NAM - Number Assignment Module

NAU - Network Access Unit

NAUN - Nearest Available Upstream Neighbor

NBMA -Non-Broadcast Multiple Access

NC - Normally Closed

NCC - Network Control Center

NCS - National Computer Systems (subcontractor to NECA)

NDIS - Network Driver Interface Specification

NE - Network Element

NEBS - Network Equipment Building Spec

NECA - National Exchange Carrier Association (contractor responsible for forms processing)

NEMA - National Electrical Manufacturers Association

NETBIOS - Network Basic Input/Output System

NEXT - Near End Crosstalk (adverse phenomenon associated with high frequencies over twisted pair wiring measured in decibels)

NHRP - Next Hop Resolution Protocol

NHS - Next Hop Server

NIC - Network Interface Card

NICNAME - Network Information Center Name Service

NIU - Network Interface Unit

NIWF - Network Interworking Function

NLPID - Network Layer Protocol ID

NM - Network Management

NMCC - Network Management Control Center

NME - Network Management Entity

NML - Network Management Layer

NMS - Network Management Station

NMVT - Network Management Vector Transport

NNI - Network-to-Network Interface

NO - Normally Open

NRZ - Non-Return to Zero

NRZI - Non-Return to Zero Inverted

NSAP - Network Layer Service Access Point

NSF - National Science Foundation Network

NTSC - National Television Standards Committee

OAM - Operations, Administration, and Maintenance

OCA - Over Current Alarm

OCC - Other Common Carriers

OCD - Out-of-Cell Delineation (UNI 3.0 Section 2.1.2.2.2)

OC-n - Optical Carrier-n

ODI - Open Data Link Interface

OEM - Original Equipment Manufacturer

ONA - Open Network Architecture

OOF - Out of Frame

OOS - Out of Service

OS - Operating System

OSI - Open Systems Interconnect

OSP - Outside Plant

OSPF - Open Shortest Path First

OUI - Organizationally Unique Identifier (RFC 1483)