A

AAA Authentication, Authorization, Accounting

AAL ATM Adaptation Layer

AARP Apple Talk Address Resolution

ABC Automatic Broadcast Controller – HP 

ABM Asynchronous Balanced Mode

ABR Available Bit Rate

ACD Automatic Call Distribution

ACELP Agelbraic Code-Excited Linear Predictive

ACF Advanced Communication Function – IBM 

ACK Acknowledge

ACL Access Control List

ACR Allowed Cell Rate - ATM

ADCCP Advanced Data Communications Control Protocol

ADM Add Drop Multiplexer

ADMD Administration Management Domain - X.400

ADPCM Voice Compression Method : Adaptive Differential Pulse Code Modulation

ADR Advanced Digital Recording

ADSL Asymmetrical Digital Subscriber Line

AGP Accelerated Graphics Port

AH Authentication Header

AHIP Authentication Header IP

AIFF Audio Interchange File Format

AIN Advanced Intelligent Network - Telephony

AIS Alarm Indication Signal - ATM

AIT-2 Advanced Intelligent Tape - Sony®

AIX Advanced Interactive eXecutive - IBM ®

AM Amplitude Modulation

AMD Advanced Micro Devices ®

AME Advanced Metal Evaporated

AMI Alternate Mark Inversion - ATM

AMI American Megatrends Inc. ®

AMPS Advanced Mobile Phone Service

ANI Automatic Number Identification

ANSI American National Standard Institute

AOL America On Line 

APC American Power Conversion 

API Application Programming Interface

APIPA Automatic Private IP Addressing

APM Advanced Power Management

APPC Advanced Program-to-Program Communications – IBM 

APL A Programming Language

APPN Advanced Peer-to-Peer Networking – IBM 

APS Advanced Photo System

APS Automatic Protection Switching - Sonet

ARJ Archive Robert Jung

ARM Asynchronous Response Mode

ARP Address Resolution Protocol

ARPANET Advanced Research Project Agency Network

ARQ Admission Repeat Request

ASCII American Standard Code for Information Interchange

ASF Advanced Streaming Format

ASIC Application Specific Integrated Circuits

ASMP ASymmetric MultiProcessing

ASN Abstract Syntax Notation

ASP Active Server Page - Microsoft ®

ASP Application Service Provider

ASPI Advanced SCSI Programming Interface

ASR Automated System Recovery - Microsoft ®

ASYNCHRONE
ATA Advanced Technology Attachment

ATAPI Advanced Technology Attachment Packet Interface

ATD Asynchronous Time Division

ATM Asynchronous Transfer Mode

ATM Adobe  Type Manager

A to A Application to Application

AUI Attachment Unit Interface

AURP Apple-Talk Update based Routing Protocol

AVI Audio Video Interleaved – Microsoft 

AVM ATM Voice Multiplexer

AVVID Architecture for Voice, Video, and Integrated Data - Cisco ®

BAP Bandwidth Allocation Protocol

BALUN Balanced Unbalanced

BASIC Beginners All Purpose Symbolic Instruction Code

BAT Batch file

BBN Bolt Beranek And Newman 

BBS Bulletin Board System

B channel Bearer Channel - ISDN

BCD Binary Coded Decimal

BCP Bridging Control Protocol

BDCS Broadband Digital Cross-Connect System - SONET

BEACONING

BECN Backward Explicit Congestion Notification

BER Basic Encoding Rule

BERT Bit Error Rate Test

BGP Border Gateway Protocol

BICI Broadband Inter - Carrier Interface

BIND Berkeley Internet Name Domain

BIP Bit Interleaved Parity - ATM

B-ISDN Broadband Integrated Services Digital Network

BLSR Bi-directional Line Switch Ring – SONET

BIOD Block Input / Output Daemon

BIOS Basic Input / Output System

BIT Binary Digit

BMP BitMap - File System

BNC Bayonet Neil Concelman Connector

BNI Broadband Network Interface

BNM Broadband Network Module

BOOTP Bootstrap Protocol

“BOTS” Knowledge Robots

BPDU Bridge Spanning Tree Protocol - Bridge Protocol Data Unit

BPS Bit Per Second

BRI Basic Rate Interface - ISDN

BRIDGE

BSA Business Software Alliance

BSC Binary Synchronous Communication

BT British Telecom

BT Burst Tolerance - ATM

B2B Business-to-Business

B2C Business-to-Consumer

BYTE 8 bits

CA Certificate Authority

CABLING

CAC Connection Admission Control - ATM

CAD Computer-Aided Design

CAL Client Access License

CAM Controlled Attachment Module

CAR Committed Access Rate - Cisco ®

CARP Cache Array Routing Protocol

CAS Channel Associated Signaling

CATV Community Antenna Television

CAU Controlled Access Unit

CBAC Context Based Access Control - Cisco 

CBR Constant Bit Rate - ATM

CBWFQ Class Based Weighted Fair Queuing – Cisco 

CCD Couple Charge Device

CCIE Cisco Certified Internetwork Expert – Cisco 

CCITT Consultative Committee on International Telegraphy and Telephones

CCP Compression Control Protocol

CCS Cascading Style Sheet

CCS Common Channel Signaling

CD Compact Disc

CD Carrier Detect - Modem

CDDI Copper Distributed Data Interface

CDF Channel Definition Format – Web / XML

CDFS Compact Disc File System

CD-I Compact Disc - Interactive

CDMA Cellular Division Multiple Access

CD-R Compact Disc – Recordable

CDRM Cross Domain Resource Manager

CD-ROM Compact Disc-Read-Only Memory

CD-RW Compact Disc - Read Write

CDV Cell Delay Variation

CDVT Cell Delay Variation Tolerance - ATM

CDWFQ Called Distributed Weighted Fair Queuing - Cisco ®

CD-WO Compact Disc - Write Once

CD-WORM Compact Disc - Write Once Read Many

CD-XA Compact Disc eXtended Architecture

CEI Connection Endpoint Identifier

CELP Code Excited Linear Prediction

CEP Certificate Enrollment Protocol - Cisco ®

CER Cell Error Ratio

CES Circuit Emulation Service - ATM

CGA Color Graphics Array – IBM 

CGI Common Gateway Interface

CGM Computer Graphics Metafile - File System

CH C-Shell

CHAP Challenge Handshake Authentication Protocol

CGI Common Gateway Interface

CICS Customer Information Control System

CID Caller Identification

CID Channel ID - ATM

CIDR Classless Inter Domain Routing

CIM Common Information Model

CIR Committed Information Rate - comment

CISCO San Francisco – 1984

CIX Commercial Internet eXchange

CLI Caller Line Identification

CLI Command Line Interface / Interpreter

CLID Calling Line Identification

CLNP Connectionless Network Protocol

CLNS Connectionless Network Service - ATM

CLTP Connectionless Transport Protocol - OSI

CMIP Common Management Interface Protocol

CMOS Complementary Metal Oxide Semiconductor

CMOT CMIP Over TCP-IP

CMS Conversational Monitor System – IBM 

CMTS Cable Modem Termination System

CNA Cisco ® Networking Academies

CNID Calling Party Name Identification – IP Telephony

COBOL Common Business Oriented Language

CODEC Coder Decoder

COM Component Object Model

COM Commercial Business

CORBA Common Object Request Broker

COREL COwpland REsearch Labs ® - Canadian software company / 1985

COS Class Of Service

COSE Common Opened System Environment - HP ®/ IBM ® / SCO ®

CP Control Point – IBM 

CPI Character Per Inch

CPU Central Processing Unit

CRC Cyclic Redundancy Check

CRL Certificate Revocation List - Cisco ®

CRT Cathode Ray Tube

CS Carrier Selection

CS-ACELP Conjugate Structure Algebraic CELP

CSI Called Subscriber Identification

CS-SLIP Compressed Serial Link Internet Protocol

CSMA-CD Carrier Sense Multiple Access with Collision Detection

CSS Cascading Style Sheet - Internet

CSTA Computer Supported Telecommunications Applications

CSU Channel Service Unit

CTD Cell Transfer Delay - ATM

CTI Computer Telephony Integration

CTS Clear To Send

CUG Closed User Group

CUT Control Unit Terminal – IBM 

CXML Commerce Extensible Markup Language

D

DA Destination Address

DAC Digital to Analog Converter

DAC Dual-Attached Concentrator - FDDI

DAEMON Disk And Execution MONitor - Unix

DAP Directory Access Protocol – X.500

DARD Dynamic Resource Allocation and Distribution

DAS Dual Attachment Station - FFDI attachment

DASD Direct Access Storage Device

DAT Digital Audio Tape

dB Decibel

DB2 Data Base - IBM ®

DBF DBase File

DBML DataBase Markup Language

DBMS Data Base Management System

DCA Document Content Architecture - IBM ® / SNA - File System

DCA Data Communication Architecture

DCAP Data Link Switching Client Access Protocol

DCC Data Country Code - ATM

D-Channel Data Channel - ISDN

DCE Data Communication Equipment

DCF Data Composition Facilities

DCOM Distributed Component Object Model

DDE Dynamic Data Exchange

DDM Distributed Data Management - IBM ®

DDP Datagram Delivery Protocol - AppleTalk ™

DDR Dial-on-Demand Routing - ISDN

DDR Double Data Rate - RAM - AMD ®

DDRSDRAM

DDS Digital Linear Tape – Hewlett-Packard

DE Discard Eligibility

DEC Digital Equipment Corporation - Compaq  since 1999

DECT Digital Enhanced Cordless Telecommunications

DEK Data Encryption Key

DEN Directory Enabled Network

DES Data Encryption Standard

DFS Distributed Files Systems

DFT Distributed Functional Terminal – IBM 

DHCP Dynamic Host Configuration Protocol

DHTML Dynamic Hypertext Markup Language

DID Direct Inward Dial

DIMM Dual In-line Memory Module

DIN Deutsche Industrie Norm connector

DIP Dial-Up Internet Protocol - Linux

DIP Switch Dual In-line Pin Switch - RAM

DIT Directory Information Tree - X.500

DIX DEC, Intel, Xerox

DKU

DLC Data Link Control

DLCI Data Link Connection Identifier

DLL Dynamic Link Library

DLT Digital Linear Tape - Quantum®

DLU Dependent Logical Unit - SNA / SSCP

DMA Direct Memory Access

DMD Digital Micro mirror Device

DMTF Distributed Management Task Force

DMZ Demilitarized Zone

DN Distinguished Name - X.500

DNIS Dial Number Id Service

DNS Domain Name Server

DOD – ARPA Department of Defense's Advanced Research Project Agency

DOD Direct Outward Dial

DOS Disk Operating System

DPI Dot Per Inch

DPOF Digital Print Order Format

DPMI DOS Protected Mode Interface

DQDB Distributed Queue Dual Bus - IEEE 802.6

DRAM Dynamic Random Access Memory

DRDA Distributed Relational Database Architecture - IBM ®

DRDRAM Direct Rambus Dynamic Random Access Memory

DSA Directory System Agent - X.500

DSAP Destination Service Access Point

DSIMM Dual Single Inline Memory Module

DSL Digital Subscriber Line

DSO Dynamic Shared Object - Unix

DSOM Distributed System Object Model - IBM ®

DSN Data Source Name

DSP Digital Signal Processor

DSPU Down Stream Physical Unit

DSR Data Set Ready - Modem

DSRS Data Signal Rate Selector

DSS Directory and Security Services

DSU Digital Service Unit

DTE Data Terminal Equipment

DTMF Dual Tone Multi Frequency

DTR Data Terminal Ready - Modem

DUV Directory User Agent - X.500

DVB Digital Video Broadcasting

DVD Digital Video Disc

DVDR Digital Video Disc Recordable

DVI Digital Video Interface

DVMRP Distance Vector Multicast Routing Protocol

DWDM Dense Wavelength Division Multiplexing

DXI Data Exchange Interface - ATM - RFC 1483

EAN

EAP Extensible Authentication Protocol

EBCDIC Extended Binary Coded Decimal Interchange Code

E-Bi E-Business Intelligence

ECF Enhanced Connectivity Facilities – IBM 

ECP Enhanced Capability Port

EDIFACT Electronic Data Interchange for Administration Commerce and Transport

EDGE Enhanced Data Rates for Global Evolution

EDI Electronic Data Interchange

EDO Extended Data Output - RAM

EECM End to End Call Manager - Cisco ®

EEPROM Electrically Erasable Programmable Read Only Memory

E&M recEive and transMit /or Ear & Mouth

EFCI Explicit Forward Congestion Indication

EFR Enhanced Full Rate

EFS Encrypting File System

EGA Enhanced Graphics Array – IBM 

EGP Exterior Gateway Protocol

EHLLAPI Enhanced High-Level Language Application Interface

EIA Electronic Industries Association

EIDE Enhanced Integrated Device Electronics

EIGRP Enhanced Interior Gateway Protocol

EISA Extended Industry Standard Architecture

ELAN Education Language

ELAN Emulated LAN - ATM

E-MAIL Electronic Mail

EN End Node - APPN PU2.1 - IBM ®

EOF End Of File

EOM End Of Message - ATM

EPD Early Packet Discard - ATM

EPIC Explicitly Parallel Instruction Computing – Intel 

EPP Enhanced Parallel Port

EPROM Erasable Programmable Read-Only Memory

ER Explicit Rate - ATM

ESCON Enterprise System Connection - IBM ®

ESDI Enhanced Small Device Interface

ES-IS End System-to-Intermediate System - OSI

ESMTP Extended Simple Mail Transfer Protocol – RFC 1869

ETSI European Telecommunications Standards Institute

ETHERNET

FALSE MODEM

FAQ Frequently Asked Questions

FAS Frame Alignment Sequence - Telephony

FAT File Allocation Table

FCB File Control Block

FCC Federal Communications Commission

FC-PGA Flip Chip - Pin Grid Array – Intel 

FCS Frame Check Sequence

FD Flat Display

FDDI Fiber Distributed Data Interface

FDM Frequency Division Multiplexing

FEC Fast Ethernet Channel - HP

FECN Forward Explicit Congestion Notification

FF Form Feed

FIFO First In First Out

FLOPS Floating-point Operations Per Second

FIREWIRE IEEE 1394

FLT Full Line Terminal - Sonet

FM Frequency Modulation

FORTRAN FORmula TRANslation

FRAD Frame Relay Assembler Dissembler

FRAME RELAY

FRF.11 Frame Relay Forum – Voice Over Frame Relay

FRF.12

FSAA Full-Screen Anti Alisasing

FSB Front Side Bus – Intel 

FTP File Transfer Protocol

FULL DUPLEX

FXO Foreign Exchange Office

FXS Foreign Exchange Station

G.711

G.733 / T1

GB Giga Bytes

GDI Graphical Device Interface

GDDM Graphical Data Display Manager - IBM ®

GDT Global Descriptor Table

GIF Graphics Interchange Format

.GOV Government

GPC Group Policy Container - Microsoft ®

GPO Group Policy Object - Microsoft ®

GPRS General Packet Radio Service

GSM Global System for Mobile

GUI Graphical User Interface

HAL Hardware Abstraction Layer - Microsoft ®

HALF DUPLEX

H.323

HBA Host Bus Adapter

HCA Host Channel Adapter

HCL Hardware Compatibility List – Microsoft 

HD Hard Disk

HDLC High Level Data Link Control

HDSL High bit rate Data Subscriber Line / High data rate Digital Subscriber Line

HERTZ / HZ Heinrich R. Hertz

HLLAPI High-Level Language Application Programming Interface

HMA High Memory Area

HMD Head Mounted Display

HON Health On the Net

HOOD Hierarchical Object Oriented Design - ADA

HP Hewlett-Packard 

HPFS High Performance File System OS/2 – IBM 

HPGL Hewlett Packard ® Graphics Language

HPPI High Performance Parallel Interface

HSRP Hot Standby Routing Protocol - Cisco ®

HSSI High Speed Serial Interface

HTML Hypertext Markup Language

HTTP Hypertext Transfer Protocol

HTTPS Hypertext Transfer Protocol Secure

Human Ear 40 Hz to 18000 Hz

Human Voice 50 Hz to 400 Hz

I2O Intelligent Input / Output

IANA Internet Assigned Numbers Authority

IARP Inverse Address Resolution Protocol

IBEX International Business EXchange

IBM International Business Machines Corporation 

ICMP Internet Control Message Protocol

ICQ " I Seek You "

ICS Internet Connection Sharing

IDC Internet Data Connector

IDE Integrated Device Electronics / Integrated Drive Electronics

IDS Intrusion Detection System

IDSL Integrated Services Digital Subscriber Line

IEEE Institute of Electrical and Electronics Engineers

IETF Internet Engineering Task Force

I-FRAME Information Frame

IF Intermediate Frequency

IFS Internet File System

IGMP Internet Group Management Protocol

IGRP Interior Gateway Protocol

IMR Interrupt Mask Register – PC

IIOP Internet Inter-ORB Protocol

IIS Internet Information Server

IISP Interim Interswitch Signaling Protocol - ATM

IKE Internet Key Exchange

IMA Inverse Multiplexing over ATM

IMAP Internet Message Access Protocol

IND$FILE IBM File Transfer program

INTERNET Internetworking

INTRANET

I/O Input / Output

IOS Internetworking Operating System - Cisco ®

IP Internet Protocol

IPCMOS

IPDU Internet Protocol Data Unit

IPHA Internet Protocol Authentication Header - IP

IPL Initial Program Load

IPNG Internet Protocol Next Generation

IPP Internet Printing Protocol

IPTC Internet Protocol Telephony Solution for Carriers – Ericsson 

IPSec Internet Protocol Security

IPV6 Internet Protocol Version 6

IPX Internet Packet Exchange – Novell 

IR Infra Red

IRB Integrated Routing and Bridging

IRDP ICMP Router Discovery Protocol

IRC Internet Relay Chat – Unix

IRCANN Internet Corporation for Assigned Names and Numbers

IRDA Infrared Data Association

IRL Inter-Repeater Links

IRQ Interrupt Service Request

ISA Industry Standard Architecture

ISAM Indexed Sequential Access Method

ISDN Integrated Services Digital Network

IS-IS Intermediate System to Intermediate System - OSI level 2 protocol

ISO International Organization for Standardization

ISP Internet Service Provider

ISPF Interactive System Productivity Family – IBM 

IT Information Technology

ITSP Internet Telephony Service Provider

ITU-T International Telecommunications Union -Telecommunication

Standardization Sector

ITV Interactive Television

IVR Interactive Voice Response

J2EE Java 2 Platform Enterprise Edition

J2SE Java 2 Specification Edition

JAIN Java Integrated Networks

JAVA Sun Microsystems 

JCL Job Control Language

JCP Java Community Process – Sun 

JCVM Java Card Virtual Machine – Sun 

JDBC Java Standard Database Connectivity

JDK Java Development Kit - Sun ®

JISC Japanese Industrial Standards Committee

JITTER

JNDI Java Native Directory Interface

JPEG Joint Photographic Experts Group

JTAPI Java Telephony Application Program Interface

JTS Java Transaction Service

JVM Java Virtual Machine

KB Keyboard

KB Kilobytes

KBPS Kilobits per second

KERBEROS

KERMIT From Kermit after the Muppet show

KHz Kilo Hertz

KMA Kernel Memory Allocation

KSH Korn Shell

KVA kilovoltampere.

L2TP Layer-Two Tunneling Protocol

LADT Local Access / Area Data Transport

LAM

LAN Local Area Network

LAP Link Access Procedure

LAPB Link Access Procedure Balanced

LAPD Link Access Procedure channel D

LAPF Link Access Procedure F - Frame Relay

LAPM Link Access Procedure channel for Modem

LAPX Link Access Procedure half-duplex

LASER Light Amplification by Stimulation of Radiation

LAT Local Address Table

LAWN Local Area Wireless Network

LBX Low-Bandwidth X

LCD Liquid Crystal Display

LCP Link Control Protocol - PPP

LDAP Lightweight Directory Access Protocol

LDCELP Low Delay Code Excited Linear Prediction

LDPA Lightweight Document Printing Application

LED Light Emitting Diode

LEN Low-Entry Networking – IBM 

LF Line Feed

LIA Liaison Inter Autocommutateur

LIFO Last In First Out

LILO Linux Boot Loader - Linux

LMI Layer Management Interface - ATM

LINUX Linus Torvalds

LL Line Layer - Sonet

LLC Logical Link Control

LMI Local Management Interface

LNB Low Noise Block Downconverter

LNM Lan Network Manager

LP Line Printer - Unix

LPI Line Per Inch

LQ Letter Quality

LQR Link Quality Report - PPP

LSA Link State Advertisements - Cisco ®

LSB Least Significant Bit

LPT1: Line Printer Terminal 1

LTO Linear Tape Open

LU Logical Unit – IBM 

LUN Logical Unit Number – SCSI

LZW Lempel-Ziv-Welch – File Compression

MAC Media Access Control

MAP Multi Access Portal – Vivendi / Vodaphone

MAPI Mail Application Programming Interface

MAN Metropolitan Area Network

MAU Media Attachment Unit or Multiple Access Unit

MB Mega Bytes

MBUS Module BUS - Sun ®

MCA Micro Channel Architecture

MCB Memory Control Bloc

MCH Memory Controller Hub – Intel 

MCI Media Control Interface

MCM Multi Media Conference Manager – Cisco 

MCR Magnetic Card Reader

MCR Minimum Cell Rate

MCS Media Convergent Server – Cisco 

MCTD Mean Cell Transfer Delay

MCU Multipoint Control Unit

MDLP Mobile Data Link Protocol

MDN Message Disposition Notification – RFC 2298

MEGA BITS M/Bits

MEGA BYTES

MEGA HERTZ

MESCH Multi - WAIS Engine for Searching Commercial Host - Internet

MET Mobile Electronic Transactions

MFC Microsoft Foundation Class

MFLOPS Million Floating-point Operation Per Second

MFM Modified Frequency Modulation

MGCP Media Gateway Control Protocol – Cisco 

MIB Management Information Base

MIDI Musical Instrument Digital Interface

MIME Multipurpose Internet Mail Extension

MIPS Millions of Instructions Per Second

MIT Massachusetts Institute of Technology

MLBA Multi Node Load Balancing Architecture

MLID Multiple Link Interface Driver

MLP Multi Link Procedure

MMX Multimedia Extension / Matrix Math Extensions - Processor

MNLB Multi Node Load Balancing

MNP Microcom Networking Protocol

MODEM Modulator / Demodulator

MOS Metal Oxide Semi-conductor

MOSS Mime Object Security Services

MOV QuickTime Movie

MPEG Motion Picture Expert Group

MPLS Multi Protocol Label Switching

MPP Massively Parallel Processing

MPP Message Posting Protocol – RFC 1204

MPPP Message Point-to-Point Protocol - RFC 1990

MPR Multi Protocol Router

MP3 MPEG1 Layer 3

MRTG Multi Router Traffic Grapher

MP3 MPEG1 Layer 3

MR Magneto-Resistive - Disk / IBM ®

MRCS Multi Rate Circuit Switching

MRJ MacIntosh Java Machine

MRTG Multi Router Traffic Grapher

MRU Maximum Receive Unit

MSB Most Significant Bit

MSCDEX Microsoft Compact Disk Extensions - Microsoft ®

MS-DOS Microsoft Disk Operating System

MSI Medium Scale Integration

MSN Microsoft Network ®

MSN Monitoring Cell Sequence Number

MSN Multi line Subscriber Numbering

MSVC Meta Signaling Virtual Channel

MTBF Mean Time Between Failures

MTA Mail Transfer Agent

MTU Maximum Transmission Unit

MUA Mail User Agents - Unix

MVS Multiple Virtual Storage – IBM 

MVS Multiple Virtual System

NAI Network Associates

NAK Negative Acknowledge

NAMP North American Numbering Plan

NARP Non-Broadcast Multiple Access Address Resolution Protocol - RFC1735

NAS Network Access Server – Microsoft 

NAS Network Attached Storage

NASDAQ National Association of Securities Dealers Automated Quotation

NAT Network Address Translation – RFC 1631

NAU Network Addressable Units – IBM 

NAUN Nearest Active Upstream Neighbor - MAC

NBAR Network Based Application Recognition – Cisco 

NCB Network Control Block

NCCF Network Communications Control Facility - IBM ®

NCP Network Control Program – IBM 

NCR National Cash Register - AT&T Global Information Solutions ® / 1991

NDIS Network Driver Interface Specification

NDS Novell Directory Services

NEC Nippon Electronic Corporation ®

NETBEUI Netbios Enhanced User Interface

NETBIOS Network Adapter Basic Input Output System

NFAS No Frame Alignment Sequence - Telephony

NFS Network File System – Unix – RFC 1813

NHDR Network Layer Header

NHRP Next Hop Resolution Protocol – X.25

NIC Network Interface Card

NiCd Nickel-Cadmium

NimH Nickel Metal Hydride

NIS Network Information Service – Unix

NLM Netware Loadable Module - Novell ®

NLQ Near Letter Quality

NMS Network Management System

NRZ Non-return to Zero

NRZI Non-return to Zero Inverted

NSA National Security Agency

NT New Technology - Microsoft ®

NTFS NT File System

NTSC National Television Systems Committee - US tv

NUA Network User Address

NUI Network User Identification - X.25 network

NURBS Non-Uniform Rational B-Spline

NVRAM Non Volatile Random Access Memory

OAIS Open Archival Information System

OC Optical Carrier

OCR Optical Character Recognition

OCX Object Linking and Embedding control

ODBC Open Database Computing Driver

ODI Open Data-Link Interface

ODR Operational Data Store

OEM Original Equipment Manufacturers

OLAP Online Analytical Processing

OLE Object Linked Embedded

OLEBD Object Linked Embedded Database

OLTP Online Transaction Processing

OMT Object Modeling Technique

OPT Open Packet Telephony

ORB Object Request Broker

ORDBMS Object Relational Database Management System

ORG Organization

OS Operating System

OSI Open Systems Interconnection

OSPF Open Shortest Path First

OSR2 Operating System Release 2 – Microsoft  / Windows 95 

OU Organization Unit

OVR Overlay - File System

P

PAD Packet Assembler-Disassembler

PAL Phase Alternate Line - TV

PAM Plug-able Authentication Modules

PAM Pulse Amplitude Modulation

PAP Password Authentication Protocol – PPP – RFC 1334

PASCAL

PAT Port Address Translation

PBX / PABX Private Automatic Branch Exchange

PC Personal Computer

PCI Peripheral Component Interconnect or Interface

PCL Printer Control Language - Hewlett Packard

PCM Pulse Code Modulation

PCMCIA Personal Computer Memory Card Internation Association

PCR Peak Cell Rate

PCVS Point to Point Switched Virtual Connections

PCX PiCture eXchange - File System Painbrush ™/ Zsoft ®

PDA Personal Digital Assistant

PDC Primary Domain Controller – Windows 

PDF Portable Document Format file / Package Definition Files

PDH Plesiochronous Digital Hierarchy

PDT Printer Definition Tables

PDU Packet Data Unit

PDU Protocol Data Unit

PERL Practical Extraction and Report Language

PEM Privacy Enhanced Mail - RFC 1421 to 1424

PERT Program Evaluation and Review Technic

PGP Pretty Good Privacy

PHP Hypertext Preprocessor

PHY Physical Layer

PIC Picture File
PID Process Identification Number - Unix

PIM Personal Information Manager

PIM Protocol Independent Multicast

PIN Personal Identification Number

PINE Program for Internet News and E-mail

PING Packet Internet Gopher

PIXEL Picture Cell

PKI Public Key Information

PLAR Private Line Auto Ringdown

PLC Power Line Communication

PLMN Public Land Mobile Network

PNG Portable Network Graphics

PPNI Private Network-to-Network Interface - ATM

PNP Plug And Play

POL Path Overhead Layer - Sonet

POP3 Post Office Protocol Version 3

POP Point of Presence / Post Office Protocol

POSIX Portable Operating System for Unix

POST Power-On Self Test

POTS Plain Old Telephone Service

PPDU Presentation Protocol Data Unit

PPGA Plastic Grid Pin Array – Intel 

PPM Page(s) Per Minute

PPP Pay Per View

PPP Point to Point Protocol

PPSN Public Packet-Switched Network

PPTP Point to Point Tunneling Protocol

PQA Palm Query Application

PRI Primary Rate Interface - ISDN

PRISM Parallel Reduced Instruction Set Multiprocessing

PRML Partial Response Maximum Likehood

PROFS Professional Office System

PROM Programmable Read Only Memory

PSTN Public Switched Telephone Networks

PT Payload Type - ATM

PTE Path Terminating Equipment

PTR Pointer Reverse

PU Physical Unit – IBM 

PVC Permanent Virtual Circuit

PVCS Polytron Version Control Program

PVPC Permanent Virtual Path Connection – ATM

PWD Print Working Directory - Unix

PXE Pre-boot Execution Environment

QAM Quadrature Amplitude Modulation

QBE Query By Example - Database

QBIC Query By Image Content - IBM ®

QLLC Qualified Logical Link Control

QOS Quality Of Service

QPSK Quadrature Phase-Shift Keying

QPSX Queue Packet and Synchronous Circuit Exchange

QSIG

RACF Resource Access Control Facility

RADIUS Remote Authentication Dial-in User Service

RAID Redundant Array of Independent Disks

RADSL Rate Adaptive Asymmetric Digital Subscriber Line

RAM Random Access Memory

RANDOM
RARP Reverse Address Resolution Protocol

RAS Remote Access Service – Microsoft 

RBS Robbed-Bit Signaling

RD Receive Data

RDBMS Remote Data Base Management System

RDNIS Redirected Dial Number Id Service

RDRAM Rambus Dynamic Random Access Memory

RDS Radio Digital System

RED Random Early Detection - Cisco ®

REL Release Message

RET Resolution Enhancement Technology - Hewlett-Packard ®

REXX Restructured Extended Executor – IBM ®

RFC Request For Comments

RGB Red Green Blue

RI Ring Indicator - Modem

RI Routing Information

RIC Real Time Interface Co-processor - IBM  or RTIC

RIM Research In Motion

RIMM Rambus In-line Memory Modules

RIP Routing Information Protocol

RISC Reduced Instruction Set Computer

RJ-11 /12 / 45 Registered Jacks

RLOGIN Remote Login - Unix

RLP Radio Link Protocol

RM cells Rate Management cells - ATM

RMON Remote Monitor

RMS Root Mean Square

RNR Receive Not Ready

ROM Read Only Memory

Router
RPC Remote Procedure Call

RR Receiver Ready

RRAS Routing and Remote Access Service

RRQ Registration Request

RSA Rivest-Shamir-Adelman

RSH Remote Shell - Unix

RSRB Remote Source Route Bridging – Cisco 

RSVP Resource reSerVation Protocol

RS-232

RTC Real Time Clock

RTCP Real-Time Transport Control Protocol

RTIC Real Time Interface Co-processor - IBM 

RTF Rich Text Format

RTM Response Time Monitor

RTP Real Time Protocol - RFC 1889

RTPM Real Time Performance Monitor

RTS Request To Send

RTSP Real-Time Streaming Protocol

RU Request Unit – IBM 

SA Source Address

SAA Systems Application Architecture – IBM 

SAM Security Access Manager – Windows 

SAM Sequential Access Method

SAM System Activity Monitor - Unix

SAN Storage Area Network

SANS Institute System Administration Networking and Security ®

SAP Service Access Point – IBM 

SAP Systems, Applications, and Products in Data Processing

Systeme und Anwendungs Programme in der Datenverarbeitung

SCO The Santa Cruz Operation 

SCP Service Control Point

SCSI Small Computer Standard Interface

SDDI Shielded Distributed Data Interface - FDDI

SDH Synchronous Digital Hierarchy

SDK Software Development Kit - Microsoft ®

SDLC Synchronous Data Link Control

SDMI Secure Digital Music Interactive

SDRAM Synchronous Dynamic Random Access Memory

SDSL Symmetric Asymmetrical Digital Subscriber Line

SET Secure Electronic Transaction

SG Signal Ground - Modem

SGMP Simple Gateway Monitoring Protocol - RFC 1028

SH Bourne Shell

SID Security Identifier – Microsoft 

SID Signaling Identifier

SIM Subscriber Identify Module

SIMD Simple Instruction Multiple Data – Intel 

SIMM Single In-line Memory Module

SITA Societe Internationale de Telecommunications Aeronautiques

SL Section Layer - Sonet

SLA Service Level Agreement

SLARP Cisco Serial Line Address Resolution Protocol

SLIP Serial Line Internet Protocol – RFC 1055

SLR Scalable Linear Tape - Tandberg Data®

SMC Sleep Mode Connection

SMDI Simple Message Desk Interface – Cisco 

SMIT System Management Interface Tool - Unix

SMP Symmetric Multiprocessing - Microsoft ®

SMS Short Message Services

SMS Systems Management Server – Microsoft 

SMT Station Management

SMTP Simple Mail Transfer Protocol – RFC 821

SNA System Network Architecture – IBM 

SNAP Sub Network Access Protocol

SNMP Simple Network Management Protocol

SNPP Simple Network Paging Protocol - RFC 1861

SNTP Simple Network Time Protocol - RFC 2030

SOAP Simple Object Access Protocol

SOH Section Overhead

SOHO Small Office-Home Office

SOI Silicon On Insulator – IBM 

SONET Synchronous Optical Networks

SPARC Scalable Processor Architecture Reduced instruction set Computer – Sun 

SPE Synchronous Payload Envelope - Sonet

SPID Service Protocol Identifier - ISDN

S/PDIF Sony ® Philips ® Digital Interface

SPP Standard Parallel Port

SPX Sequenced Packet Exchange

SQL System Query Language

SR Source Routing

SRPI Server Requester Programming Interface – IBM 

SRT Source Routing Transparent

SRTS Synchronous Residual Time Stamp

SS7 Signaling System Number 7

SSCP System Services Control Point – IBM 

SSH Secure Shell

SSL Secure Socket Layer

SSP System Query Language Server Standard – Microsoft 

STE Spanning Tree Explorer

STM Synchronous Transport Module

STP Shielded Twisted Pair - cable

STP Spanning Tree Protocol

STS Synchronous Transport Signal – Sonet

STSPP Synchronous Transport Signal Payload Pointer - Sonet

SU Subscriber Unit

SVC Switched Virtual Circuit

SVG Scalable Vector Graphics

SVGA Super Video Graphics Array

SYNCHRONOUS

SYSOP System Operator

TAC Technical Assistance Center – Cisco 

TAD Technical Audio Device

TAPI Telephony Application Program Interface

TB Terra Bytes

TCA Target Channel Adapter

TCO Total Cost of Ownership

TCP Transmission Control Protocol

TD Transmitted Data

TDM Time Division Multiplexing

TDMA Time Division Multiple Access

TELNET Telecommunications Network Protocol – RFC 854

TFLOPS Tera Floating-point Operations Per Second

TFT Thin Film Transistor

TFTP Trivial File Transfer Protocol

TI Texas Instruments ®

TIC Token-Ring Interface Coupler

TIFF Tagged Image File Format – Aldus 

TLS Transport Level Security

TOS Type Of Service

TPF Transaction Processing Facility - IBM ®

TRUNK

TSAP Transport Service Access Point

TSAPI Telephony Services Api

TSI Transmitting Subscriber Information

TSO Time Sharing Option

TSR Terminate and Stay Resident

TTL Time To Live

TTL Transistor -Transistor Logic

TTY Teletype

TUI Telephony User Interface

TWAIN Technology Without An Interesting Format

T1

UA Unnumbered Acknowledgement

UART Universal Asynchronous Receiver Transmitter

UBR Unspecified Bit Rate - ATM

UDB Universal Database

UDP User Datagram Protocol

UI User Interface

UID User Identification

UIO Universal I/O serial port - Cisco ®

U-LAW 64 Kbps G.711 - Voice

UML Unified Modeling Language

UMTS Universal Mobile Telecommunications Systems

UNC Universal Naming Convention

UNIX Uniplex Information and Computer Services

UONE Unified Open Network Exchange – Cisco 

UPS Uninterrupted Power Supply

URI Uniform Resource Identifier – RFC 1630

URL Uniform Resource Locators – RFC 1738

URN Uniform Resource Name – RFC 1737

USART Universal Synchronous Asynchronous Receiver / Transmitter

USCW Uncacheable Speculative Write Combining

USPARC Ultra Scalable Processor Architecture Reduced instruction set Computer

USB Universal Serial Bus

USOC Universal Service Order Codes

UTP Unshielded Twisted Pair - cable

V.24 24 Pins serial connector

VB Visual Basic

VBR Variable Bit Rate

VC Virtual Circuit

VCA Voltage Controlled Amplifier

VDM Virtual Device Metafile

VDSL Very High Data Rate Digital Subscriber Line

VESA Video Electronics Standards Association

VGA Video Graphics Array – IBM 

VHF Very High Frequency

VIC Voice Interface Card

VISP Virtual Internet Service Providers

VLAN Virtual Lan Area Network

VLM Virtual Loadable Module - Novell ®

VLSI Very Large Scale Integration

VM / CMS Virtual Machine / Conversational Monitor System – IBM 

VMS Virtual Machine / Storage - Os DEC for Vax machines

VP Virtual Path - ATM

VPC Virtual Path Connection – ATM

VPCI Virtual Path Connection Identifier - ATM

VOFR Voice Over Frame Relay

VOIP Voice Over IP

VPN Virtual Private Network

VRAM Volatile Random Access Memory

VRML Virtual Reality Modeling Language

VSAM Virtual Storage Access Method

VTAM Virtual Telecommunications Access Method – IBM 

VTN Virtual Telephony Network

VTSP Voice Telephony Service Provider

WAN Wide Area Network

WAP Wireless Application Protocol

WAS Web Attached Storage

WAV Waveform sound - Microsoft

WDM Wavelength Division Multiplexer

WDM Win32 Driver Model - Microsoft ®

WEB

WFQ Weighted Fair Queuing – Cisco 

WINS Windows Internet Name Service

WMF Windows Metafile

WML Wireless Markup Language

WORM Write Once Read Many

WRED Weighted Random Early Detection - Cisco ®

WRR Weighted Round Robin – Cisco 

WSL Wireless Markup Language

WTLS Wireless Transport Layer Security

WTS Wireless Transport Security

WWW World Wide Web

W3C World Wide Web Consortium

WYSIWYG What You See Is What You Get

X
X.21

X.25

X.32

XGA Extended Graphics Array – IBM 

XID Exchange Identification – IBM 

XML Extensible Markup Language

XMS Extended Memory Specification

XNS Xerox  Network Services

XOT X.25 Over TCP-IP - RFC 1613

X-OFF Exchange OFF - Modem

X-ON Exchange ON - Modem

XOT X.25 Over TCP – Cisco 

XSL Extensible Stylesheet Language

XTP Express Transport Protocol

Y-Modem

Z-Modem