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Narrowband ISDN

N-ISDN was an attempt to replace the analog telephone system with a digital one. Unfortunately, the standardization process was too long and regarding to the technology progress in this area, once the standard was finally agreed, it was obsolete. ...

Net gain (telecommunications)

In telecommunications, net gain is the overall gain of a transmission circuit. Net gain is measured by applying a test signal at an appropriate power level at the input port of a circuit and measuring the power delivered at the output port. The n ...

Network-based Call Signaling

Network-based Call Signaling is a profile of the Media Gateway Control Protocol for use in PacketCable applications for voice-over-IP. A network implementing NCS is designed according to the media gateway control protocol architecture for interco ...

NS/EP telecommunications

NS/EP telecommunications is an abbreviation for National Security or Emergency Preparedness telecommunications of the United States. Telecommunications services that are used to maintain a state of readiness or to respond to and manage any event ...

Number translation service

A number translation service translates a dialled telephone number, typically beginning 08 in the UK to a geographical connect number beginning 01 or 02 in the UK. The connect number may be changed without changing the published dialled number. O ...

Open fiber control

In telecommunication, Open fiber control is a protocol to ensure that both ends of a fiber optic cable are connected before laser signals are transmitted in order to protect people from eye damage. When a device is turned on, it sends out low pow ...

Optical link

An optical link is a telecommunications link that consists of a single end-to-end optical circuit. A cable of optical fibers, possibly concatenated into a dark fiber link, is the simplest form of an optical link. Other forms of optical link can i ...

Out-of-band infrastructure

The concept of out-of-band infrastructure has been used throughout the telecom industry for voice communication since the mid-1950s. Having a critical requirement to always provide dial-tone for health and safety reasons, the telecom industry cre ...

Overhead information

Overhead information is digital information transferred across the functional interface between a user and a telecommunications system, or between functional units within a telecommunications system, for the purpose of directing or controlling th ...

Overmodulation

Overmodulation is the condition that prevails in telecommunication when the instantaneous level of the modulating signal exceeds the value necessary to produce 100% modulation of the carrier. In the sense of this definition, it is almost always c ...

Pacific Caribbean Cable System

Pacific Caribbean Cable System is an optical submarine communications cable. which connects the United States with several countries of the Caribbean. It was put into operation in September 2015. The cable runs from Florida to the east coast of P ...

Pacific Telegraph Act of 1860

The Pacific Telegraph Act of 1860 called for the facilitation of communication between the east and west coasts of the United States of America. Hiram Sibley of the Western Union Telegraph Company won the contract. In 1861, Benjamin Franklin Fick ...

Personal mobility

In Universal Personal Telecommunications, personal mobility is the ability of a user to access telecommunication services at any UPT terminal on the basis of a personal identifier, and the capability of the network to provide those services in ac ...

Phase inversion

Phase Inversion when referring to sound acoustics, is incorrect terminology and is sometimes used incorrectly interchangeably to mean Polarity inversion. Polarity Inversion is the swapping of the two poles of an alternating current source. A pola ...

The Phone Company

The Phone Company was a volunteer network providing a free email-to-fax service. It was one of the few grandfathered users of the.int top-level domain. The websites address was tpc.int. The address is no longer reachable. Archives in the Wayback ...

Plesiochronous system

In telecommunications, a plesiochronous system is one where different parts of the system are almost, but not quite, perfectly synchronised. According to ITU-T standards, a pair of signals are plesiochronous if their significant instants occur at ...

PocketDish

PocketDish was a discontinued line of media receivers for use with the Dish Network satellite television service. Using a Dish Network DVR receiver, PocketDish users could download television shows and other recorded video content from the DVR on ...

Polarization-division multiple access

Polarization-division multiple access is a channel access method used in some cellular networks. Separate antennas are used in this type, each with different polarization and followed by separate receivers, allowing simultaneous regional access o ...

Power delay profile

The power delay profile gives the intensity of a signal received through a multipath channel as a function of time delay. The time delay is the difference in travel time between multipath arrivals. The abscissa is in units of time and the ordinat ...

Primary channel

In telecommunication, the term primary channel has the following meanings: In a communications network, the channel that has the highest data rate of all the channels sharing a common interface. The communication channel that is designated as a p ...

Private line

In telecommunication, a private line is typically a telephone company service that uses a dedicated, usually unswitched point-to-point circuit, but it may involve private switching arrangements, or predefined transmission physical or virtual path ...

Process gain

In a spread-spectrum system, the process gain is the ratio of the spread bandwidth to the unspread bandwidth. It is usually expressed in decibels. For example, if a 1 kHz signal is spread to 100 kHz, the process gain expressed as a numerical rati ...

Psophometer

In telecommunications, a psophometer is an instrument that measures the perceptible noise of a telephone circuit. The core of the meter is based on a true RMS voltmeter, which measures the level of the noise signal. This was used for the first ps ...

Psophometric weighting

Psophometric weighting refers to any weighting curve used in the measurement of noise. In the field of audio engineering it has a more specific meaning, referring to noise weightings used especially in measuring noise on telecommunications circui ...

Quadruplex telegraph

The Quadruplex telegraph is a type of electrical telegraph which allows a total of four separate signals to be transmitted and received on a single wire at the same time. Quadruplex telegraphy thus implements a form of multiplexing. The technolog ...

Qualcomm MSM Interface

The Qualcomm MSM Interface is a proprietary interface for interacting with Qualcomm baseband processors and is a replacement for the legacy cellular extensions of the Hayes command set. With mobile chipsets, communication between the application ...

QUICC

QUICC. The original QUICC was the 68k-based Motorola 68360. It was followed by the PowerPC-based PowerQUICC, PowerQUICC II, PowerQUICC II+ and PowerQUICC III. Early chips used a separate RISC engine to control the serial interfaces, enhancing per ...

Radio modem

Radio modems transfer data wirelessly across a range of up to tens of kilometres. Using radio modems is a modern way to create Private Radio Networks. Private radio networks are used in critical industrial applications, when real-time data commun ...

RANAP

In telecommunications networks, RANAP is a protocol specified by 3GPP in TS 25.413 and used in UMTS for signaling between the Core Network, which can be a MSC or SGSN, and the UTRAN. RANAP is carried over Iu-interface. RANAP signalling protocol r ...

ReadyLink

ReadyLink was a "walkie-talkie" service, which used Session Initiation Protocol, offered by the Sprint Nextel Corporation, in an effort to compete with then-separate Nextel Communications. It was necessary to have a Sanyo or a Samsung ReadyLink c ...

Received noise power

In telecommunications, received noise power is a measure of noise in a receiver. For example, the received noise power might be: The value of noise power, from all sources, measured at the line terminals of a telephone sets receiver. Either flat ...

Reference antenna

A reference antenna is an antenna with known performance. It is normally used to calibrate other systems. Reference antennas are built with particular care taken to make them simple, robust and repeatable. In a common usage scenario a reference a ...

Reflection loss

In telecommunications, reflection loss occurs on a line which results in part of the energy being reflected back to the source. This can occur: In an optical fiber, the loss that takes place at any discontinuity of refractive index, especially at ...

Relative transmission level

In telecommunication, relative transmission level is the ratio of the signal power, at a given point in a transmission system, to a reference signal power. The ratio is usually determined by applying a standard test tone at zero transmission leve ...

Removable User Identity Module

Removable User Identity Module is a card developed for cdmaOne/CDMA2000 handsets that extends the GSM SIM card to CDMA phones and networks. To work in CDMA networks, the R-UIM contains an early version of the CSIM application. The card also conta ...

Retrodirectivity

A retrodirective antenna is an antenna that transmits the signal back in the same direction it came from. This is based on the principle of self-phase conjugation of the input signal. Directivity depends on relative phases of signal radiated from ...

Return channel

In communications systems, the return channel is the transmission link from a user terminal to the central hub. Return links are often, but not always, slower than the corresponding forward links. Examples where this is true include asymmetric di ...

RIOJA-1

RIOJA-1 was a submarine telecommunications cable system linking the United Kingdom and Spain across the North Atlantic Ocean. It had landing points in: Virgen del Mar Beach, Santander, Spain Porthcurno, Cornwall, United Kingdom It was withdrawn f ...

RJK

RJK or Russia-Japan-Korea is a submarine telecommunications cable system linking the three named countries bordering the East Sea. It began operation in 1995. It has landing points in: Nakhodka, Russia Naoetsu, Japan Pusan, Korea It has a transmi ...

Route flapping

In computer networking and telecommunications, route flapping occurs when a router alternately advertises a destination network via one route then another in quick sequence. Route flapping is caused by pathological conditions within the network w ...

SAm-1

SAm-1 is an optical submarine communications cable. It started operations in 2000, connecting the United States, Puerto Rico, Brazil, Argentina, Chile, Peru and Guatemala. In 2007, SAm-1 was extended to reach Ecuador and Colombia. It has landing ...

Secondary frequency standard

In telecommunications, a secondary frequency standard is a frequency standard that does not have inherent accuracy, and therefore must be calibrated against a primary frequency standard. Secondary standards include crystal oscillators and rubidiu ...

Self-healing ring

A self-healing ring, or SHR, is a telecommunications term for loop network topology, a common configuration in telecommunications transmission systems. Like roadway and water distribution systems, a loop or ring is used to provide redundancy. SDH ...

Service control point

A service control point is a standard component of the Intelligent Network telephone system which is used to control the service. Standard SCPs in the telecom industry today are deployed using SS7, SIGTRAN or SIP technologies. The SCP queries the ...

Service data unit

In Open Systems Interconnection terminology, a service data unit is a unit of data that has been passed down from an OSI layer or sublayer to a lower layer. This unit of data has not yet been encapsulated into a protocol data unit by the lower la ...

Service-oriented provisioning

Service-oriented provisioning is a technology concept developed during the early 2000s to curb the hyper competition developing in the Wireless Internet service provider and ISP space. It refers to the capability of defining and working with "ser ...

Shared medium

In telecommunication, a shared medium is a medium or channel of information transfer that serves more than one user at the same time. Most channels only function correctly when one user is transmitting, so a channel access method is always in eff ...

Signaling protocol

A signaling protocol is a type of protocol used to identify signaling encapsulation. Signaling is used to identify the state of connection between telephones or VOIP terminals. The following is a list of signaling protocols: Q.931 Signaling Syste ...

Simple Loop Prevention Protocol

Simple Loop Prevention Protocol in computer networking is a Data Link Layer protocol developed by Nortel to protect against Layer 2 network loops. SLPP uses a small hello packet to detect network loops. The SLPP protocol checks packets from the o ...

Simplex communication

Simplex communication is a communication channel that sends information in one direction only. The International Telecommunication Union definition is a communications channel that operates in one direction at a time, but that may be reversible; ...