Fiber Optics Network & Monitoring Glossary (Acronyms)

Reference list of common acronyms and terms you may encounter in Fiber Optics, Remote Fiber Test Systems (RFTS) and PON applications

1:N - Splitter ratio

4G - Fourth Generation mobile network infrastructure

5G - Fifth Generation mobile network infrastructure

APC - Angled Physical Contact (type of connector end face, e.g. SC-APC)

API - Application Programming Interface

A-PON - ATM Passive Optical Network

ARPU - Average Revenue Per User

ATM - Asynchronous Transfer Mode (data transmission technology)

B-PON - Broadband Passive Optical Network (ITU-T)

BiDi - Bidirectional optical interface using a single strand of fiber, using different wavelengths for each transmission direction.

CAPEX - Capital Expenditures

CEx - Coexistence Element

CO - Central Office

Colored Optics - Optical interfaces with specific (or tunable) wavelength used for WDM and coexistence applications

CSP - Communication Service Provider

CWDM - Coarse Wavelength Division Multiplexing

DAA - Distributed Access Architecture

dB - Decibels (relative measure of power gain or loss)

dBm - Decibel-milliwatt (measure of power level, referenced to 1 mW)

DUT - Device Under Test

DW - Downstream Wavelength

DWDM - Dense Wavelength Division Multiplexing

E2E - End To End

E-PON - Ethernet Passive Optical Network (IEEE)

F1/F2 - Multi-fiber cables connecting 1st and 2nd stage splitters

FC - Ferrule Connector (type of 2.5mm fiber optic connector) 

FCC - Federal Communications Commission (USA)

FDH - Fiber Distribution Hub

FL - Fault Locator

FTTB - Fiber To The Building

FTTC - Fiber To The Curb or Cabinet

FTTH - Fiber To The Home

FTTP - Fiber To The Premise

FTTx - Generic for FTTB, FTTH, FTTP, etc.

FUT - Fiber Under Test

FWDM - Filtered Wave-Division Multiplexer 

G-PON - Gigabit-capable Passive Optical Network (ITU-T)

GE - Gigabit/s Ethernet

GIS - Geographic Information (management) System

Grey Optics - Optical interfaces with fixed wavelengths at commonly used 850nm, 1300nm 1310nm, 1550nm.

HFC - Hybrid Fiber-Coaxial access network architecture

IEC - International Electrotechnical Commission (international standardization body)

IEEE - Institute of Electrical and Electronic Engineers (international standardization body)

ISP - Internet Service Provider

ITU-T - International Telecommunication Union - Telecom (international standardization body)

KML - Keyhole Markup Language (File format used to display geographic data in Earth/Map browsers)

KPI - Key Performance Indicators

LC - Lucent Connector (type of 1.25mm fiber optic connector) 

LTS - Loss Test Set (test equipment)

MDU - Multi-Dwelling Unit (e.g., apartment building)

MPO - Multi-fiber Push-On connector (also known as MTP)

MSO - Multiple System Operator (often refer to cable TV providers offering multiple services, such Internet and phone)

MTP - Multi-fiber Push-On connector (also known as MPO)

MTTR - Mean Time To Repair

MTU - Multi-Tennant Unit (e.g., office building)

mW - Milliwatt (unit of power)

NE - Network Element

NG-PON2 - Next Generation Passive Optical Network (ITU-T) 

nm - Nanometer (wavelength)

NMS - Network Management System

NNI - Network-to-Network Interface

NOC - Network Operation Center

NTE - Network Termination Equipment

OCC - Optical Channel Checker (multi-wavelength meter, test equipment)

OCM - Optical Channel Monitor (multi-wavelength meter, test equipment)

ODN - Optical Distribution Network (includes fibers and splitters between OLT and ONU/ONT)

OLT - Optical Line Terminal

OLTS - Optical Loss Test Set (test equipment)

ONT - Optical Network Terminal (ITU-T)

ONU - Optical Network Unit (IEEE)

OOS - Out Of Service

OPEX - Operational Expenditures

OPM - Optical Power Meter (test equipment)

OSA - Optical Spectrum Analyzer (test equipment)

OSP - Outside Plant

OSS - Operations Support System

OTDR - Optical Time-Domain Reflectometer (test equipment)

P2P - Point To Point (link or network architecture)

PC - Physical Contact (type of connector end face, e.g. SC-PC)

PLOAM - Physical Layer Operations, Administration and Maintenace messages

PNM - Proactive Network Monitoring

POL - Passive Optical Local area network

PON - Passive Optical Networks (point-to-multipoint architecture)

QoE - Quality of Experience

QoS - Quality of Service

R-PHY - Remote PHY architecture

RDOF - Rural Digital Opportunity Fund (USA initiative to promote the construction and operation of rural broadband networks)

RFoG - Radio Frequency Over Glass

RFTS - Remote Fiber Test (and monitoring) System

RPO - Recovery Point Objectives

RTO - Recovery Time Objectives

RTU - Remote Test Unit (centralized test head or probe consisting of OTDR and optical switches)

SC - Subscriber Connector (type of 2.5mm fiber optic connector) 

SLA - Service Level Agreement

SMNP - Simple Network Management Protocol

SOR - Standard OTDR Record (trace file) 

SUT - System Under Test

TDMA - Time Division Multiplex Access

Telco - Telephone Company (now offering multiple services, such Internet and video)

THz - Terahertz (frequency)

TLS - Tunable Laser Source

UNI - Uset-to-Network Interface

UW - Upstream Wavelength

WDM - Wavelength Division Multiplexing

WFM - Work From Home (telecommuting)

WMS - Web Map Service

XG-PON - 10G Passive Optical Network

XGS-PON - 10G Symmetrical Passive Optical Network

XG(S)-PON - Generic for XG and XGS PON

X-haul - Generic for Fronthaul, Midhaul and Backhaul cellular communication links

xWDM - Generic for DWDM and CWDM

λ - Lambda. Represents a laser wavelength (nm or THz)

Related Test & Measurement Tools

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