Glossary of Telecom Terms : I

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See Internet Access Provider.


See Interexchange Carrier.


IC Transit Connection
The connection between a Verizon access tandem and another service provider's switching entity/Point of Interface for the purpose of carrying the provider's traffic to and from an Interexchange Carrier.


See Institute of Electrical and Electronic Engineers.


See Intellilight Entrance Facility.


See Incumbent Local Exchange Carrier.


Impulse Noise
Any momentary occurrence of noise on a channel that significantly exceeds the normal noise peaks. Impulse noise is analyzed by counting the number of occurrences that exceed a threshold.


See Intelligent Network.


Incumbent Local Exchange Carrier (ILEC)
In the Telecommunications Act of 1996 with respect to an area, the Incumbent Local Exchange Carrier is defined as the Local Exchange Carrier that, on the date of enactment of the Act, provided telephone exchange service in that area; for example, Verizon.


Independent Telephone Company
A Local Exchange Carrier other than a Regional Bell Operating Company.


Information Technology Network Management
This Verizon group tests Network Data Mover (NDM) connectivity.


Initial/Additional Indicator
An indicator that identifies whether Local Calling Plan usage charges are billed at the Initial or Additional rate.


Inside Wiring
Telephone wiring on the customer's side of the rate demarcation point, the point located on the subscriber's side of the telephone company's protector or other device serving the same purpose. For residences, the protector is usually located at the point where the telephone lines enter the house.


Installation Status
A Verizon Wholesale local pre-order transaction that allows CLECs the ability to query the status of pending work request(s) associated with a Service Order number and Circuit ID. Learn more.


Institute of Electrical and Electronic Engineers
Professional organization that defines network standards.


Integrated Digital Loop Carrier
A subscriber loop carrier system that integrates within the switch, generally at a DS1, level, twenty-four local link (loop) voice-grade equivalent transmission paths combined into a 1.544 megabits per second digital signal.


Integrated Services Digital Network (ISDN)
A widely available high bandwidth switched network service providing end-to-end digital connectivity over standard phone lines for simultaneous transmission of voice and data. There are two levels of service:

  1. Basic Rate Interface-ISDN (BRI-ISDN)--provides for digital transmission of two 64 kbps bearer channels and one 16 kbps data and signaling channel (2B+D).
  2. Primary Rate Interface-ISDN (PRI-ISDN)--provides for digital transmission of twenty three (23) 64 kbps bearer channels and one (1) 64 kbps data and signaling channel (23 B+D).

Integrated Services Digital Network User Part
The part of SS7 that comprises the signaling functions necessary to provide voice and non-voice services in ISDN and pre-ISDN architectures.


Intelligent Network
A telecommunications network offering enhanced facilities such as freephone, premium rate information services, call distribution services (for example, according to the geographical origin of the call), alternate call billing (sometimes provided through the use of personal calling cards), and virtual private network services. The intelligence to support these facilities is provided through specialized network nodes and telecommunications switches.


IntelliLight Broadband Transport (IBT)
A SONET-based point-to-point service providing high bandwidth interfaces over shared SONET infrastructure facilities. Learn more.


IntelliLight Entrance Facility
A Verizon Wholesale Solution providing an entrance transport alternative using a shared SONET-based fiber ring. Learn more.


IntelliLight Optical Transport Service (IOTS)
An Optical Networking Solution using Wavelength Division Multiplexing technologies WDM. Learn more.


IntelliLight Shared Dual Path
A Private Line service with dual paths transported over multiple shared, self-healing SONET rings. Learn more.


IntelliLight Shared Single Path
A Private Line service which is provided using a shared network SONET infrastructure. Learn more.


IntelliMux Service
A service whereby customers can reconfigure a specific voice grade, DDS and/or individual channels within a High Capacity DS1 service connected at a digital cross-connect system.


As described in the Telecommunications Act of 1996 Interconnection refers to the connection of separate pieces of equipment or transmission facilities within, between or among networks. For example, Interconnection includes Collocation arrangements, entrance facilities, Mid-Span Fiber Meet arrangements, etc.


Interconnection Agreement
An agreement between Verizon and a Carrier that provides for interconnection, collocation, resale, network elements, and ancillary services between the parties. The Interconnection Agreement is entered into under the terms of Section 251 of the Telecommunications Act of 1996.


Interconnection Facility
The physical connection of equipment, transmission facilities, etc., within, between and among networks, for transmission and routing of exchange service and exchange access.


Interconnection Point
The physical point on the network where two parties interconnect. The interconnection point is the demarcation point between ownership of the transmission facility and the outside network.


Interexchange Carrier or Interexchange Common Carrier
A telecommunications service provider authorized by the FCC to provide interstate long distance communications services between LATAs, and authorized by the State to provide long distance communications services. An Interexchange Carrier provides, directly or indirectly, interLATA or intraLATA telephone toll services. May be an individual, partnership, association, joint-stock company, trust, governmental entity or corporation engaged for hire in interstate or foreign communication by wire or radio, between two or more exchanges. An Interexchange Carrier may be a customer of Verizon.


A connection between two systems or devices. In routing terminology, a network connection; also, the boundary between adjacent layers of the OSI reference model. In telephony, a shared boundary defined by common physical interconnection characteristics, signal characteristics and meanings of interchanged signals.


Unwanted electrical signals or noise causing degradation of reception on a communications circuit.


InterLATA Service
As defined in the Telecommunications Act of 1996, telecommunications between a point located in a Local Access and Transport Area (LATA) and a point located outside such area.


International Direct Distance Dialing
Automatic international long distance dialing capability.


An international network of networks, originally started for military purposes, that connects millions of users instantaneously through commonly-used protocols such as TCP/IP, HTTP, FTP, Gopher, etc. The widely-used World Wide Web is available through the Internet.


Internet Access
The connection which allows you to get on the Internet through an Internet Service Provider (ISP), of your choice. The type of connection you choose is based on a number of different factors, including cost and the communications system you have.


Internet Address
Also called an IP (Internet Protocol) address; a 32-bit address assigned to hosts using TCP/IP .The address is written as four octets separated with periods (dotted decimal format) that are made up of a network section, an optional subnet section and a host section.


Internet Protocol
Part of the TCP/IP family of protocols that tracks the outgoing address of nodes, routes outgoing messages and recognizes incoming messages.


Internet Service Provider
A vendor that provides direct access to the Internet, and services such as email. The user accesses the ISP by dialing up through a personal computer and modem, or through a dedicated line. Also known as an Internet Access Provider (IAP).


Interoffice Facility (IOF)
Interoffice Facility provides routing for CLECs by using multiple interoffice transmission paths over non-dedicated facilities.


The ability to operate software and exchange information in a large network made up of different kinds of LANs.


Interstate Telecommunications
Telecommunications that originate and terminate in different states, subject to oversight by the FCC and state regulatory commissions.


Interval Guide
Verizon East resource providing CLECs / Resellers and carriers with the established due dates for provisioning specific service types. Due dates are determined by multiple factors including service type, # of lines, and complexity of provisioning.


IntraLATA Service
According to the Telecommunications Act of 1996, Telecommunications services that originate and end within one Local Access and Transport Area (LATA).


Intrastate Communications
Telecommunications that originate and terminate in the same state, subject to oversight by a state regulatory commission as provided by the laws of the state involved.


Intrastate IntraLATA
Services between two points within the same LATA that are not used in connection with InterLATA channels.


Invoice Billing
A Verizon Wholesale Billing Service that allows a customer to prepackage billing records for placement on an End-User invoice.


See Interoffice Facility.


See IntelliLight Optical Transport Service.


IP Address
Internet Protocol address; a 32-bit address assigned to hosts using TCP/IP. The address is written as four octets separated with periods (dotted decimal format) that are made up of a network section, an optional subnet section and a host section. Also known as an Internet Address.


IP Port
A service element in the Internet Protocol Virtual Private Network (IP-VPN) tariff: a physical port on a router. Learn more.


A Verizon Wholesale connectionless, packet-based IP routing service that provides private connectivity between customer locations. Learn more.


See Integrated Services Digital Network.


ISDN User Part (ISUP)
A part of the SS7 protocol that defines call setup messages and call takedown messages.


See IntelliLight Shared Single Path.


See Internet Service Provider.



See IntelliLight Shared Single Path.


See ISDN User Part.


See Interexchange Carrier.



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