoughts into an integrated, orderly interpretation of ideas and their interconnections".

Notice
A message concerning some operation or change in the distributed system.

Novell
A proprietary local area network protocol developed by Novell Netware for the interconnection of PC PCs over Ethernet Ethernet.

Novell Link State Protocol (NLSP)
The equivalent of Open Shortest Path First (OSPF) /o for IPX /i RIP /r and SAP services. Much more efficient in its use of bandwidth and improved stability.

Novell
netware A network system that works on PCs, Macs, and Unix.

NOWEB
A system of structured programming and documentation from M.Speh in DESY. See Literate Programming Literate-Programming

NPC Network Parameter Control:
Network Parameter Control is defined as the set of actions taken by the network to monitor and control traffic from the NNI. Its main purpose is to protect network resources from malicious as well as unintentional misbehavior which can affect the QoS of other already established connections by detecting violations of negotiated parameters and taking appropriate actions. Refer to UPC.

NQIC
National Quality Information Centre of the IQA IQA systems.

NQS
Batch processing software for UNIX UNIX systems.

NREN
National Research and Education Network (USA) - . ftp://nic.merit.edu/nren/

Nrm
An ABR service parameter, Nrm is the maximum number of cells a source may send for each forward RM-cell.

NS
record See DNS record types, NS record /d.

NSAI
National Stsndards Authority of Ireland.

NSAP
NETSCAPE COMMERCE AND ENTERPRISE SERVER

NSAP Network Service Access Point:
OSI generic standard for a network address consisting of 20 octets. ATM has specified E.164 for public network addressing and the NSAP address structure for private network addresses.

NSE Network Software Environment:
a proprietary CASE framework CASE-framework from Sun Microsystems.

NSF
National Science Foundation (USA)

NSR
Non-Source Routed: Frame forwarding through a mechanism other than Source Route Bridging.

NSRD National Software Reuse Directory.
A directory of reusable software in the ASSET ASSET system, now incorporated in the Asset Reuse Library.

NT Network Termination:
Network Termination represents the termination point of a Virtual Channel, Virtual Path, or Virtual Path/Virtual Channel at the UNI.

NTFS
See Windows NT File System (NTFS) /w.

NTIS
National Technical Information Service of the US Department of Commerce.

NTP NETWORK TIME PROTOCOL
( protocol used to synchronize time between computers on Internet)

NTP Network Time Protocol:
a protocol built on top of TCP/IP TCP/IP that allows local clocks to be synchronised with reference clocks on the Internet Internet.

NTP
See Network Time Protocol (NTP) /.

NTSC National Television System Committee:
An industry group that defines how television signals are encoded and transmitted in the US.

Nu Thena
A software vendor specialising in rapid prototyping tools for real-time hardware and software systems, collaborating with DAZIX DAZIX.

Nucleus
The interior reference point of a logical node in the PNNI complex node representation.

NURBS
Non-Uniform Rational B-Splines, a technique used in CAD CAD etc. - . /NURBS

Nx64K
This refers to a circuit bandwidth or speed provided by the aggregation of nx64 kbps channels (where n= integer 1). The 64K or DS0 channel is the basic rate provided by the T Carrier systems.