A code that has n significant conditions, where n is a positive integer greater than
1.
Note 1: The integer substituted for n indicates the specific number of significant conditions, i.e., quantization states, in the code. For example, an 8-ary code has eight significant conditions and can convey three bits per code symbol.
Note 2: A prefix that indicates an… (Read More →)

See n-ary code.

An active element in the n-th layer of the Open Systems Interconnection--Reference Model (OSI-RM) that (a) interacts directly with elements, i.e., entities, of the layer immediately above or below the n-th layer, (b) is defined by a unique set of rules, i.e., syntax, and information formats, including data and control formats, and (c) performs a defined set of functions.
Note… (Read More →)

A defined action performed by an n-entity.
Note: An n-function may be (a) a single action, i.e., a primitive function, or (b) a set of actions.

A pseudorandom binary sequence of n bits that (a) is the output of a linear shift register and (b) has the property that, if the shift register is set to any nonzero state and then cycled, a pseudorandom binary sequence of a maximum of n = 2m-1 bits will be generated, where m is the number of stages, i.e., the… (Read More →)

A code in which the signals or groups of digits that represent coded items, such as characters, have the same number of signal elements or digits, namely n elements or digits, where n may be any positive integer.
Note: An example of an n-unit code is the 7-unit code (8-unit with parity) ASCII code. Each character is represented by a… (Read More →)

In the ISO Open Systems Interconnection--Reference Model (OSI--RM), an n+1 entity that uses the services of the n-layer, and below, to communicate with another n+1 entity.
Note: If n identifies a specific or a reference level, the n+1 layer is the layer above the n layer and the n-1 layer is the layer below the n layer. Thus, the n+2… (Read More →)

Network Access Configuration Function - Functional Entity

Network Access Control Function

1. Negative-Acknowledge Character,
2. Negative Acknowledgement.

Deprecated term. See dedicated circuit, permanent virtual circuit.

Acronym for negative-acknowledge character.

In communications security systems, a security penetration technique that makes use of the negative-acknowledge transmission-control character and capitalizes on a potential weakness in a system that handles asynchronous transmission interruption in such a manner that the system is in an unprotected state against unauthorized access during certain periods. [From Weik '89]

With respect to Internet addressing, an entity responsible for the allocation of names.
Note: Such naming is typically hierarchical, so that the authority to allocate domain names is restricted to a particular level within a domain, such as ". com", ". net", or ". gov".

North American Number Plan

Consists of the United States, Canada and the Caribbean countries: Anguilla, Antigua, Bahamas, Barbados, Bermuda, British Virgin Islands, Canada, Cayman Islands, Dominica, Dominican Republic, Grenada, Jamaica, Montserrat, St. Kitts & Nevis, St. Lucia, St. Vincent & Grenadines, Turks & Caicos Islands, Trinidad & Tobago, and U. S. Caribbean territories (including American Samoa, Puerto Rico, the U. S. Virgin Islands, Guam… (Read More →)

North American Number Plan Administration

NANPA holds overall responsibility for the neutral administration of NANP numbering resources, subject to directives from regulatory authorities in the countries that share the NANP. NANPA's responsibilities include assignment of NANP resources, and, in the U. S. and its territories, coordination of area code relief planning and collection of utilization and forecast data.

Network Address Port Translation

North American Region normally equated to the Caribbean, Canada, and the USA

Traffic consisting of plain or encrypted messages written in a natural language and transmitted in accordance with standard formats and procedures.
Note: Examples of narrative traffic include (a) messages that are placed on paper tape and transmitted via a teletypewriter (TTY), and on reception, are converted back to a printed page on another teletypewriter or teleprinter and (b) messages printed… (Read More →)

A modem whose modulated output signal has an essential frequency spectrum that is limited to that which can be wholly contained within, and faithfully transmitted through, a voice channel with a nominal 4-kHz bandwidth.
Note: High frequency (HF) modems are limited to operation over a voice channel with a nominal 3-kHz bandwidth.

In narrowband radio, the nominal 3-kHz bandwidth allocated for single channel radio that provides a transmission path for analog and quasi-analog signals.

Any analog signal or analog representation of a digital signal whose essential spectral content is limited to that which can be contained within a voice channel of nominal 4-kHz bandwidth.
Note: Narrowband radio uses a voice channel with a nominal 3-kHz bandwidth.

National Advanced Spectrum and Communications Test Network (NIST)

1. Network Address Translation,
2. Network Address Translator.

Network Address Translation - Protocol Translator

Abbreviation for North American Telecommunications Association.

1. National Communications System (NCS) was initially established by President Kennedy in August
196
3.  Executive Order 12472 formally established the role of the NCSto assist the President, the National Security Council, the Director of the Office of Science and Technology Policy, and the Director of the Office of Management and Budget, in the discharge of their national security emergency… (Read More →)

The joint telecommunications industry/Federal Government operation established by the National Communications System to assist in the initiation, coordination, restoration, and reconstitution of National Security or Emergency Preparedness (NS/EP) telecommunications services or facilities.

A standard that governs the use of electrical wire, cable, and fixtures, and electrical and optical communications cable installed in buildings.
Note: The NEC was developed by the NEC Committee of the American National Standards Institute (ANSI), was sponsored by the National Fire Protection Association (NFPA), and is identified by the description ANSI/NFPA 70-xxxX, the last four digits representing the… (Read More →)

A database that utilizes MAC addresses and Bluetooth beacon public device addresses to identify a Dispatchable Location for nearby wireless devices for a CMRS provider’s coverage footprint.

A database that utilizes MAC addresses and Bluetooth beacon public device addresses to identify a Dispatchable Location for nearby wireless devices for a CMRS provider’s coverage footprint.

NENA is a professional non-profit organization, established to promote implementation and awareness of 9-1-1 as the U. S. and Canadian universal emergency number. NENA provides a forum for dialogue between and among public safety and industry partners. NENA serves its members through policy advocacy, establishment of technical and operational standards, certification programs and a broad spectrum of educational offerings.

NECA or the National Exchange Carrier Association administers the FCC’s Access Charge Plan. Administration of the plan includes but is not limited to the filing of access charge tariffs with the FCC, the collection and validation of cost and revenue data and the processing of FCC Regulatory fees. Access charges are the fees long distance companies pay to access the… (Read More →)

NECA Tariff FCC No.4 is an SP’s legal billing authority for interstate access service charges. Tariff No.4 is the database that SPs reference for interconnection information that supports the ordering, billing and provisioning of interstate access services in North America. Tariff No.4 also contains information that describes the location and technical capabilities of the SPs’ wire centers which provide interstate… (Read More →)

A proposed, advanced, seamless web of public and private communications networks, interactive services, interoperable hardware and software, computers, databases, and consumer electronics to put vast amounts of information at users' fingertips.
Note: NII includes more than just the physical facilities (more than the cameras, scanners, keyboards, telephones, fax machines, computers, switches, compact disks, video and audio tape, cable, wire, satellites,… (Read More →)

The number identifying a calling user line within an area designated by a country code. [T1.104-1991]

A digit or combination of digits to be dialed by a calling subscriber, making a call to a subscriber in his own country but outside his own numbering area. It provides access to the automatic outgoing trunk equipment. [CCITT E.160] [T
1. Rpt30-1994]

NS/EP is the acronym for National Security and Emergency Preparedness. NS/EP communications are survivable, resilient, enduring, and effective communications services that are used to maintain a state of readiness or to respond to and manage any event or crisis (local, national, or international) that causes or could cause injury or harm to the population, damage to or loss of property,… (Read More →)

Information that has been determined, pursuant to Executive Order 12958 or any predecessor order, to require protection against unauthorized disclosure. [INFOSEC-99]

Any telecommunications or information system operated by the United States Government, the function, operation, or use of which: (a) involves intelligence activities; (b) involves cryptologic activities related to national security; (c) involves command and control of military forces; (d) involves equipment that is an integral part of a weapon or weapon system; or (e) is critical to the direct fulfillment… (Read More →)

See NTSC standard.

Of an antenna, the lowest frequency at which the antenna resonates without the addition of any inductance or capacitance.

A unit of distance used in navigation and based on the length of one minute of arc taken along a great circle.
Note 1: Because the Earth is not a perfect sphere, various values have been assigned to the nautical mile. The value 1852 meters (607
6. 1 ft. ) has been adopted internationally.
Note 2: The nautical mile is… (Read More →)

To move around (a) within a series of Web pages, or (b) among different Web pages, by following hyperlinked paths within each document. Synonyms browsing, surfing [slang].

Synonym droid.

Synonym droid.

Abbreviation for network busy hour. See busy hour.

Abbreviation for narrowband radio voice frequency.

A call disposition category for a call attempt that does not find an available outgoing trunk. [T1.209-1998]

Abbreviation for National Coordinating Center for Telecommunications.

Abbreviation for network channel interface code. An encoded representation used to identify 5 interface elements located at a point of termination (POT) at central office or customer location. The interface elements are: total conductors, protocol, impedance, protocol options, and transmission level points. [T1.223-1991]

1. National Communications System,
2. net control station.

See Network Channel Code

(NC is a registered trademark of iconectiv, LLC. )

A condition of an interface, as determined by the network, based on the network's capability to terminate another call to that interface. The interface is said to be NDUB if any of the following conditions exist: (a) if the maximum number of information channels available has been reached and the network does not support the offering of additional calls beyond… (Read More →)

Network Element

Network Element to Operations System

A central office or similar facility's ability to maintain continuity of operations without any operationally significant interruption of service from either hardware or software failures in the presence of one or more HEMP (high-altitude electromagnetic pulse) events. [T1.320-1994]

Synonym near-field region.

1. Pertaining to the delay introduced, by automated data processing, between the occurrence of an event and the use of the processed data, e.g., for display or feedback and control purposes.
Note 1: For example, a near-real-time display depicts an event or situation as it existed at the current time less the processing time.
Note 2: The distinction between near… (Read More →)

Synonym near-field region.

Crosstalk that is propagated in a disturbed channel in the direction opposite to the direction of propagation of a signal in the disturbing channel.
Note: The terminals of the disturbed channel, at which the near-end crosstalk is present, and the energized terminal of the disturbing channel, are usually near each other.

The diffraction pattern of an electromagnetic wave, which pattern is observed close to a source or aperture, as distinguished from a far-field diffraction pattern.
Note: The pattern in the output plane is called the near-field radiation pattern. Synonym Fresnel diffraction pattern.

1. The close-in region of an antenna wherein the angular field distribution is dependent upon distance from the antenna. Synonyms near field, near zone.
2. In optical fiber communications, the region close to a source or aperture.
Note: The diffraction pattern in this region typically differs significantly from that observed at infinity and varies with distance from the source.

A technique for measuring the refractive-index profile of an optical fiber by using an extended source to illuminate an endface and measuring the point-by-point radiance at the exit face.

In radio propagation, a wave that is reflected from the ionosphere at a nearly vertical angle and that is used in short-range communications to reduce the area of the skip zone and thereby improve reception beyond the limits of the ground wave.

Abbreviation for National Electric Code®.

1. For a given class of emission, the width of the frequency band which is just sufficient to ensure the transmission of information at the rate and with the quality required under specified conditions. [NTIA] [RR]
Note: Emissions useful for the adequate functioning of the receiving equipment, e.g., the emission corresponding to the carrier of reduced carrier systems, must be… (Read More →)

1. The legitimate requirement of a person or organization to know, access, or possess sensitive or classified information that is critical to the performance of an authorized, assigned mission.
2. The necessity for access to, or knowledge or possession of, specific information required to carry out official duties. [INFOSEC-99] See also Least Privilege.

Deprecated synonym for inverter.

See feedback.

Synonym de-stuffing.

Synonym de-stuffing.

A transmission control character sent by a station as a negative response to the station with which the connection has been set up.
Note 1: In binary synchronous communication protocol, the NAK is used to indicate that an error was detected in the previously received block and that the receiver is ready to accept retransmission of that block.
Note 2:… (Read More →)

National Emergency Numbering Association

Abbreviation for noise equivalent power.

1. A unit used to express ratios, such as gain, loss, and relative values.
Note 1: The neper is analogous to the decibel, except that the Naperian base
2. 71828182
8. . . is used in computing the ratio in nepers.
Note 2: The value in nepers, Np, is given by Np = ln(x1/x2), where x1 and x2 are the… (Read More →)

A command menu within another command menu. See command menu.

Synonym communications net.

Abbreviation for network browser.

1. A radio station that performs net control functions, such as controlling traffic and enforcing operational discipline. [From Weik '89]
2. [A] terminal in a secure telecommunications net responsible for distributing key in electronic form to the members of the net. [NIS]

The overall gain of a transmission circuit.
Note 1: Net gain is measured by applying a test signal at an appropriate power level (see Note 5) at the input port of a circuit and measuring the power delivered at the output port. The net gain in dB is calculated by taking 10 times the logarithm of the ratio of the… (Read More →)

The overall loss of a transmission circuit.

The maximum change in net loss occurring in a specified portion of a communication system during a specified period.

The operation of an organization of stations capable of direct communication on a common channel or frequency.
Note: Net operations (a) allow participants to conduct ordered conferences among participants who usually have common information needs or related functions to perform, (b) are characterized by adherence to standard formats and procedures, and (c) are responsive to a common supervisory station, called… (Read More →)

An interface between a single-channel radio station (usually in a radio net) and switched communications systems.

[Slang] A contraction of network etiquette. The written or unwritten rules of etiquette that govern online interaction between users on the Internet.
Note: Some typical rules are a ban on profane or offensive language, a requirement to respect other users, and a ban on floods of unsolicited advertisements. Netiquette rules may be enforced by a moderator or may be self-policed… (Read More →)

Abbreviation for Nationwide Emergency Telecommunications Service. See Government Emergency Telecommunications Service.

1. An interconnection of three or more communicating entities.
2. An interconnection of usually passive electronic components that performs a specific function (which is usually limited in scope), e.g., to simulate a transmission line or to perform a mathematical function such as integration or differentiation.
Note: A network may be part of a larger circuit.

A physical entity that provides network access for users. It contains the call-control agent function and may include the call-control function. [T1.667-1999]

The signaling point code, containing for U. S. national networks, the network identification, network cluster, and network cluster member fields (24 bits). [T1.110-1987]

Wherever the carrier places the home router, they typically request the IP addresses in the home not be represented directly to the network. Instead, a transplant NAT is used.

A group of network management functions that (a) provide support services, (b) ensure that the network is used efficiently, and (c) ensure prescribed service-quality objectives are met.
Note: Network administration may include activities such as network address assignment, assignment of routing protocols and routing table configuration, and directory service configuration.

1. The design principles, physical configuration, functional organization, operational procedures, and data formats used as the bases for the design, construction, modification, and operation of a communications network.
2. The structure of an existing communications network, including the physical configuration, facilities, operational structure, operational procedures, and the data formats in use.

Network Attachment is the process by which a network entity (such as the ITF or DNG) establishes Layer 3 connectivity to an IP-network and obtains network configuration data.

The probability a network can perform its required functions. [T
1. Rpt24-1993]

A computer program for browsing hyperlinked documents (especially on the Web).
Note 1: A network browser formats and displays information so obtained in a form useful to the viewer.
Note 2: A network browser may function in a graphical mode or in a text-only mode.

See busy hour.

An encoded representation used to identify both switched and non-switched channel services. Included in this code set are customer options associated with individual channel services, or feature groups and other switched services.

(NC is a registered trademark of iconectiv, LLC. )

An encoded representation used to identify interface elements located at a Point Of Termination (POT), which may also be known as a Point of Interface (POI).

(NCI is a registered trademark of iconectiv, LLC. )

The field in the U. S. signaling point code structure that identifies groups of signaling points and individual STPs (signaling transfer points) of a signaling network. [T1.110-1987]

1. Synonym thin client.
2. Any computer connected to a network.

The topological description of a network that specifies, in terms of circuit termination locations and quantities, the interconnection of the transmission nodes.

In a switch or network node, software designed to store and forward frames between nodes.
Note: An NCP may be used in local area networks or larger networks.

The ability to deliver consistent services from an IP infrastructure across a diversity of access networks. The IP infrastructure also supports session and policy control, applications and service capability, and Operations, Administration, Maintenance and Provisioning (OAM&P). While network convergence is not necessary for service convergence it can simplify its implementation.

Data that are specific to the functionality of the network. [T1.667-1999]

In integrated services digital networks, a piece of telecommunications equipment that provides support or services to the user.

A functional block that communicates with a telecommunications management network (TMN) for the purpose of being monitored, or controlled, or both. [T1.210-1993]

A building (such as a central office) or nonbuilding location housing NEs. Communication within an NE location may be accomplished with minimal attention to such factors as noise, lightning protection, or the cost of bandwidth; communication outside an NE location uses suitable modems and uses conventional communications services or an EOC (embedded operations channel). [T1.204-1992]

1. In telephony, the discipline concerned with (a) determining internetworking service requirements for switched networks, and (b) developing and implementing hardware and software to meet them.
2. In computer science, the discipline of hardware and software engineering to accomplish the design goals of a computer network.
3. In radio communications, the discipline concerned with developing network topologies.

See netiquette.

The connection between the radio port controller and the PCS (personal communications services) switching center. [T
1. Rpt34-1994]

A complete or partial failure of a component or components of a network because of malfunction or natural or human-caused disasters. Partial failures include degradation (and graceful degradation). [T
1. Rpt24-1993]

A combination of the network's unservability (U), duration (D), and extent (E) parameters that exceeds a threshold. [After T
1. Rpt24-1993]

See NFS.

The field in the U. S. signaling point code structure that identifies signaling networks. [T1.110-1987]

A failure (hardware, software, human, or process) of a telecommunications network component that prevents call completion.

Information within the service information octet of the message signal unit that permits discrimination between national and international messages. [T1.226-1992]

See NIC.

See network survivability.

1. The point of interconnection between a user terminal and a private or public network.
2. The point of interconnection between the public switched network and a privately owned terminal.
Note: Code of Federal Regulations, Title 47, part 68, stipulates the interface parameters.
3. The point of interconnection between one network and another network.
4. The point of demarcation between… (Read More →)

See NIC.

1. A device that performs interface functions, such as code conversion, protocol conversion, and buffering, required for communications to and from a network.
2. A device used primarily within a local area network (LAN) to allow a number of independent devices, with varying protocols, to communicate with each other.
Note 1: An NID converts each device protocol into a common… (Read More →)

Synonym network interface device.

Cooperation among networks in the processing, management, and creation of services that span multiple networks. [After T1.667-1999]

Synonym direct inward dialing.

See Open Systems Interconnection--Reference Model.

A function within the network layer by means of which one correspondent network entity forwards data to another correspondent network entity. [T1.204-1992]

Loss added to the network to control echo. [T1.508-1998]

1. The execution of the set of functions required for controlling, planning, allocating, deploying, coordinating, and monitoring the resources of a telecommunications network, including performing functions such as initial network planning, frequency allocation, predetermined traffic routing to support load balancing, cryptographic key distribution authorization, configuration management, fault management, security management, performance management, and accounting management.
Note: Network management does not… (Read More →)

In network management, the entity that initiates requests for management information from managed systems or receives spontaneous management-related notifications from managed systems.

A Network Modification is any type of planned equipment, software, trunk or facility activity which has the potential to significantly affect interconnected networks (e. g. rearrangement of existing network elements, switch homing rearrangements, SS7 rehoming).

A grouping of one or more network elements (at one or more sites) which provides network related functions, and is administered as a single entity. A single site may contain more than one network node. For the purpose of this glossary, a network node is considered synonymous with a network element, and is usually at a single site. This restriction… (Read More →)

An identification number, within a computer network or set of interconnected networks, that uniquely identifies a computer.
Note: Under the Internet protocol system, the network number forms a part of the IP address of each computer in the network. [2382-pt.35]

Software that (a) controls a network and its message (e.g., packet) traffic, and queues, (b) controls access by multiple users to network resources such as files, and (c) provides for certain administrative functions, including security.
Note 1: A network operating system is most frequently used with local area networks and wide area networks, but could also have application to larger… (Read More →)

A centralized organization responsible for the operation and maintenance of its network. [2382-pt.35]

The operator responsible for the development, provision and maintenance of real-time networking services and for operating the corresponding networks. [After T1.667-1999]

A call state in which the network transmits the caller's emergency service ID (CESID) to the public service answering point (PSAP) customer installation (CI). [T1.414-1998]

Synonym direct outward dialing.

The qualitative level at which a network fulfills its function. [After T
1. Rpt24-1993]

An ISDN number, supplied by the calling user's or the redirecting user's network, which is associated with the calling user or the redirecting user. It is possible that the NPN may have the same value as the user provided number (UPN) especially in cases where delivery of two calling party numbers is supported. The NPN may also be accompanied by… (Read More →)

1. The organization that maintains and operates the network components required for intelligent network (IN) functionality. A network provider may also take more than one role, e.g., also acting as service provider.
2. The entity connecting customers and Service Providers. The delivery system usually is composed of access networks and core or backbone networks, using a variety of network technologies.… (Read More →)

See network survivability.

Automatic or manual methods to return a network to its normal function in response to a network failure. [T
1. Rpt24-1993]

The network components that provide a virtual connection between two circuit sections. A network section may be either an access network section or a transit network section. [T1.504-1989]

Protection of networks and their services from unauthorized modification, destruction, or disclosure. It provides assurance the network performs its critical functions correctly and there are no harmful side-effects. [INFOSEC-99]

[A] subset of network architecture specifically addressing security-relevant issues. [INFOSEC-99]

The combination of the MTP (message transfer part) and the SCCP (signaling connection control part). [T1.110-1987]

The side of the network interface or the network functions as seen from the interface. [T1.601-1988]

A specific location where there are one or more ICT equipment entities, facility terminations, nodal locations, or administrative operations, e. g. building

A process concerned with surveillance of the network as a whole. It includes activities for coordination and assigning priorities to maintenance actions. The information necessary to support this process comes from alarms, measurements, and indicators of operational (including congestion) status. [T1.226-1992]

The (a) ability of a network to maintain or restore an acceptable level of performance during network failures by applying various restoration techniques, and (b) mitigation or prevention of service outages from network failures by applying preventive techniques. [T
1. Rpt24-1993]

The analytical processes for estimating how well network services will be affected and restored with transparencies to the users as a result of a failure.

In the ITU-T International X.121 format, the sets of digits that comprise the complete address of the data terminal end point.
Note: For an NTN that is not part of a national integrated numbering format, the NTN is the 10 digits of the ITU-T X.25 14-digit address that follow the Data Network Identification Code (DNIC). When part of a national… (Read More →)

Synonym for demarcation point.

Network equipment that provides functions necessary for network operation of ISDN access protocols.
Note: Network termination provides functions essential for transmission services.

In Integrated Services Digital Networks (ISDN), a functional grouping of customer-premises equipment that includes functions that may be regarded as belonging to OSI Layer 1, i.e., functions associated with ISDN electrical and physical terminations on the user premises.
Note: The NT1 forms a boundary to the network and may be controlled by the provider of the ISDN services.

In Integrated Services Digital Networks (ISDN), an intelligent device that may include functionality for OSI Layers 1 through 3 (dependent on individual systems requirements).

The specific physical, i.e., real, or logical, i.e., virtual, arrangement of the elements of a network.
Note 1: Two networks have the same topology if the connection configuration is the same, although the networks may differ in physical interconnections, distances between nodes, transmission rates, and/or signal types.
Note 2: The common types of network topology are illustrated [refer to the… (Read More →)

[The] totality of protection mechanisms within a network, including hardware, firmware, and software, the combination of which is responsible for enforcing a security policy. [INFOSEC-99]

An internetwork administrative signaling mechanism in the call control procedure between packet switching public data networks.

1. In computer security, a penetration technique in which different communication networks are used to gain access to a data processing system to avoid detection and trace-back. [After 2382-pt.8]
2. [A] penetration technique in which different communication networks are linked to access an information system (IS) to avoid detection and trace-back. [INFOSEC-99]

In a computer networking environment, an application (program) that is centrally stored, e.g., on a server, and copies of which may be accessed on demand by a client and used temporarily (i.e., for a single session) by the client (e.g., a desktop computer).
Note: Multiple clients may make simultaneous use of a given network-launched application.

1. In ac power distribution, the conductor that (a) is intentionally grounded on the supply side of the service disconnect and (b) provides a current return path for ac power currents.
2. In three-phase ac "Y," i.e., wye, power distribution, the low-potential fourth wire that conducts only that current required to achieve electrical balance, i.e., to provide a return path… (Read More →)

A telegraph system in which (a) current flows during marking intervals and no current flows during spacing intervals for the transmission of signals over a line, and (b) the direction of current flow is immaterial. Synonyms single-current system, single-current transmission system, single-Morse system.

An intentional ground applied to the neutral conductor or neutral point of a circuit, transformer, machine, apparatus, or system.

A method of teletypewriter operation in which marking signals are formed by current pulses of one polarity, either positive or negative, and spacing signals are formed by reducing the current to zero or nearly zero.

A relay in which the direction of movement of the armature does not depend upon the direction of the current in the circuit controlling the armature.

All customer premises equipment not in service or in the inventory of a regulated telephone utility as of December 31, 1982.

“Newly acquired numbers“ are those that have been activated within the LERG Routing Guide, and thus are available for assignment, within the preceding 90 days of reporting utilization. Newly acquired numbering resources may be excluded from the calculation of utilization level (FCC CFR
5
2. 15(g)(3)(ii)

Synonym newsreader.

A server on a network that stores, organizes, and distributes messages for selected newsgroups. [2382-pt.35]

Information distributed by a computer, e.g., one operated by an Internet service provider that maintains current articles within selected groups.

Synonym forum.

A local software application (client program) that provides access by means of which a user may view one or more forums or newsgroups from one or more news servers.
Note: Most newsreaders format and display information from the server in a form suitable to the user. Synonym news client. [After 2382-pt.35]

An IP-based system comprised of managed IP-based networks (ESInets), functional elements (applications), and databases that replicate traditional E9-1-1 features and functions, and provide additional capabilities. NG9-1-1 is designed to provide access to emergency services from all connected communications sources, and provide multimedia data capabilities for PSAPs and other emergency service organizations.

A Next Generation Network (NGN) is a packet-based network able to provide services including Telecommunication Services and able to make use of multiple broadband, QoS-enabled transport technologies and in which service-related functions are independent from underlying transport-related technologies. It offers unrestricted access by users to different service providers. It supports generalized mobility which will allow consistent and ubiquitous provision of… (Read More →)

Abbreviation for noise figure.

1. Abbreviation for network file system.
1. A file system that is distributed over a computer network.
2. A file system, on a single computer, that contains the low-level networking files for an entire network. [2382-pt.35]

Next Generation

40-Gigabit-capable Passive Optical Network 2

Next Generation Network

Next Generation Network Service Provider

Non Governmental Organization

1. Next Generation Operation Support System,
2. Next Generation Operations Systems Software.

Next Generation Service Network

Network Interface

Part of a byte, usually half of a byte. [Obsolete]

1. Abbreviation for network interface card. A network interface device (NID) in the form of a circuit card that is installed in an expansion slot of a computer to provide network access.
Note: Examples of NICs are cards that interface a computer with an Ethernet LAN and cards that interface a computer with an FDDI ring network.
2. Abbreviation for… (Read More →)

New Intercarrier Communication Process

Acronym for network interface device, network inward dialing.

Abbreviation for National Information Infrastructure.

A telephone service via which the caller may access information on a charge-per-call or charge-per-time basis.

National Institute of Standards and Technology

Abbreviation for network interface unit. See network interface device.

Network Interface Unit/Network Interface Device

New Local Service Provider

Navigational Message Authentication

A security-violating, network-scanning tool that can scan a network using a variety of protocols, can operate in stealth mode, and can automatically identify remote operating systems.

Abbreviation for nautical mile.

Network Management Layer

Network Management System

Network-to-Network Interface

New Network Service Provider

Abbreviation for network news transfer protocol. An application protocol that provides the means to transfer files for computer conferences. [After 2382-pt.35]

A call-disposition category for a call attempt that does not find an available outgoing trunk. [T1.207-1998]

An SIT (special information tone) classification for call attempts that fail to find an available long distance service provider outgoing trunk. [T1.207-1998]

An SIT (special information tone) classification for call attempts that fail to find an available Local Service Provider outgoing trunk. [T1.207-1998]

[An] Area, room, or space that, when staffed, must be occupied by two or more appropriately cleared individuals who remain within sight of each other. [INFOSEC-99]

Network Operations Center

Acronym for network outward dialing.

The principal clock or alternate clock located at a particular node that provides the timing reference for all major functions at that node.

Synonym node.

1. In network topology, a terminal of any branch of a network or an interconnection common to two or more branches of a network. Synonyms junction point, nodal point.
2. In a switched network, one of the switches forming the network backbone.
Note: A node may also include patching and control facilities.
3. A technical control facility (TCF).
4. A… (Read More →)

1. An undesired disturbance within the frequency band of interest; the summation of unwanted or disturbing energy introduced into a communications system from man-made and natural sources.
2. A disturbance that affects a signal and that may distort the information carried by the signal.
3. Random variations of one or more characteristics of any entity such as voltage, current, or… (Read More →)

1. Interfering and unwanted electrical currents in a device or system.
2. In optical communications, the rms component of the optical detector output electrical current with no incoming signal present.

At a given data-signaling rate or modulation frequency, operating wavelength, and effective noise bandwidth, the radiant power that produces a signal-to-noise ratio of unity at the output of a given optical detector.
Note 1: Some manufacturers and authors define NEP as the minimum detectable power per square root bandwidth. When defined this way, NEP has the units of watts per… (Read More →)

Synonym noise figure.

An indication of the level of background noise that the terminating end-point may play out in the absence of packets. [T1.312-1991]

Of an active device, over the bandwidth of interest, the contribution by the device itself to thermal noise at its output. The noise figure is usually expressed in decibels (dB), and is with respect to thermal noise power at the system impedance, at a standard noise temperature (usually 20o C, 293 K) over the bandwidth of interest. It is determined… (Read More →)

The noise power, usually relative to a reference.
Note: Noise level is usually measured in dB for relative power or picowatts for absolute power. A suffix is added to denote a particular reference base or specific qualities of the measurement. Examples of noise-level measurement units are dBa, dBa(F1A), dBa(HA1), dBa0, dBm, dBm(psoph), dBm0, dBm0P, dBrn, dBrnC, dBrn(f1-f2), dBrn(144-line), pW, pWp,… (Read More →)

1. The power generated by a random electromagnetic process.
2. Interfering and unwanted power in an electrical device or system.
3. In the acceptance testing of radio transmitters, the mean power supplied to the antenna transmission line by a radio transmitter when loaded with noise having a Gaussian amplitude-vs. -frequency distribution.

The noise power in a bandwidth of 1 Hz, i.e., the noise power per hertz at a point in a noise spectrum.
Note: The noise-power density of the internal noise that is contributed by a receiving system to an incoming signal is expressed as the product of Boltzmann's constant, k, and the equivalent noise temperature, Tn. Thus, the noise-power density… (Read More →)

1. Reduction of the noise power level in electrical circuits.
2. The process of automatically reducing the noise output of a receiver during periods when no carrier is being received.

At a pair of terminals, the temperature of a passive system having an available noise power per unit bandwidth at a specified frequency equal to that of the actual terminals of a network.
Note: The noise temperature of a simple resistor is the actual temperature of that resistor. The noise temperature of a diode may be many times the actual… (Read More →)

1. Interfering and unwanted voltage in an electronic device or system.
2. In optical communications, the rms component of the optical detector output electrical voltage with no incoming signal present.

A specific amplitude-vs. -frequency characteristic that permits a measuring set to give numerical readings that approximate the interfering effects to any listener using a particular class of telephone instrument.
Note 1: Noise weighting measurements are made in lines terminated either by the measuring set or the class of instrument.
Note 2: The most widely used noise weightings were established by… (Read More →)

A notch, i.e., a dip, in the noise frequency spectrum characteristic of a device, such as a transmitter, receiver, channel, or amplifier, from external sources or internal sources.
Note: The noise window is usually represented as a band of lower amplitude noise in a wider band of higher amplitude noise. [From Weik '89]

1. In facsimile or display systems, such as television, a nonuniformity in the black area of the image, i.e., document or picture, caused by the presence of noise in the received signal.
2. A signal or signal level that is supposed to represent a black area on the object, but has a noise content sufficient to cause the creation of… (Read More →)

1. In facsimile or display systems, such as television, a nonuniformity in the white area of the image, i.e.,, document or picture, caused by the presence of noise in the received signal.
2. A signal or signal level that is supposed to represent a white area on the object, but has a noise content sufficient to cause the creation of… (Read More →)

The widest band of frequencies, inclusive of guard bands, assigned to a channel.
Note: Nominal bandwidth should not be confused with the terms "necessary bandwidth," "occupied bandwidth,"or "rf bandwidth. "

The rate at which stuffing bits are inserted when both the input and output bit rates are at their nominal values.

In facsimile systems, the average separation between centers of adjacent scanning or recording lines.

Signaling that is independent of an end-to-end bearer connection, including support for the functions of registration, authentication, and validation.

In personal communications service (PCS), terminal access to a network in which there is no set relationship between a terminal and the access interface.
Note: The access interface and the terminal each has its own separate "identifiers. " The terminal may be moved from one access interface to another while maintaining the terminal's unique identity. [After T1.244-1995]

See active video frame identification.

A code in which "1s" are represented by one significant condition and "0s" are represented by another, with no neutral or rest condition, such as a zero amplitude in amplitude modulation (AM), zero phase shift in phase-shift keying (PSK), or mid-frequency in frequency-shift keying (FSK).
Note: For a given data signaling rate, i.e., bit rate, the NRZ code requires only… (Read More →)

A code in which "1s" are represented by a change in a significant condition and "0s" are represented by no change.

A binary encoding scheme in which a signal parameter, such as electric current or voltage, undergoes a change in a significant condition or level every time that a "one" occurs, but when a "zero" occurs, it remains the same, i.e., no transition occurs.
Note 1: The transitions could also occur only when "zeros" occur and not when "ones" occur. If… (Read More →)

Synonym non-return-to-zero mark.

A binary encoding scheme in which a signal parameter, such as electric current or voltage, undergoes a change in a significant condition or level every time that a "zero" occurs, but when a "one" occurs, it remains the same, i.e., no transition occurs.
Note 1: The transitions could also occur only when "ones" occur and not when "zeros" occur. If… (Read More →)

Non-terrestrial networks (NTN) are networks or segments of networks that use either Uncrewed Aircraft Systems (UAS) operating typically between 8 and 50km altitudes, including High Altitude Platforms (HAPs) or satellites in different constellations to carry a transmission equipment relay node or a base station.

A loopback in which the signal transmitted beyond the loopback point (the forward signal) when the loopback is activated, is not the same as the received signal at the loopback point. The forward signal may be a defined signal or unspecified. [T1.216-1998]

A form of common-channel signaling where the signaling channel serves one or more trunk groups, at least one of which terminates at a point other than the signal transfer point at which the signaling channel terminates.

The signaling mode in which messages involving two (nonadjacent) signaling points are communicated between them over two or more signaling links in tandem passing through one or more signaling transfer points other than those which are the origin and destination of the messages. [T1.226-1992]

A switch that has enough paths across it that an originated call can always reach an available line without encountering a busy condition.

In cryptography, a time-variant parameter, such as a counter or a time stamp, that is used in key management protocols to prevent message replay and other types of attacks. [After X9.42]

Operation that uses a control discipline for multipoint data communication links in which transmission may be between tributary stations or between the control station and tributary stations.

Synonym ovality.

Office that is not yet equipped or incapable of being equipped, for provision of originating and terminating Feature Group D LATA access service.

Synonym automatic remote rekeying.

Of the total technical load at a facility during normal operation, the part that is not required for synchronous operation.

Synonym read-only memory.

Distortion caused by a deviation from a linear relationship between specified input and output parameters of a system or component.

Direct conversion of a photon from one wavelength to one or more other wavelengths.
Note 1: In an optical fiber, nonlinear scattering is usually not important below the threshold irradiance for stimulated nonlinear scattering.
Note 2: Examples of nonlinear scattering are Raman and Brillouin scattering.

A twisted pair that has no intentionally added inductance.

Administrative, support, and housing power requirements. Synonym utility load.

1. The capability, in security systems, that guarantees that a message or data can be proven to have originated from a specific person.
2. Assurance the sender of data is provided with proof of delivery and the recipient is provided with proof of the sender's identity, so neither can later deny having processed the data. [INFOSEC-99]
3. The property of… (Read More →)

Synonym aperiodic antenna.

Synonym public key cryptography.

Synonym dispersion-unshifted fiber.

A data transmission channel in which separate timing information is not transferred between the data terminal equipment (DTE) and the data circuit terminating equipment (DCE).

Synonym asynchronous network.

See asynchronous transmission.

The term "Nonsynchronous Test Line" denotes an arrangement in step-by-step end offices which provides operational tests which are not as complete as those provided by the synchronous test lines, but can be made more rapidly.

See asynchronous transmission.

Of the total operational load at a facility during normal operation, the part used for support purposes, such as general lighting, heating, air-conditioning, and ventilating equipment.

A mode of operating a data transmission system in which control characters are treated and interpreted as such, rather than simply as data or text bits in a bit. [From Weik '89]

NACK-Oriented Reliable Multicast

A state that exists on a permanent virtual circuit connection when there are no alarm conditions on either the originating or terminating endpoints. The absence of alarms must be satisfied on both the channelized side and the packetized side. During the NORM state, signaling packets have their normal alarm (N/A) bit set to
0. [T1.312-1991]

The mode of ACSE (association control service element) operation that results in the transfer of ACSE semantics, using the presentation service. [T1.208-1989]

The mode of operation of the Presentation Layer, which provides the full facilities of the presentation service. [T1.208-1989]

A still image transmitted in the ANSI Tl.314 video stream encoded to the same resolution as the previous motion video (i.e., QCIF—quarter common intermediate format).
Note: This mode uses a bit 2 "document camera indicator. " [T1.80
0. 08-1995]

The routing of a given signaling traffic stream under normal conditions (in the absence of failures). [T1.226-1992]

A bit used in signaling packets to transfer information on alarm status across a permanent virtual circuit in the direction of transmission from the channelized side to the packetized side. The N/A bit set to 0 indicates normal operation. The N/A bit set to 1 indicates the existence of an alarm on the channelized access facility or error condition on… (Read More →)

1. In an optical fiber, a dimensionless quantity, V, given by where a is the core radius, is the wavelength in vacuum, n1 is the maximum refractive index of the core, and n2 is the refractive index of the homogeneous cladding.
Note 1: In multimode operation of an optical fiber having a power-law refractive index profile, the approximate number of… (Read More →)

A plan for the allocation of unique 10-digit address numbers. The numbers consists of a 3-digit area (numbering plan area) code, a 3-digit office code, and a 4-digit line number. The plan also extends to format variations (e.g., 3-digit and 7-digit address), prefixes (e.g., 1, 0, 01, and 011), and special code applications (e.g., service access codes). [T1.104-1988]

The organization that is responsible for administering the North American Numbering Plan (NANP).

The NANPA gathers forecast and utilization information to monitor and project exhaust in individual NPAs/area codes as well as in the NANP overall. This semi-annual report includes number utilization information as well as a five-year forecast of demand by year. Pooling carriers report at the thousands-block level per rate center. Non-pooling carriers report at the Central Office Code level per… (Read More →)

At the data terminal equipment/data circuit-terminating equipment (DTE/DCE) interface, a steady-state condition that indicates that the DCE is not ready to accept a call-request signal or that the DTE is not ready to accept an incoming call.

1. A method of changing a key-enciphering key so as to confirm the identities of the originator and the ultimate recipient. [After X9.8]
2. The registration of data with a trusted third party that allows the later assurance of the accuracy of its characteristics such as content, origin, time and delivery [7498-2].

In a relatively wide band of frequencies, not necessarily of uniform amplitude, a narrow band of frequencies having relatively low amplitudes.

Synonym band-stop filter.

Noise from which a narrow band of frequencies has been removed.
Note: Notched noise is usually used for testing devices or circuits.

Abbreviation for neper.

Abbreviation for numbering plan area.

NPA code relief refers to an activity that must be performed when and NPA nears exhaust of its 792 NXX capacity. Options for relief are described in Section
6. 0 of the NPA Code Relief Planning & Notification Guidelines.

The date by which the NPA is introduced and routing of normal commercial traffic begins.

Number Portability Administration Center

Abbreviation for net radio interface.

Abbreviation for non-return-to-zero.

Synonym non-return-to-zero mark.

NS/EP NGN Priority Services (NS/EP NGN-PS) are the evolution of Legacy circuit-switched GETS and WPS to achieve service continuity in the packet-switched NGN and leverage the NGN to offer new features and priority multimedia services.

1. The NSA is the official cryptologic organization of the U. S. government. need-to-know:
1. Security principle that the dissemination of classified information should be no wider than is required for the efficient conduct of the business in hand and restricted to those who are authorized to have access [CESG].
2. Access right granted in accordance with this principle [CESG].… (Read More →)

The high-speed national network that superseded ARPA Net as the framework of the Internet.
Note: NSFnet was created under the auspices of the National Science Foundation. [After Bahorsky]

1. Network Service Provider
2. New Service Provider

Abbreviation for network terminating interface.

Abbreviation for network terminal number.

1. Network Termination Point
2. Network Time Protocol

National Television Systems Committee

Abbreviation for National Television Standards Committee standard. The North American standard (525-line interlaced raster-scanned video) for the generation, transmission, and reception of television signals.
Note 1: In the NTSC standard, picture information is transmitted in vestigial-sideband AM and sound information is transmitted in FM.
Note 2: In addition to North America, the NTSC standard is used in Central America, a… (Read More →)

1. An expression of the extent to which the performance of a system, facility, or device is expected to degrade in a given nuclear environment.
2. The physical attributes of a system or component that will allow survival in an environment that includes nuclear radiation and electromagnetic impulses (EMI).
Note 1: Nuclear hardness may be expressed in terms of either… (Read More →)

In an antenna radiation pattern, a zone in which the effective radiated power is at a minimum relative to the maximum effective radiated power of the main beam.
Note 1: A null often has a narrow directivity angle compared to that of the main beam. Thus, the null is useful for several purposes, such as radio navigation and suppression of… (Read More →)

In transmission systems, a control character (a) that is used to accomplish media-fill stuffing or a time-fill stuffing in storage device or in a data transmission line and (b) that may be inserted and removed from a series of characters without affecting the meaning of the series.
Note: The null character may affect the control of equipment or the format… (Read More →)

The Number Portability Administration Centers (NPACs) are the registries that enable consumers and businesses in the U. S. and Canada to maintain their telephone numbers when they change service providers. The US NPAC contains routing information on ported TNs and pooled blocks and facilitates the updating of the routing databases of all subtending SPs in the portability area. The Canadian… (Read More →)

1. A defined geographic area identified by a unique three-digit code used in the North American Number Plan Area. [T1.207-1998] [T1.209-1998]
Note 1: Defined geographic area could mean the entire area encompassed by the North American Numbering Plan Area (for 800, 888, 877 codes, etc. ).
Note 2: By virtue of the overlay concept deployed in some states, there may… (Read More →)

1. The sine of the vertex angle of the largest cone of meridional rays that can enter or leave an optical system or element, multiplied by the refractive index of the medium in which the vertex of the cone is located.
Note: The NA is generally measured with respect to an object or image point and will vary as that… (Read More →)

A loss of optical power that occurs at a splice or a pair of mated connectors when the numerical aperture of the "transmitting" fiber exceeds that of the "receiving" fiber, even if the cores are precisely the same diameter and are perfectly aligned. [FAA]
Note 1: The higher numerical aperture of the transmitting fiber means that it emits a larger… (Read More →)

Abbreviation for near-vertical-incidence skywave.

1. In the North American direct distance dialing numbering plan, a central office code of three digits that designates a particular central office or a given 10,000-line unit of subscriber lines; "N" is any number from 2 to 9, and "X" is any number from 0 to
9.
2. The three digits (in positions 4, 5, and 6) in an… (Read More →)

The maximum time interval between equally spaced samples of a signal that will enable the signal waveform to be completely determined.
Note 1: The Nyquist interval is equal to the reciprocal of twice the highest frequency component of the sampled signal.
Note 2: In practice, when analog signals are sampled for the purpose of digital transmission or other processing, the… (Read More →)

The reciprocal of the Nyquist interval, i.e., the minimum theoretical sampling rate that fully describes a given signal, i.e., enables its faithful reconstruction from the samples.
Note: The actual sampling rate required to reconstruct the original signal will be somewhat higher than the Nyquist rate, because of quantization errors introduced by the sampling process.

A theorem, developed by H. Nyquist, which states that an analog signal waveform may be uniquely reconstructed, without error, from samples taken at equal time intervals. The sampling rate must be equal to, or greater than, twice the highest frequency component in the analog signal. Synonym sampling theorem.