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    Tele-Communication (Telecom) Terms Glossary and Dictionary - N

    NAA: Next Available Agent

    Next Available Agent (NAA) is a scheme for selecting an agent to handle a call. The strategy seeks to maintain an equal load across skill groups or services.

    Naked Call

    Naked Call refers to an incoming call that receives no greeting message and no call menus/flexible routing before it is routed into an ACD (Automatic Call Distribution) queues.

    Naked DSL

    Naked DSL is a digital subscriber line without a PSTN (Public Switched Telephone Network) service. In other words, only a standalone DSL internet service is provided on the local loop. In regular DSL, a wire runs from the telephone switch to a POTS (Plain Old Telephone Service) splitter. The POTS splitter separates the DSL and voice bands and then a wire carrying both services runs from the splitter to the cable head, where it continues on to the customer on an outside plant. But Naked DSL the portion of cable from the switch to the POTS splitter is removed, therefore removing dial tone from the line.

    NANP: North American Numbering Plan

    North American Numbering Plan (NANP) is the North American telephone number arrangement or the process for assigning 10-digit (3+3+4) North American telephone numbers, NPA-NXX-XXXX. NPA is the Area Codes, NXX is the Exchanges and XXXX is the Line Numbers.

    National Access Fee

    National Access Fee is a Federal tax placed upon telecommunication services provided by telephone companies.

    National Information Infrastructure

    National Information Infrastructure is the foundation that supports the Information Superhighway by setting national standards that make networks and appliances compatible.

    NATO Phonetic Alphabet

    NATO phonetic alphabet is a common name for the international radiotelephony spelling alphabet which assigns code words to the letters of the English alphabet so that critical combinations of letters (and numbers) can be pronounced and understood by those who transmit and receive voice messages by radio or telephone regardless of their native language, especially when the safety of navigation or persons is essential. It is used by many national and international organizations. It is a subset of the much older International Code of Signals (INTERCO), which originally included visual signals by flags or flashing light, sound signals by whistle, siren, foghorn, or bell, as well as one, two, or three letter codes for many phrases. The same alphabetic code words are used by all agencies, but each agency chooses one of two different sets of numeric code words. NATO uses the normal English numeric words (Zero, One, with some alternative pronunciations), whereas the IMO uses compound numeric words (Nadazero, Unaone). The name NATO phonetic alphabet became widespread because the signals used to facilitate the naval communications and tactics of the United States and NATO have become global.

    NCAS: Non-Call Associated Signaling

    Non-Call Associated Signaling (NCAS) is a signaling that is independent of an end-to-end bearer connection, including support for the functions of registration, authentication, and validation

    NCP: Network Control Point

    Network Control Point (NCP) may have different meanings depending on the context. 1) In IBM SNA, it refers to a host-generated network control program ( ran on an IBM 3704, 3705 or 3745) that controls the operation of a communications controller. 2) In Virtual Private Network (VPN), it is a centralized database that stores a subscriber's unique VPN definition. Highly sophisticated, this database screens every call and applies call processing control in accordance with customer-defined requirements. 3) Within the AT&T signaling network, NCP is the process that sends routing requests to a Customer Routing Point (CRP).

    NCT: Network Control and Timing

    Network Control and Timing (NCT) is a control link between a switching module (SM) and the communications module (CM) in a Lucent 5ESS switching system.

    NEBS Level 1

    "NEBS Level 1", the lowest level of NEBS standard developed by Bell Labs for RBOC central office equipment, addresses the personnel and equipment safety requirements of GR-63-CORE and GR-1089-CORE. This is useful for getting prototypes into a lab trial. It's also a requirement that is imposed on Competitive Local Exchange Carriers (CLECs) in order for them to deploy equipment into an RBOC's network.

    NEBS Level 2

    "NEBS Level 2", the second level of NEBS standard developed by Bell Labs for RBOC central office equipment, addresses equipment operability, but in a controlled environment. For example, equipment could be used in a data center, however, if the equipment performs non-critical operations it could be used under environmental extremes. Note that this level is very rarely used because it is ambiguous.

    NEBS Level 3

    "NEBS Level 3", the highest level of NEBS standard developed by Bell Labs for RBOC central office equipment, means the equipment is ready to be installed in the carier class operational network for the long haul. The equipment will operate under the environmental extremes found in a central office. In a nutshell, the equipment meets all of the requirements of GR-63-CORE and GR-1089-CORE.

    NEBS: Network Equipment Building Systems

    Network Equipment Building Systems (NEBS) is the Bellcore requirement for equipment deployed in a central office environment of PSTN in North America. NEBS covers spatial, hardware, crafts person interface, thermal, fire resistance, handling and transportation, earthquake and vibration, airborne contaminants, grounding, acoustical noise, illumination, EMC, and ESD requirements.

    Negative-acknowledge character

    Negative-acknowledge character is a transmission control character sent by a station as a negative response to the station with which the connection has been set up.

    Network Convergence

    Network convergence refers to using packet network to conduct voice (telephony), video and data services, and phasing out the traditional circuit switched PSTN (Public-Switched Telephone Network) gradually. The migration process from two separate data and voice to finally a complete converged packet network carrying both voice and data services may take decades to finish. The driving forces behind such migration are cost saving, operation efficiency and new services deployment.

    Network Element Function Block

    Network Element Function Block is a functional block that communicates with a telecommunications management network (TMN) for the purpose of being monitored, or controlled, or both.

    Network Indicator

    Network Indicator (NI) is the Sub-Service Field in the Signalling Information Octet (SIO) of the message signal unit that permits discrimination between national and international messages, when NI is: 0 = international, 1 = reserved, 2= national, and 3 = national spare.

    Network Management Center

    Network Management Center is the location where large or public telephone networks are supervised, monitored and preserved.

    Network Services

    Network Services, in a telecommunication network, are specified sets of information transfer capabilities furnished to users between telecommunications network points of termination. Network services categories include access and transport, public and private, and switched and non-switched.

    NEXT: Near-End Crosstalk

    Near-End Crosstalk (NEXT) is an error condition that can occur when connectors are attached to twisted pair cabling. NEXT is usually caused by crossed or crushed wire pairs. The error condition does not require that the wires be crushed so much that the conductors inside become exposed. Two conductors only need to be close enough so that the radiating signal from one of the wires can interfere with the signal traveling on the other. Most medium- to high-end cable testers are capable of testing for NEXT errors.

    NGN: Next Generation Network

    Next Generation Network (NGN) is a broad term for an integrated network that will offer voice, data, video services over both wireline and wireless infrastructure. The technologies required for the NGN is evolving.

    Night Service

    Night Service is an telecommunication element that allows the lines ringing into a company to be handled differently during specific times of the day.

    N-ISDN: Narrowband ISDN

    Narrowband ISDN (N-ISDN) is the communication standards developed by the ITU-T for baseband networks. N-ISDN is based on 64-kbps B channels and 16- or 64-kbps D channels.

    NNX

    NNX refers to the first three numbers used in a North American local telephone number (NNX-NXX-XXXX) before the use of "1" in direct distance dialing. These numbers are now designated as NXX, allowing local central offices to have numbers that look like area codes.

    No Such Number Tone

    The No Such Number Tone is one of the audible tones in telephone system. It tells the calling party to hang up, check the called number, and dial again. In modern systems, calls to unassigned or discontinued numbers will also be routed to a machine announcement system, such as 6A or 7A, which verbally supplies the required message. In some older offices, you could be routed to an intercepting operator. In some offices, reorder tone is returned in this condition..

    No-Answer Transfer

    No-Answer Transfer is a telecommunication service feature (provided by some cellular carriers in combination with call-waiting) that automatically transfers an incoming cellular call to another phone number if the cellular subscriber is unable to answer.

    Noise-Like

    Noise-Like is a distortion or unwanted signal that usually is electromagnetic interference or ambient noise.

    Non-Associated Mode Signaling

    Non-associated Mode Signaling is one of many signaling schemes. In Non-associated Mode Signaling, signaling messages involving two non-adjacent signaling points are conveyed (between those signaling points) over two or more signaling links in tandem that passes through one or more STPs (Signaling Transfer Part).

    Non-Switched Line

    Non-Switched Line refers to: 1. a connection between computers or devices that do not have to be established by dialing. 2. a dedicated line.

    NPA Routing

    NPA Routing refers to the routing of calls based on the originating ANI (Automatic Number Identification) NPA (area code).

    NPA Split

    NPA Split refers to the telephone numbering scheme that subdivides an area code, with the creation of a new area code. This is necessary when the number of telephones in an area code (NPA) grows to an excessive number.

    NPA: Numbering Plan Area

    Numbering Plan Area (NPA) refers to North American "Area Codes." It is the first 3 digits of a phone number: 2-to-9, 0-to-9, 0-to-9.

    NPA-NXX Routing

    NPA-NXX Routing refers to Area Code / Exchange Routing. Route calls are based on the originating ANI NPA-NXX.

    NRZ: Non-Return-to-Zero

    Non-Return-to-Zero (NRZ) is a binary code in telecommunication system, 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 pulse amplitude modulation (PAM), zero phase shift in phase-shift keying (PSK), or mid-frequency in frequency-shift keying (FSK). The pulse has more energy than a RZ (Return-to-Zero) code, but it does not have arrest state, which means a synchronization signal must also be sent alongside the code.

    NRZI: Nonreturn to Zero Inverted

    Nonreturn to Zero Inverted (NRZI) is the signal that maintains constant voltage levels with no signal transitions (no return to a zero-voltage level) but interpret the presence of data at the beginning of a bit interval as a signal transition and the absence of data as no transition.

    NS/EP Telecommunications

    NS/EP telecommunications, short for National Security or Emergency Preparedness telecommunications of the US, are the tlecommunications services that are used to maintain a state readiness or to respond to and manage any event or crisis (it could be local, national, or even international) that causes or could cause injury or harm to the population, damage to or loss of property, or degrade or threaten the national security or emergency preparedness posture of the United States. NS/EP telecommunications in the United States are managed and controlled by the National Communications System using Telecommunications Service Priority through both the Government Emergency Telecommunications Service and Wireless Priority Service.

    NSAPI: Network Service Access Point Identifier

    Network Service Access Point Identifier (NSAPI) is an index to the PDP (Packet Data Protocol) context that is using the services provided by the lower layer (SNDCP (Sub Network Dependent Convergence Protocol)). One PDP may have several PDP contexts and Network Service Access Point Identifiers.

    NSP: Network Service Provider

    Network Service Provider(NSP) is a company which provides telecommunication services with their own or leased equipment.

    NT-1: Network Termination 1

    Network Termination 1 (NT-1) is a device based on ISDN that provides the interface between customer premise equipment and central office switching equipment.

    Null Modem

    Null modem is a communication method to connect two DTEs (computer, terminal, printer etc.) directly using a RS-232 serial cable. The original RS-232 standard only defined the connection of DTEs with DCEs i.e. modems. With a null modem connection the transmit and receive lines are crosslinked. Depending on the purpose, sometimes also one or more handshake lines are crosslinked. Several wiring layouts are in use because the null modem connection is not covered by a standard. Null modems are commonly used for file transfer between computers, or remote operation.

    Number Check Tone

    Number Checking Tone is a steady High Tone. It is sometimes used at DSA switchboards in No. 1 crossbar and some step-by-step areas to verify the verbal identification of the calling line. On some older systems, Number Checking Tone was a steady 135 Hz tone.

    NXX

    NXX refers to Exchanges in North American telephone numbering scheme that is the first 3 digits of a 7-digit phone number (2-to-9, 0-to-9, 0-to-9) and digits 4, 5 and 6 in a 10 digit NANP (North American Numbering Plan) telephone number - NPA-NXX-XXXX.