0

Zero transmission (test) level point

1394

An IEEE standard for fire wire protection on communications network security specifications in 1995, also know as IEEE P-1394

16-QAM

Sixteen-state quadrature amplitude modulation

64-QAM

Sixty four-state quadrature amplitude modulation

256-QAM

Two fifty six-state quadrature amplitude modulation

3P

Predictive, Proactive, and Preventive philosophy

2W

Two Wire

4W

Four Wire

AAL

ATM Adaptation Layer

AAL5

ATM Adaptation Layer 5

ABD

Average busy day

ABM

Asynchronous balanced mode

ABR

Available bit rates, answer bid ratio

ABS

Alternate Billing Services

AC

Access Conditions, Alternating Current, Access Customer, Air Condition, Area Code, Access Control/Controller

AC-3

Digital Audio Compression – 3 (Dolby Labs)

ACD

Automatic call distributor

ACF

Access control field, advanced communications functions

ACF/NCP

Advanced communications functions/network control program

ACIA

AIN/CLASS Inter-working Application

ACK

Acknowledgement

ACO

Alarm cut off

ACP

Adjacent Channel Power

ACR

Allowed cell rate

ACS

Access Control and Security

ACSE

Association Control Service Element

ACTV

Multi Channel Programmer

ADC

Analog to Digital Converter

ADCCP

Advanced data communications control procedures

ADI

Area of Dominant Influence

ADM

Add-Drop Multiplexor

ADPCM

Adaptive differential pulse code modulation

ADSI

Analog Display Services Interface

ADSL

Asymmetric Digital Subscriber Line

ADSU

ATM Data Service Unit

A/D

Analog to Digital converter

AEP

Apple Talk Echo Protocol

AES

Audio Engineering Society

AFC

Antenna for Communications, Automatic Frequency Control

AFT

Automatic Fine Tuning

AG

Administrative Gateway

AGC

Automatic Gain Control

AGE

Application Gateway Emulator

AH

Ampere-Hours

AHE

Analog Headend

AID

Application Identifier

AIM

Application Interface Module

AIN

Advanced Intelligent Network

AIS

Automatic indication signals

ALC

Automatic Level Control, ATM Link Controller

ALE

Automatic link establishment

ALTS

Association for Local Telecommunications Services

ALU

Arithmetic Logic Unit

AM

Amplitude Modulation

AMA

Automatic Message Accounting

AMD

American Micro Devices

AMADNS

Automatic Message Accounting Data Networking System

AMI

Automatic mark inversion, alternate mark inversion

AML

Amplitude-Modulated Microwave Links, actual measured loss

AMS

Alarms Management Subsystem, Advertisement Management System

AM-VSB

Amplitude Modulation - Vestigial Side Band

ANI

Automatic number identification

ANSI

American National Standards Institute

AOCR

Automatic out-of-chain reroute

AOR

Atlantic operating region

AP

Access Provider

APaRT

Automatic packet recognition/translation technology

APD

Avalanche photo diode

APDU

Application Protocol Data Unit

API

Applications Programming Interface

APL

Average picture level

APPC

Advanced program-to-program communication

APPN

Advanced peer-to-peer networking

ARA

Apple Talk Remote Access

ARCnet

Attached Resource Computer network

ARM

Asynchronous response mode

ARP

Address Resolution Protocol

ARQ

Automatic repeat request

ART

ATM Router Task

AS

Autonomous system

ASBR

Autonomous system boundary router

AS/LIDB

LIDB Administrative System

ASCII

American Standard Code for Information Interchange

ASE

Application Service Element

ASI

Asynchronous Serial Interface

ASIC

Application Specific Integrated Circuit

ASK

Amplitude Shifting Key

ASN

Abstract Syntax Notation

ASN.1

Abstract Syntax Notation One

ASR

Access Service Request, answer seizure ratio, automatic send-receive

AST

Advanced Screen Telephony, automatic spinning tree

ASTA

Advanced software technology and algorithms

ASTB

Advanced Set-Top Box

ASTM

American Society for Testing Materials

AT

Automatic Tandem, Application Table, access tandem

ATC

Analog Transmission Channel

ATD

Automatic transfer device

ATDE

Adaptive time domain equalizer

ATDM

Asynchronous time-division multiplexing

ATEL

Advanced Television Evaluation Laboratory

ATIS

Alliance for Telecommunications Industry Solutions

ATM

Asynchronous Transfer Mode

ATMM

ATM management

ATP

Apple Talk Transaction Protocol

ATR

Answer-to-Reset

ATSC

Advanced Television Systems Committee

ATTL

Advanced Television Test Center

ATU-R

Asymmetrical Termination Unit-Remote

ATV

The U.S. advanced television system

ATVEF

Advanced Television Enhancement Forum

AU

Administrative unit

AUC

Authentication Center

AUI

Attachment unit interface

AURP

Apple Talk Update-Based Routing Protocol

AUTODIN

Automatic digital network

AWG

American wire gauge

AWGN

Additive white Gaussian noise

AZ

Azimuth

B3ZS

Binary 3-zero substitution

B8ZS

Binary 8-zero substitution

BAF

Bellcore AMA Format

BaM

Variant of BM

BARF

Basic Access to Remote Files

BASS

Business Applications Support System

B/C

Broadcast

BCAM

Broadcast and Conditional Access Manager

BCC

Bellcore Client Company

BCD

Binary coded decimal

BCH

Bits per circuit hour

BCS

Broadcast Control Suite

BDT

Bulk Data Table

BECN

Backward Explicit Congestion Notification

BER

Basic Encoding Rules, Bit Error Rate

BFS

Broadcast File Server

BGP

Border Gateway Protocol

BHCA

Busy hour call attemps

BIB

Backward indicator bit

BIG

Broadband Integrated Gateway (MPEG-2 term)

BIGA

Bus Interface Gate Array

BIOS

Basic Input/Output System

BIP-8

Bit Interleaved parity-8

BIPM

Bureau International des Poids et Mesures

B-ISDN

Broadband integrated services digital network

BIST

Built in self test

BITES

Backward inter-working telephone events

BITNET

"Because it is time" Networking Service

BITS

Building-integer timing supply

BLSR

Bi-directional Line Switched Self Healing Ring

BM

Broadcast Manager, Bandwidth Manager

BM/G

Broadband Multiplexer/Gateway

BML

Business Management Layer

BMM

Broadcast Manager Module

BNN

Boundary network node

BO

Backed-Off

BOC

Bell Operating Company

BOM

Bill of Material

BOOTP

Bootstrap Protocol

BOOTTERM

Boot terminal

BOS

Billing Outputs Specifications

BOSS

Business Operations Support System

BPDU

Bridge Protocol Data Unit

BPF

Band-pass filter

BPI

Baseline Privacy Interface

BPS, bps

Bits per second.

BRI

Basic Rate Interface

BRID

Bandwidth Reservation Identifier

BPSK

Binary phase-shift keying

BSC

Base station controller, binary symmetric channel, binary synchronous communication

BSD

Berkeley Standard Distribution

BSLBF

Bit String (serial) – Leftmost Bit First

BSM

Broadcast Segment Manager

BSN

Backward sequence umber

BSP

Bell System Practices

BSS

Business Support System, Broadcast Satellite Service, base station sys.

BT

Bridged tap, burst tolerance

BTA

Basic Trade Area

BTS

Base transceiver station

BTSC

Broadcast Television Standards Committee

BTU

British thermal unit

BUS

Broadcast and unknown server

BW

Bandwidth

C/A

Coarse acquisition

CA

Conditional Access

CAA

Conditional Access Authority (Power Key)

CABS

Carrier Access Billing System

CAC

Carrier Access Code

CAD

Computer Aided Design

CAM

Conditional Access Management, Content Addressable Memory, or Computer Aided Manufacturing

CAMC

Conditional Access Management Controller

CAMCS

Conditional Access Management Controller Subsystem

CAP

Carrier-less Amplitude and Phase Modulation, Competitive Access Provider

CAQAM

Conditional Access Quadrature Amplitude Modulator

CARE

Customer Account Record Exchange

CARS

Community Antenna Radio Service

CAS

Conditional Access (Sub) System

CAT

Conditional Access Table

CAT-3

Category 3 type of UTP cabling

CATV

Community Antenna Television, Cable Television

CAU

Common Access User

CBC

Cipher Block Chaining

CBDS

Connectionless Broadband Data Service

CBIP

Channel Bank Interface Protocol, Common Backplane Interface Processor

CBMC

Channel Bank Management Processor

CBMUX

Channel Bank Multiplexer

CBR

Constant Bit Rate

CBS

Channel Band System

CBT

Channel Band Test

CBTR

Carrier (recovery)-bit timing recovery (TDM)

CBX

Computer-based branch exchange

CCG

Computer clock generator

CCIS

Common channel interoffice signaling

CCIR

Consultive Committee for International Radio

CCITT
(now ITU-R)

Comite Consulttatif Internationale de Telegraphique et Telephique

CCM

Continues Code Management

CCS

Common Channel Signaling, cent call second, 100 call seconds

CCSA

Common control switching arrangement

CCTV

Closed circuit television

CCSNIS

Common Channel Signaling Network Interface Specification

CCSSO

Common Channel Signaling Switching Office

CD

Committee draft, compact disk, carrier detect

CDC

Control and delay channel

CDDI

Copper distribution data interface

CDMF

Combined main distribution frame

CDN

Cable Digital Network

CDO

Community dial office, central dial office

CDPD

Cellular digital packet data

CD-ROM

Compact Disk Read Only Memory

CDMA

Code Division Multiple Access

CDT

Carrier Definition Table

CDTV

Conventional Definition Television

CDV

Cell delay variation

CDVT

Cell delay variation tolerance

C-E

Communications and electronics

CE

Consumer Electronics, collision enforcement

CEBus

Consumer Electronic Bus

CEI

Connection endpoint identifier

CEPT

Committee European Post and Telegraph

CER

Cell Error Rate

CF

Continuous Feed

CFS

Continuous Feed Session

CGC

Circuit group congestion

CGSA

Cellular geographic serving area

CHAP

Challenge Handshake Authentication Protocol

C/I

Carrier-to-interference ratio

CI

Customer installation

CIA

Classical IP over ATM

CICS

Customer information control system

CIDR

Classless inter-domain routing

CIR

Committed information rate

CLASS

Custom Local Area Signaling Services

CLAW

Common link access for workstations

CLEC

Competitive Local Exchange Carriers

CLI

Cumulative Leakage Index

CLLM

Consolidated link layer management

CLMP

Connectionless network protocol

CLNS

Connectionless network service

CLP

Cell Loss Priority

CLR

Circuit loudness rating

CM

Control Memory, Computer modem, cable modem, configuration management

CMB

CRC Message Block

CMC

Connection Management

CMCI

Cable Modem to CPE Interface

CMCS

Connection Management Controller Subsystem

CMI

Coded mark inversion

CMIP

Common Management Information Protocol

CMIS

Common Management Information Service

CMISE

Common Management Information Service Element

CMNS

Connection-mode network service

CMOS

Complimentary Metal Oxide Semiconductor

CMP

Chip-MultiProcessor

CMS

Customer Management System

CMT

Connection management

CMTS

Computer modem termination system, cable modem termination system

CNAM

Calling Name Delivery

CNCT

National technical control center (TV)

CNIS

Calling Number Identification Services

CNR, C/N

Carrier to Noise Ratio

CO

Central Office

CODEC

Coder/Decoder

COE

Central Office (exchange) Equipment

CO/HE

Central Office/Headend

COMPANDOR

Compressor-Expander

CONP

Connection-oriented network protocol

CORBA

Common Object Request Broker Architect

CoS

Class of Service

COSI

Common Operating System Interface

COSINE

Cooperation for Open Systems Interconnection Network in Europe

COT

Central office terminal

CP

Content Provider, control point

CPA

Co-polar attenuation

CPCS-PDU

Common Par Convergence Sub-layer Protocol Data Unit

CPD

Common Path Distortions

CPE

Customer Premises Equipment

CPFSK

Coherent phase frequency shift keying

CPI-C

Common Programming Interface for Communications

CPS

Characters per second

CPSK

Coherent phase shift keying

CPU

Central Processing Unit

CQPSK

Coherent quadrature (4) phase shift keying

CR/BTR

Carrier recovery/bit timing recovery (TDMA)

CRC

Cyclic Redundancy Check

CRF

Central retransmission facility (LAN)

CRE

Corrected reference equivalent

CREN

Corporation for Research and Educational Networking

CRN or C/N

Carrier-to-Noise ratio

CRTC

Canadian Radio-Television and Telecommunications Commission

CS

Convergence Sub-layer

CSA

Canadian Standards Association, carrier serving area

CSC

Common signaling channel

CSCANS

Customer Services Computer Access Network Standard

CSF

Common Simulation Framework

CSLIP

Compressed serial link internet protocol

CSO

Composite Second Order

CSMA/CD

Carrier Sense Multiple Access/Collision Detection

CSNET

Computer Science Network

CSNP

Complete sequence number PDU

CSR

Customer Service Representative

CSRE

Corrected send reference equivalent

CST

Currency System Table

CSU

Customer Service Unit, channel service unit

C/T

Carrier-to-noise temperature ratio

CT

Central Transit

CTB

Composite Triple Beat

CTD

Cell Transfer Delay

CTI

Computer Telephone Integration

CTN

Cable Termination Node

CTS

Clear to send

CTT

Child Trouble Tickets

CUI

Common User Interface

CVSD

Continuous variable slope delta modulation

CW

Control word, continuous wave, carrier wave

CWDM

Coarse Wavelength Division Multiplexing

CXR

Carrier

D/A

Digital-to-Analog Converter

DA

Destination address

DAC

Digital Access Controller, Digital to Analog Converter, dual-attached concentrator

DACS

Digital Access Cross-Connect System

DAMA

Demand assignment multiple access

DAP

Directory Access Protocol

DARPA

Defense Advanced Research Projects Agency

DAS

Dual attachment station

DASS

Demand assignment signaling and switching

DAVIC

Digital Audio-Visual Council

DB

Decibel

DBAPI

Database Application Programming Interface

dBc

Decibel relative to current

DBE

Dynamic Bandwidth Engine

DBm

Decibel related to a milli-watt

DBDS

Digital Broadband Delivery System

dBmV

Decibel related to a milli-volt

DBS

Digital Broadcasting Satellite, Digital Broadcast Service

DC, dc

Direct Current

DCA

Defense Communications Agency

DCC

Data Communications Channel, data country code

DCE

Data Communications Equipment or Data Circuit Terminating Equipment.

DCPLMTS

Digital cellular public land-mobile telecommunication system

DCR

Design Change Request

DCT

Display Channel Table, Discrete Cosine Transform

DCOM

Distributed Component Object Model

DCN

Data Communications Network

DCS

Digital Cross-Connection system

DCT

Display Channel Table

DDFS

Direct Digital Frequency Synthesis

DDL

Download Description Language

DDS

Digital Data Service, digital data system, direct-distance-dial

DE

Data Element or Discard Eligibility

DEMS

Digital Electronic Message Service

DeMux

De-Multiplexer

DENC

Digital Encryption Chip

DES

Data Encryption Standard

DF

Dedicated File

DFB

Distributed Feedback

DFT

Discrete Fourier Transform

DHCP

Dynamic Host Configuration Protocol

DHCT

Digital Home Communications Terminal

DHCTSE

Digital Home Communications Terminal Secure Element

DHEI

Digital Headend Extended Interface

DHTML

Dynamic Hypertext Markup Language

DIA

Document interchange architecture

DID

Direct Inward Dialing

DIR

Directory File

DIS

Digital Interface Service

DISA

Defense Information Systems Agency

D/L

Downlink

DLC

Digital Loop Carrier

DLCI

Data Link Connection Identifier

DLL

Data Link Layer

DLP

Decode Level Point

DLR

Design Layout Report

DLS

Down Load Server

DLSw

Data-link switching

DLU

Dependent LU

DM

Delta modulation, Disconnected Mode

DM-DFB

Direct Modulated – Distributed Feedback (Laser)

DM-FP

Direct Modulated – Fabry Perot (Laser)

DMA

Direct Memory Access, Designated Market Area

DME

Distributed Management Environment

DMM

De-Multiplexer Modulator

DMMC

De-Multiplexer Modulator Controller

DMPDU

Derived MAC Protocol Data Unit

DMS

Digital Multiplex Systems, Digital Multicast Service

DMSI

Digital Multicast Service Information

DMT

Discrete Multi-tone

DMW

Digital Milli-watt

DNA

Digital network architecture

DNCS

Digital Network Control System

DNIC

Data network identification code

DNS

Domain naming system

DNSIX

Department of Defense Intelligence Information

DO

Data Object

DOC

Dynamic Overload Control

DOCSS

Data Over Cable Security System

DOCSIS

Data-Over-Cable Service Interface Specification, CableLabs trade mark

DoD

Department of Defense

DoS

Denial of Service

DOSA

Distributed Open System Architecture

DPBX

Digital PBX

DPC

Destination Point Code

DPCM

Differential PCM

DPN

Data Packet Network

DPSK

Differential PSK

DR

Dispersion Ratio

DRS

Digital Reference Sequence

DRAM

Digital Recorded Announcement Machine, dynamic random-access memory

DQDB

Distributed Queue Dual Bus

DS

Digital Signal, Digital Service

DS-3

Digital Signal Level 3

DSAP

Destination Service Access Point

DSB

Double Sideband

DSB-SC

Double Sideband Suppressed Carrier

DSCP

Differential Services Code Point

DSE

Data Switching Exchange

DSI

Digital Speech Interpolation

DSL

Digital Subscriber Line

DSO

Digital Service, Level O

DSM

Digital Storage Media, DNCS Session Manager

DSM-CC

Digital Storage Media Command and Control

DSM-DNCS

Digital Storage Media for Digital Network Control System

DSP

Digital Signal Processing, or Processor; domain specific part

DSP-IF

Digital Signal Processor for Intermediate Frequency

DSPU

Downstream physical unit

DSR

Data set ready

DSS

Data Standards Subcommittee (SCTE), Digital Subscriber Signaling

DSS1

Digital Subscriber Signaling #1

DST

Discrete Sine Transform, Daylight Saving Time

DSU

Data Service Unit

DSX

Digital Signal cross-connect

DTC

Decoder Time Clock, Digital Transmission Channel

DTE

Data Terminal Equipment

DTL

Direct-to-line (multiplex)

DTMF

Dial Tone Multi-frequency (signaling)

DTR

Data terminal ready

DTS

Decoding Time-Stamp

DTX

Discontinuous Transmission

DUAL

Diffusing update algorithm

DUP

Data User Part

DUT

Device Under Test

DVB

Digital Video Broadcast

DVB-ASI

Digital Video Broadcasting Asynchronous Serial Interface

DVB-C

Digital Video Broadcast via Cable

DVB SI

Digital Video Broadcast Service Information

DVCR

Digital Video Cassette Recorder

DVD

Digital Versatile Disk or Digital Video Disk

DVMRP

Distance vector multicast routing protocol

DVR

Digital Video Recorder or Digital Video Recording

DVS

Digital Video Subcommittee

DVSG

Digital Video Software Group

DVT

Development or Design Verification and Test

DWDM

Dense Wavelength Division Multiplexing

DXI

Data exchange interface

EA

Entitlement Agent (Power Key), Extension Address (bit)

EAI

External Alarm Interface

EARN

European Academic Research Network

EAS

Emergency Alert System or Extended Area Service

EBCDIC

Extended Binary Coded Decimal Interchange Code

EBS

Emergency Broadcast System

EBU

Equivalent Billing Units

ECB

Electronic Code Book

ECL

Emitter Coupled Logic

ECM

Entitlement Control Message

ECMA

European Computer Manufacturers Association

ECN

Engineering Change Notice

ECO

Engineering Change Order

ECR

Engineering Change Request

EDAT

Error Data

EDE

Encryption-Decryption-Envryption

EDFA

Erbium Doped Fiber Optic Amplifier

EDH

Electronic Document Handling

EDI

Electronic Data Interchange

EDIFACT

Electronic data exchange for administration, commerce and transportation

EDP

Electronic Data Processing

EEPROM

Electrically erasable programmable ready-only memory

EF

Elementary File

EFS

Error Free Seconds, End-of-Frame Sequence

E-G

Engine-Generator

EPG

Exterior Gateway Protocol

EIA

Electronic Industries Association

EID

Entitlement Identifier

EISA

Extended Industry-Standard Architecture

ELAN

Emulated LAN

EM

Element Manager

EMI

Electromagnetic Interference

EML

Element Management Layer, Externally Modulated Laser, Electro-absorption Modulated Laser

EMM

Entitlement Management Message

EMP

Electromagnetic pulse

EMS

Element Management System

EMUL

Emulator

EN

End node

ENOB

Effective Number of Bits

ENT

Entitlement Name Table

EO

End Office (exchange)

EOC

Embedded Operations Channel

EOL

End of Line (fax)

EOM

End of Message

EOP

End of Packet

EOT

End of transmission

EPIC

Explicitly Parallel Instruction set Computer, an Intel term

EPG

Electronic Program Guide

EPP

Ethernet Packet Processor

EPROM

Erasable programmable read-only memory

ERM

Element and resource manager

ES

Exclusive Session, elementary stream, end section, errored seconds, end system

ESBI

External Status and Billing Interface

ESCON

Enterprise system connection

ESCR

Environmental Stress Crack Resistance

ESD

Electrostatic discharge

ESF

Extended Super Frame

ES-IS

End system-to-intermediate system

ESNET

Energy science network

ESP

Encapsulated Security Protocol, Enhanced Services Provider

ESS

Electronic Switching System (telephone)

ET

Exchange Termination

ETDMA

Enhanced Time Division Multiple Access

ETM

Extended Text Message

ETSI

European Telecommunication Standards Institute

ETT

Extended Text Table

ETU

Elementary Time Unit

EUID

Entitlement Unit Identification

EUnet

European internet

EUT

Entitlement Unit Table

EVT

Evaluation Verification Test

FAA

Federal Aviation Administration

FAS

Frame Alignment Signal

FAT

Forward Application Transport, frequency allocation table

FCC

Federal Communications Commission

FCS

Frame check sequence

FD

Floppy Disk

FDC

Forward Data Channel

FDDI

Fiber Distributed Data Interface

FDF

Fiber Distribution Frame

FDM/FDMA

Frequency Division Multiplex/Frequency Division Multiple Access

FDN

Fiber Deep Nodes

FDR

Frequency Domain Reflectometry

FEC

Forward Error Correction

FECN

Forward Explicit Congestion Notification

FEP

Front End Processor

FFT

Fast Fourier Transform

FID

Field Identifier

FID0

Format indicator zero

FIFO

First in, first out

FIPA

Foundation for Intelligent Physical Agents

FIPS

Federal Information Processing Standard (US)

FISU

Fill-in Signal Unit

FM

Frequency Modulation

FN

Fiber Node

FNC

Federal Networking Council

FOIRL

Fiber optic inter-repeater link

FORE

An ATM switch

FP

Filter Program, front panel, Fabry-Perot

FPGA

Field Programmable Gate Array

FPLL

Frequency and Phase Locked Loop

FPM

Forward Purchase Messages

FR

Frame Relay, Family of Requirements

FRAD

Frame relay access device

FS

Filter Set

FSC

Fiber start code

FSK

Frequency Shift Keying

FSS

Fixed Satellite Service

FST

Fast sequence transport

FT

Fiber Terminal, a trade name as in the Lucent FT-2000

FTAM

File Transfer Access and Management

FTP

File Transfer Protocol

FTTC

Fiber-to-the-Curb

FTTF

Fiber-to-the-Feeder

FTTH

Fiber-to-the-Home

GA

Grand Alliance

GB

Giga-Byte, one billion bytes

GBAM

Global Broadcast Authenticated Message

Gbps

Giga (1000 million) bits per second

GBps

Giga (1000 million) bytes per second

GDLR

Generic Design Layout Report

GDMO

Guidelines for the Definition of Managed Objects

GFC

Generic Flow Control

GGP

Gateway-to-Gateway Protocol (IP)

GigE

Gigabit Ethernet

GMT

Greenwich Mean Time

GNS

Get near server

GOP

Group Of Pictures

GOSIP

Government OSI profile

GP

General-Purpose

GPI

General Purpose Input

GPS

Global Positioning System, Global Positioning Satellite

GR

Generic Requirements

GRE

Generic routing encapsulation

GSM

Global System for Mobile Communication

GTT

Global Title Translation

GUI

Graphical User Interface

GUIDD

Graphical User Interface Design Document

GUN

Group and Unknown

H.323

The ITU-T multimedia calling over IP suite for protocol standards

HA

Hour Angle

HALO

High Altitude Long Operation

HCS

Header Check Sequence

HCT

Headend Configuration Tool, Home Communications Terminal

HCTSE

Home Terminal Security Element

HD

High Definition

HDB3

High Density Binary 3

HDLC

High-Level Data Link Control

HDPE

High-Density Polyethylene

HDR

Header

HDSL

High-speed Digital Subscriber Line

HDT

Host Digital Terminal

HDTV

High Definition Television

HEC

Header Error Control, Headend Code

HEM

Head End Modem

HEN

Head End Name

HEP

Header Extension Processing

HEX

Hexadecimal

HFC

Hybrid Fiber Coax

HG

HALO Gateway

HHP

Household-passed

HID

Hub Identifier

Hi8

High-band 8 mm Video System

HIF

Host Interface Frequency Interface

HiPHY

High Performance Physical Modulation

HIPPI

High Performance Parrelle Interface

HITS

Headend In The Sky

HMI

Human Interface

HP

Homes Passed

HPCC

High Performance Computing and Communications

HPCS

High Performance Computing and Systems

HPNA

Home Phone-line Network Alliance

HPR

High Performance Routing

HRC

Harmonically Related Carrier

HRM

High Resolution Marker

HSL

High-Signaling Link

HSRP

High Standby Router Protocol

HSSI

High Speed Serial Protocol

HTML

Hypertext Markup Language

HTTP

Hypertext Transfer Protocol

HU

High Usage

HW

Hardware

HWID

Hardware Identifier

Hz

Hertz

I/O

Input/Output

IAB

Internet Architecture Board

IANA

Internet Assigned Number Authority

IBDS

Interactive Broadband Delivery System

IBG

Installation Book Guide

IBP

Installation Book Plan

IBPD

In-Band Power Difference

IC

Integrated Circuit, Inter-exchange Carrier

ICA

Irreversible Corrective Action

ICCF

Industry Carriers Compatibility Forum

ICD

International Code Designator

ICL

Inserted Connection Loss

ICM

Inverse Channel Map

ICMP

Internet Control Message Protocol

ICN

Interconnecting CCS Network

ICT

In Circuit Test

ICW

Interrupted Continuous Wave

ID

Identifier

IDI

Initial Domain Identifier

IDL

Interface Definition Language, Inter-system Protocol and Modeling Language

IDM

Inventory and Directory Manager

IDN

Integrated Digital Network, International Data Number

IDO

Inter-Industry Data Object

IDP

Initial Domain Part

IDPR

Inter-Domain Policy Routing

IDRP

IS-IS Inter-Domain Routing Protocol

IDS

Intrusion Detection Sysytems

IE

Information Element

IEC

International Electrotechnical Commission, Inter Exchange Carrier

IEEE

Institute of Electrical and Electronics Engineers

IEEE 802.3

IEEE LAN Protocol that specifies an implementation of the physical layer and MAC sub-layer of the Data Link Layer

IESG

Internet Engineering Steering Group

IETF

Internet Engineering Task Force

IF

Intermediate Frequency

IFIP

International Federation of Information Processing

IGMP

Internet Group Message Protocol

IGP

Interior Gateway Protocol

IGMP

Internet Group Messaging (or Membership) Protocol

IGRP

Interior Gateway Routing Protocol

IGU

Integrated Gateway Unit

IIH

IS-IS Hello

IILC

Information Industry Liaison Committee

iin

Inter-ferometric Intensity Noise

IITA

Information Infrastructure Technology and Applications

ILD

Injection Laser Diode

ILEC

Incumbent Local Exchange Carriers

ILMI

Interim Local Management Interface

ILR

Issue List Report

IMACPDU

Initial MAC Protocol Data Unit

IMD

Inter-modulation Distortion

IMP

Integrated Multi-Protocol Microprocessor, Interface Message Processor

INOC

Internet Network Operations Center

INMS

Individual Network Management System

InP HEMT

Indium Phosphide High Electron Mobility Transistor

INTELSAT

International Telecommunication Satellite

I&O

Installation and Operation

IP

Internet Protocol, Intelligent Peripherals, Intellectual Properties

IPA

Internet Protocol Address

IPC

Inter Process Communication

IPG

Interactive Programming Guide

IP-PSTN or IP/PSTN

Internet Protocol Public Switched Telephone Network

IPDC

Internet Protocol Device Control, or Controller

IPI

Intelligent Peripheral Interface

IPPV

Impulse Pay Per View

IPR

Intellectual Property Rights

IPS

Iron Pipe Size

IPSEC

Internet Protocol Security

IPSO

Internet Protocol Security Option

IP/TN

Internet Protocol Address Telephone Number

Ipv4

Internet Protocol Version Four

Ipv6

Internet Protocol Version Six

IPX

Internetwork Packet Exchange

I/Q

In-Phase Quadrature

IR

Infra Red Radiated signal

IRC

Incrementally Related Carrier

IRD

Integrated Receiver-Decoder

IRN

Intermediate Routing Node

IRT

Integrated Receiver Transcoder

IS

Intermediate System

ISA

Interactive Services Association, Industry-Standard Architecture

ISAT

Input Session Association Table

ISDN

Integrated Services Digital Network

ISDNUP

Integrated Services Digital Network User Part of the SS7 protocol

ISI

Industry Support Interface, Inter-symbol Interference

IS-IS

Intermediate System-to-Intermediate System

ISP

Internet Service Provider

ISO

International Standards Organization

ISOC

Internet Society

ISODE

ISO Development Environment

ISR

Intermediate Session Routing

ISSI

Inter-Switching System Interface

ISV

Independent Software Vendor

IT

Information Technology

ITT

Inter-tandem Trunk

ITU

International Telecommunication Union

ITU-T

International Telecommunications Union – Transmission, or International Telecommunications Union - Telecommunications

IVSN

Interactive Video Services Network

IXC

Inter-Exchange Carrier

JANET

Joint Academic Network

JAVA

Interpreted Programming Language licensed by Sun Microsystems

JEC

Joint Engineering Council of EIA/CE and NCTA

JEDEC

Joint Electron Device Engineering Council

JPEG

Joint Photographic Expert Group

JMX

Jumbo Multiplex

JUNET

Japan Unix Network

K

Karn’s Algorithm

KB

Kilo Byte

KBps

Kilo Bytes per second

Kbps

Kilo-bits per second

KHz

Kilo-Hertz

KLS

Key-list Server

KSU

Key Service Unit

L1

Level 1

LANE

LAN Emulation

LAIS

Line Alarm Indicator Signal

LAN

Local Area Network

LAPB

Link Access Control – B, Link Access Procedure, Balanced

LAPD

Link Access Control – D, Link Access on D Channel

LAT

Local Area Transport

LATA

Local Access Transport Area

LBC

Local Bus Controller

LCC

Life Cycle Cost

LCI

Logical Channel Identifier

LCN

Logical Channel Number

LCR

Local Clock Reference

LCT

Logical Channel Table

LD

Long Distance

LDAP

Lightweight Directory Access Protocol

LEC

Local Exchange Carrier, LAN Emulator Client

LECS

LAN Emulator Configuration Server

LED

Light Emitting Diode

LERG

Local Exchange Routing Guide

LES

LAN Emulator Server

LFE

Low Frequency Effect, < 120 Hz

LID

LAN Interconnect Device

LIDB

Line Information Database

LIT

Link Integrity Test

LLC

Logical Link Control

LLNL

Lawrence Livermore National Laboratory

LMDS

Local Multipoint Distribution Service

LMI

Local Management Interface

LNA

Low Noise Amplifier

LNM

LAN Network Manager

LNP

Local Number Portability

LO

Local Oscillator

LOC

Line Of Code

LOS

Loss of Optical Signal

LP

Low Pass

LPD

Line Printer Daemon

LPF

Low Pass Filter

LSA

Link-State Advertisement

LSb

Least Significant Bit

LSB

Least Significant Byte

LSP

Link-State Packet

LSPP

Local Service Provider Portability

LSSGR

LATA Switching System Generic Requirement, FR-TSY-000064

LT

Line Termination, Local Tandem, Local Time

LU

Logic unit

LUG

Line Up Group

LWPF

Low Water Peak Fiber

MA

Memory Administration, Milli-Ampere(s)

MAC

Medium Access Control

MAP

Media Accelerated Processor, GM’s Manufacturing Automation Protocol

MAN

Metropolitan Area Network

MATV

Master Antenna Television System

MAU

Medium Attachment Unit, Media Attachment Unit

Mb

Megabit, one million bits

MB

Megabyte, one million bytes

MBE

Molecular Beam Epitaxy

Mbps

Mega bits per second

MCA

Micro Channel Architecture

MCC

MAC Common Convergence

MCI

Multi-port Communication Interface

MCNS

Multimedia Cable Network System

MCPT

Multiple Carriers per Transponder

MCR

Minimum Call Rate

MCU

Microprocessor Control Unit

MCT

MAC Controller Task, Multiplex Control Terminal

MD

Mini-disc digital video format, Mediation Device

MD5

Message Digit 5

MDF

Main Distribution Frame

MECOD

Multiple Exchange Carriers Ordering and Design

MESFET

Metal-Semiconductor Field Effect Transistor

MF

Master File

MFA

Management Functional Areas

MFLOP

Million Floating Point Operations per Second

MFN

Mini-Fiber Node

MGCP

Media Gateway Control Protocol

MGT

Master Guide Table

MIC

Media Interface Connector

MHz

Mega-Hertz

MIB

Management Information Bases

MILNET

Military Network

MIPS

Million of Instructions per Second

MISO

Master In – Slave Out

MJD

Modified Julian Date

MLA

Minimum Look Angle

MMDS

Multichannel Multipoint Distribution Service, or Microwave Multipoint Distribution System

MMI

Man Machine Interface

MMT

Modulation Mode Table, Modulator Management Task

MMW

Millimeter Wavelength

MNT

Map Name Table

MODEM

Modulator/Demodulator

MOP

Maintenance Operation Protocol, method of procedure

MOSI

Master Out – Slave In

MOSPF

Multi-cast OSPF

MP3

MPEG 2 Layer 3 (sound)

MPAA

Motion Picture Association of America

MPEG

Moving Pictures Expert Group, Motion Picture Expert Group

MP@HL

Main Profile at High Level

MP@ML

Main Profile at Main Level

MPLS

Multi Protocol Label Switching

MPOA

Multi Protocol Over ATM

MQI

Message Queuing Interface

MRB

Message Recovery Block

MRD

Marketing Requirement Document

MRT

Modular Receiver Transcoder

MRTG

Multiple Router Traffic Grapher

MSAU

Multi-Station Access UNit

MSb

Most Significant Bit

MSB

Most Significant Byte

MSC

MAC Service Control, Mobile Services Switching Center

MSK

Multi-Session Key

MSO

Multiple System Operator

MSYNC

Master Synchronization – Clock signal

MTA

Multimedia Terminal Adapter

MTBF

Mean Time Between Failures

MTP

Message Transfer Part of the SS7 protocol

MTS

MPEG Transport Stream

MTT

Master Trouble Tickets

MTTF

Mean-Time-to-Failure

MTTR

Mean-Time-to-Repair

MTU

Maximum Transmit Unit

MUX

Multiplexer

MW

Milli-Watt

N

Nagle’s Algorithm

NA

Numerical Aperture, Network Architecture

N/A

Not Applicable, Not Available

NABTS

North American Basic Teletext Specification

NAD

Network Access Device

NAK

Not Acknowledged, Negative Acknowledgement

NANP

North American Numbering Plan

NAP

Network Access Point

NAPLPS

North American Presentation Level Protocol Syntex

NAT

Network Address Translation

NAU

Network Addressable Unit

NAUN

Nearest Active Upstream Neighbor

NAB

Name Binding Protocol

NBMA

Non-Broadcast Multi-Access

NBS

National Bureau of Standards (NIST today)

NC

Network Channel, Numerical Control

NCAS

Non-Call Associated Signaling

NCI

Network Channel Interface

NCLD

National Center for the Law and Deaf

NCP

Network Control Program

NCTA

National Cable Television Association

NDA

Non-Disclosure Agreement

NDC

Network Data Collection

NDIS

Network Driver Interface Specification

NE

Network Element

NEC

National Electrical Code

NEI

Network Element Interface

NEL

Network Element Layer

NESC

National Electrical Safety Code

NET

Network Entity Title

NF

Noise Figure

NFS

Network File System

NI

Network Inventory

NIC

Network Interface Card, National ISDN Card, Network Information Center

NID

Network Interface Device

NIM

Network Interface Module

NISDN

Narrow-band ISDN

NIT

Network Information Table

NIU

Network Interface Unit

NHRP

Next Hop Resolution Protocol

NLM

NetWare Load-able Module

NLSP

NetWare Link Services Protocol

NMAPS

Network Management and Provisioning Station

NML

Network Management Layer

NMS

Network Management System

NMVT

Network Management Vector Transport

NNI

Network to Network Interface, Network to Node Interface

NNTP

Net News Transfer Protocol

NOC

Network Operations Center

NOF

Network Operations Forum

NOI

Notice of Inquiry

NOS

Network Operating System

NP

Network Provider

NPA

Numbering Plan Area

NPAC

Number Portability Administration Center

NPR

Noise Power Ratio

NRM

Normal response mode

nrtVBR

Non-real time Variable Bit Rates

NRZ

Non-return to zero

NRZI

Non-return to zero inverted

NSAP

Network Service Access Point

NSFNET

National Science Foundation Network

NSI

Network Side Interface

NT

Network Termination

NTM

Network Traffic Management, Network Traffic Manager

NTMOS

Network Traffic Management Operations System

NTP

Network Time Protocol

NTRI

NCP/Token Ring Interconnection

NTSC

National Television System Committee (US)

NVM

Non-Volatile Memory

NVOD

Near Video On Demand

NVSC

Non-Volatile Storage Cell

NXX

End-Office Code

NYSERNet

Network in New York State

OC-3

Optical Carrier Level 3

OADM

Optical Add/Drop Multiplexer

OAM

Operations and Maintenance, Operation, Administration and Maintenance

OBF

Ordering and Billing Forum

OBM

Out-of-Band Modulator

OC

Optical Carrier

OC48

Optical Carrier # 48

ODA

Open Document Architecture, Office Document Architecture

ODI

Open Data-Link Interface

OEM

Original Equipment Manufacturer

OF

Over Flow

OFA

Optical Fiber Amplifier

OIM

OSI Internet Management

ONC

Open Network Computing

OOB

Out-of-Band

OLNS

Originating Line Number Screening

OA&M

Operation, Administration and Maintenance

OMG

Object Management Group

OMI

Optical Modulation Index

OMS

Object Management Server

ONA

Open Network Architecture

ONU

Optical Network Unit

OPC

Originating Point Code

OpenCable

Open cable for set-top boxes, a CableLabs trade mark

OQPSK

Offset Quadrature Phase Shift Key

ORB

Object Request Broker

ORX

Optical Receiver

OS

Operating Systems

OSAT

Output Session Association Table

OSF

Operations System Function

OSI

Open Systems Interconnection

OSP

Outside Plant, in the Hybrid Fiber Coax description

OSPF

Open Shortest Path First

OSS

Operation Support Systems

OSSGR

Operator Services Systems Generic Requirements

OTF

On The Fly settings

OTGR

Operations Technology Generic Requirements

OTX

Optical Transmitter

OUI

Organization Unique Identifier

P-1394

A fire wire specification of IEEE, also see 1394

PA

Physical Address

PAD

Packet assembler or Disassembler

PAE

Power-Added-Efficiency

PAL

Phase Alternation by Line (European 50 Hz analog TV standard)

PAM

Pulse Amplitude Modulation

PAP

Password Authentication Protocol

PARC

Palo Alto Research Center

PAT

Program Association Table

PBX

Private Branch Exchange

PCD

Product Control Drawing, Product Control Document

PCI

Personal Computer Interconnect, Protocol Control Information

PCI Bus

Peripheral Control Interconnect Bus

PCM

Pulse Code Modulation

PC-MCIA

Personal Computer - Memory Card International Association

PCN

Personal Communications Network

PCR

Program Clock Reference, Peak Cell Rate

PCS

Personal Communications Services

PDA

Personal Digital Assistant

PDH

Plesiochronous Digital Hierarchy

PDF

Portable Document Format

PDN

Public Data Network, Power Domain Node

PDS

Packet Delivery System

PDU

Protocol Data Unit

PE

Pre-Encryption

PEN

Private Enterprise Number

PES

Packetized Elementary Stream

PETE

Power Error and Timing Error Message

P/F

Poll/Final bit

PGP

Pretty Good Privacy

PH

Primary Hub, Primary Head End

PHD

Power Hybrid Doubler

PHY

Physical Layers

PID

Packet Identifier, Process Identifier

PIM

Protocol Independent Multi-cast

PIM DM

PIM Dense Mode

PIM SM

PIM Sparse Mode

PIN

Personal Identification Number

PING

Packet Internet Groper

PIX

Proprietary Application Identifier Extension

PKCS

Public Key Cryptography Standards

PKI

Public Key Infrastructure

PKYCS

Power Key Control Suite

PLCP

Physical Layer Convergence Protocol or Procedure

PLD

Programmable Logic Device

PLL

Phase Locked Loop

PLP

Packet Level Protocol

PLU

Primary Logic Unit

PM

Phase Modulation, Physical Medium

PMD

Physical Media Dependent

PMT

Program Map Table

PNNI

Private Network-Network Interface

POF

Plastic Optical Fiber

PON

Passive Optical Network

POP

Point of Presence

POSIX

Portable Operating System Interface Unix

POTS

Plain Old Telephone Service

PPC

Power Personal Computer

PPK

Private-Public Key

PPP

Point-to-Point Protocol

PPV

Pay Per View

PRBS

Pseudo-Random Bit Stream, Pseudo-Random Binary Sequence

PRI

Primary Rate Interface

PROM

Programmable Read-Only Memory

PS

Power Supply, Program Stream

PSDN

Packet-Switch Data Network

PSE

Packet Switch Exchange

PSI

Program Specific Information

PSIP

Program and Systems Information Protocol

PSK

Phase Shift Keying

PSN

Public Switched Network, Packet Switched Data Network

PSTN

Public Switched Telephone Network

PSTN-IP

Public Switched Telephone Network – Internet Protocol

PT

Problem Tracking

PTC

Program Transmission Channel

PTI

Payload Type Identifier

PTR

Problem Tracking Report

PTS

Protocol Type Selection, Presentation Time Stamp

PTT

Post, Telephone, and Telegraph

PTV

Power Television Manager

PU

Presentation Unit, Physical Unit

PUP

PARC Universal Protocol

PUSI

Payload Unit Start Indicator

PVC

Permanent Virtual Circuit/Connection, Polyvinyl Chloride, Personal Video Channel

PVCS

Project Version Control System

PVP

Permanent Virtual Path

PVR

Personal Video Recorder

PWB

Printed Wiring Board

QAM

Quadrature Amplitude Modulation

QAMEM

QAM Element Manager

QLLC

Qualified Logical Link Control

QOS

Quality of Service

QPRS

Quadrature Partial Response Signaling

QPSK

Quadrature Phase Shift Key

RA

Resident Application

RAC

Residential Account Coordinators

RACE

Research and Advanced Committee in Europe

RARP

Reverse Address Resolution Protocol

RBOC