Common Acronyms

Below is a collection of acronyms commonly used within Cisco, contact center environments, and within this Help Center:

10GE – 10 Gigabit Ethernet

AAA – authentication, authorization, and accounting

AAL5 – ATM adaptation layer 5

ABM – asynchronous balanced mode

ABR – Area Border Router

AC – alternating current

ACE – Allegro Crypto Engine

ACIP – ATM Cable Interface Processor

ACK – acknowledgment

ACL – access control list

ACO – alarm cutoff

ACTLU – activate logical unit

ACTPU – activate physical unit

ADSL – asymmetric digital subscriber line

AFI – Address Family Identifier

AH – Authentication Header

AIC – Alarm Interface Controller

AIM – advanced interface module

AIM – Advanced Integration Module

AIP – ATM Interface Processor

AIS – Alarm indication

ALC – ATM line card

ALPS – Airline Product Set

AM – account managers

AMD – Advanced Micro Devices

AMD – answering machine detection

ANR – Automatic Network Routing

ANSI – American National Standards Institute

ANY-PHY – Any physical layer-data link layer

AP – access point

AP – authentication proxy

AP – account partners

API – application programming interface

APING – APPC Ping

APN – access point name

APPC – Advanced Program-to-Program Communications

APPN – Advanced Peer-to-Peer Networking

APS – automatic protection switching

AQD – average queue depth

ARAP – AppleTalk Remote Access Protocol

ARB – Adaptive Rate-Based

ARP – Address Resolution Protocol

ARQ – automatic repeat request

AS – autonomous system

ASCU – agent-set control unit

ASIC – application-specific integrated circuit

ASP – ATM switch processor

ATA – Advanced Technology Attachment

ATA – Analog Telephone Adaptor

ATF – area to free

ATM – Asynchronous Transfer Mode

AToM – Any Transport over MPLS

AURP – AppleTalk Update-Based Routing Protocol

AutoRP – Auto-Rendezvous Point

AVL – approved vendor list

BAP – Bandwidth Allocation Protocol

BB – broadband

BBI – begin bracket indicator

BCS – business critical solution

BERT – bit error rate tester

BFR – Bigger, Faster Router

BFRP – big fast route processor

BGP – Border Gateway Protocol

BGPPA – Border Gateway Protocol Policy Accounting

BIC – backplane interface card

BIDI – bidirectional bus

BIND – Berkeley Internet Name Domain

BIP – bit interleaved parity

BIS – Broadband Interface Shelf

BLLI – Broadband Low Layer Information

BMA – Buffer Management ASIC

BOOM – 10BASE-T Ethernet LAN interface card

BOOTP – Bootstrap Protocol

BPDU – bridge protocol data unit

BPI – baseline privacy interface

BPVC – Bridged Permanent Virtual Circuit

BRI – Basic Rate Interface

BRF – Bridge Relay Function

BSC – Binary Synchronous Communications

BSS – Business Support System

BSTUN – Block Serial Tunnel

BTU – British Thermal Unit

BUS – broadcast-and-unknown server

CA – certification authority

CAIM – Compression Advanced Interface Module

CAM – Content-addressable Memory

CAMR – Cisco Access Metro Router

CAS – channel-associated signaling

CASA – Cisco Appliance and Services Architecture

CBAC – Context-Based Access Control

CBC – Cell Bus Controller

CBI – Cell Bus Interface

CBus – CiscoBus

CBWFQ – Class Based Weighted Fair Queueing

CCA – Common Configuration Architecture

CCAPI – call control API

CCB – call control block

CCB – configuration control block

CCM – Cisco Configuration Manager

CCMS – Computing Center Management System

CCO – Cisco Connection Online

CCW – channel command word

CDI – Common Driver Interface

CDL – Converged Data Link

CDM – cable data modem

CDP – Cisco Discovery Protocol

CDR – clock and data recovery

CE – certificate enrollment

CEB – Common EMS Base

CEBI – conditional end bracket indicator

CEF – Cisco Express Forwarding

CES – circuit emulation service

CET – Cisco Encryption Technology

CF – Checkpoint Facility

CFI – Common Flash Interface

CGMP – Cisco Group Management Protocol

CGX – CryptoGraphics eXtensions

CHAP – Challenge Handshake Authentication Protocol

cHPI – compact host port interface

CI – connection identifier

CICS – Customer Information Control System

CIP – Channel Interface Processor

CIR – committed information rate

CIS – Card Information Services

CIU – Communication Interface Unit

CLAW – Common Link Access for Workstations

CLI – command-line interface

CLNS – Connectionless Network Service

CLS – Cisco link services

CLSI – Cisco link services interface

CMCC – Cisco Mainframe Channel Connection

CMNS – Connection Mode Network Service

CMPC – Cisco Multipath Channel

CMTS – cable modem termination system

CNR – Cisco Network Registrar

CNOS – change number of sessions

CNS – Cisco Networking Services

CNSP – Complete Number Sequence PDU

COAPS – Count of APS Switchovers

Codec – coder-decoder

CoS – class of service

CoSQ – Class of Service Queues

COT – continuity testing

CP – control point

CP – coprocessor

CPA – Channel Port Adapter

CPE – customer premises equipment

CPI – common part indicator

CPI-C – common programming interface for communications

CPM – Combination Port Module

CRC – cyclic redundancy check

CRF – Concentrator Relay Function

CRL – certificate revocation list

cRTP – compressed Real-Time Protocol

CRV – call reference value

CSA – compression service adapter

CSAR – Cisco Cell Segmentation and Reassembly

CSC – clock switch card

CSG – Content Services Gateway

CSI – called subscriber identification

CSM – call switching mode

CSM – call switching module

CSNA – Cisco SNA

CSNP – Complete Sequence Number PDU

CSU – channel service unit

CTC – Cisco Transport Controller

CTL – Certificate Trust List

CTRC – Cisco Transaction Connection

CTI - Computer Telephony Interface

CTS – Clear To Send

CUCDM – Cisco Unified Communication Domain Manager

CV – Cisco View

CVP – Customer Voice Portal

CWAN – Constellation WAN

CWTLC – Constellation Wan Toaster Line Card

CyBus – Cisco Extended Bus

DAE – data aggregator end

DBus – diagnostic bus

DC – direct-connect

DC – direct current

DCD – data carrier detect

DCE – data communications equipment

dCEF – distributed Cisco Express Forwarding

DDOS – distributed denial of service

DDR – dial-on-demand routing

DDSM – Digital Data Services Manager

DECnet – Digital Equipment Corporation network

DEMUX – demultiplexer

DFC – dial feature card

DFP – Dynamic Feedback Protocol

DFRAC – Dual Framer and RAC

DHCP – Dynamic Host Configuration Protocol

DHCPv6 – Dynamic Host Configuration Protocol, version 6

DIB – Directory Information Base

DIP-4 – 4-bit Diagonal Interleaved Parity

DLC – data-link connection

DLC – data-link control

DLCI – data-link connection identifier

dLFI – Distributed Link Fragmentation and Interleaving

dLFIoATM – Distributed Link Fragmentation and Interleaving over ATM

dLFIoFR – Distributed Link Fragmentation and Interleaving over Frame Relay

DLR – designated local retransmitter

DLSw – data-link switching

DLU – dependent logical unit

DLU – destination logical unit

DLU – dynamic logical unit

DLUR – dependent logical unit requester

DLUS – dependent logical unit server

DM – dense mode

DM – disconnect mode

DMA – direct memory access

DMAC – destination MAC

DML – distributed multilink

DMLP – Distributed Multilink Point-to-Point Protocol

DN – dial number

DNIS – dialed number identification service

DNS – Domain Name Server

DNS – Domain Name Service

DNS – Domain Name System

DOCSIS – Data-over-Cable Service Interface Specifications

DOI – domain of interpretation

DoS – denial of service

DPRAM – dual-port RAM

DR – Designated Router

DR – dynamic replenishment

DRAM – dynamic RAM

DRDA – Distributed Relational Database Architecture

DRiP – Duplicate Ring Protocol

DRP – Director Response Protocol

DRQ – Direct memory access Receive Queue

DS – dial shelf

DSA – delayed stop accounting

DSC – dial shelf control

DSC – dial shelf controller

DSCP – differentiated service code pointer

DSI – dial shelf interconnect

DSI – dial shelf interface

DSIP – Dial Shelf Interconnect Protocol

DSL – digital subscriber line

DSLAM – digital subscriber line ATM multiplexer

DSMP – Distributed Stream Media Processor

DSP – digital signal processor

DSP – Domain Specific Part

DSP – digital signal processor

DSPFARM – digital signal processor farm

DSPM – digital signal processor module

DSPRM – Digital Signal Processor Resource Manager

DSPU – downstream physical unit

DSR – data set ready

DSU – data service unit

DSU – digital service unit

DTE – data terminal equipment

DTP – Dynamic Trunking Protocol

DTQ – Direct memory access Receive Queue

DTR – data terminal ready

DVMRP – Distance Vector Multicast Routing Protocol

E1T1 – E1 line or T1 line

EADI – Extended Availability Drop and Insert

EAIM – Encryption AIM

EAP – Extensible Authentication Protocol

EAPoUDP – Extensible Authentication Protocol over User Datagram Protocol

EARL – enhanced address recognition logic

EC – EtherChannel

ECA – ESCON Channel Adapter

ECC – error-correcting code

ECC – Error-Check Code

ECC – error checking and correction

ECM – Extensible Call Model

ECM – External Control Memory

EEM – Embedded Event Manager

EEPROM – electronically erasable programmable read-only memory

EGP – exterior gateway protocol

EHSA – enhanced high system availability

EID – endpoint identifier

EIGRP – Enhanced Interior Gateway Routing Protocol

EIO – Elastic I/O

ELAN – emulated LAN

ENUM – enumeration

ENVM – Constellation WAN Environmental Monitor

EOBC – Ethernet Out-of-Band Channel

EOC – embedded operations channel

EOF – end-of-frame

EOIR – enhanced online insertion and removal

EoMPLS – Ethernet over MPLS

EOU – Extensible Authentication Protocol over User Datagram Protocol

EPM – External Packet Memory

ESCON – Enterprise System Connection

ESMP – Even Simpler Management Protocol

ESP – Extended Services Processor

ESP – Extended Services Platform

ESW – Ethernet Switch

ESWILP – Ethernet Switch with Inline Power

ESYS – Undefined

ETM – Enhanced Timing Module

EWT – estimated wait time

EXAR – Chip manufacturer

FAQ – frequently asked question

FB – feature board

FBB – fast back-to-back

FBB – from backplane buffer

FCFS – First Come First Served

FCIT – Fiber Channel Idle Time

FC-PFQ – feature card per-flow queueing

FCPA – Fiber Channel Port Adapter

FCS – frame check sequence

FDDI – Fiber Distributed Data Interface

FDL – Facility Data Link

FDM – frequency-division multiplexing

FE – Fast Ethernet

FEC – Fast EtherChannel

FECPM – Fast Ethernet Combo Port Module

FI – format indicator

FIA – Fabric Interface ASIC

FIB – forwarding information base

FIFO – first-in, first-out

FIR – Finite Impulse Response

FM – fault monitoring

FMSP – Fax Media Services Provider

FPGA – field-programmable gate array

FPI – Forwarding Path Identifier

FQDN – fully qualified domain name

FQPCID – fully qualified procedure correlation identifier

FREEDM – Frame Engine and Data Link Manager

FRMR – Frame Reject

FRoM – Frame Relay over MPLS

FRoMPLS – Frame Relay over MPLS

FRR – Fast ReRoute

FRU – field-replaceable unit

FSIP – Fast Serial Interface Processor

FSM – finite state machine

FTBB – from/to backplane buffer

FTP – File Transfer Protocol

GBIC – Gigabit Interface Converter

GC – global configuration

GDS – general data stream

GE – Gigabit Ethernet

GEFC – Gigabit Ethernet/Fiber Channel

GEIP – Gigabit Ethernet Interface Processor

GGSN – gateway GPRS support node

GKTMP – Gatekeeper Transaction Message Protocol

GLBP – Gateway Load Balancing Protocol

GLC – gigabit line card

GP – Global Pointer

GPRS – general packet radio service

GRP – gigabit route processor

GSN – GPRS support node

GSR – Internet router

GT95K – Undefined

GTF – Generalized Trace Facility

GTP – GPRS tunneling protocol

GULF – GULF-2488 ASIC

HA – High Availability

HA – Home Agent

HAL – Halcyon

HAPX – Hardware Assisted Packet Classification

HCS – Hosted Collaboration Solution

HDLC – High-Level Data Link Control

HDS – Historical Data Server

HDV – High Density Voice

HDX – half-duplex

HEC – header error control

HERA – Undefined

HGW – home gateway

HMAC – hash message authentication codes

HMS – Home Media Server

HPI – Host Port Interface

HPR – High-Performance Routing

HQF – Hierarchical Queuing Framework

HSA – high system availability

HSRP – Hot Standby Router Protocol

HSSI – High Speed Serial Interface

HT-FPGA – Hyper Transport Field-Programmable Gate Array

HWAF – Hardware Address Filtering

HWIC – High-Speed WAN Interface Card

HWICD – High-Speed WAN Interface Card, double-wide

HWIDB – hardware interface descriptor block

I2C – Inter-Integrated Circuit

IBGP – internal BGP

IBL – Input Buffer Logic

IBOC – in-band bit-oriented code

ICC – Inter Card Communication

ICC – Interface Controller Card

ICM – Intelligent Contact Management

ICMP – Internet Control Message Protocol

ICPIF – Calculated Planning Impairment Factor

ICR – Routing Controls (formerly icRoute)

ICS – Integrated Communication System

IDAP – Internet Data Access Presentation

IDB – interface descriptor block

IDPROM – Identification PROM

IDS – Internal Data Services

IDT – Integrated Digital Terminal

IDU – indoor unit

IE – information element

IEEE – Institute of Electrical and Electronics Engineers

IETF – Internet Engineering Task Force

IF – intermediate frequency

IGMP – Internet Group Management Protocol

IGRP – Interior Gateway Routing Protocol

IIC – Undefined

IIF – Input interface

IIH – IS to IS Hello PDU

IIN – Undefined

IKE – Internet Key Exchange

ILMI – Integrated Local Management Interface

ILP – inline power

ILPM – inline power module

IMA – inverse multiplexing over ATM

IMSI – international mobile subscriber identity

IOB – Undefined

IP – Internet Protocol

IPC – interprocess communication

IPDC – Internet Protocol device control

IPDLC – IP data link connection

IPE – Inter-PRE Ethernet

IPG – Inter Packet Gap

IPHC – IP Header Compression

IPM – Cisco Internetwork Performance Monitor

IPPCP – IP Payload Compression Protocol

IPRM – IP Router Manager

IPS – IP Storage

IPSec – IP Security

IPT – Internet Protocol Telephony

IPv6 – IP version 6

IPX – Internetwork Packet eXchange

ISA – Integrated Services Adapter

ISAKMP – Internet Security Association and Key Management Protocol

ISDN – Integrated Services Digital Network

ISE – Internet Services Engine

IS-IS – Intermediate System-to-Intermediate System

ISL – Inter-Switch Link

ISR – intermediate session routing

ISRHOG – Interrupt Service Routine HOG

ISSU – In-Service Software Upgrade

IST – Internal Spanning Tree

IVR – interactive voice response

IXP – Internet Exchange Point

KB – kilobyte

L2 – Layer 2

L2F – Layer 2 Forwarding

LAC – L2TP access concentrator

LACP – Link Aggregate Control Protocol

LAIS – SONET Line level Alarm Indication Signal

LANCE – Local Area Network Controller Ethernet

LANE – LAN Emulation

LAPB – Link Access Procedure, Balanced

LAT – local-area transport

LC – line card

LCATM – Label controlled ATM

LCB – Line Control Block

LCC – Line card Configuration Coordinator

LCD – liquid crystal display

LCDOS – line card operating system software

LCI – local channel identifier

LCN – logical channel number

LDAP – Lightweight Directory Access Protocol

LDLC – LocalDirector link control

LDN – local directory number

LDP – Label Distribution Protocol

LEC – LANE Client

LECS – LANE Configuration Server

LED – light-emitting diode

LEN – low-entry networking

LES – LANE Server

LFD – Label Forwarding Database

LFSID – local-form session identifier

LIR – link incident report

LIU – line interface unit

LLC – logical link control

LLC2 – Logical Link Control, type 2

LLD – low level design

LMI – Local Management Interface

LNM – LAN Network Manager

LNS – L2TP network server

LOF – Loss of Frame

LOS – Loss of Signal

LPD – line printer daemon

LPDMS – live person detect module

LRC – line card redundancy controller

LRJ – location rejection

LRQ – location request

LS – LightStream

LSA – link-state advertisement

LSD – label switching database

LSIPC – LightStream interprocess communication

LSP – label switch path

LSP – link-state packet

LSP – Link-State PDU

LSS – LightStream switching

LU – logical unit

LU6.2 – logical unit type 6.2

LVC – label switched controlled virtual circuits

LWAPP – Lightweight Access Point Protocol

LYRA – Constellation+ Advanced Forwarding Engine Layer2

MAC – Media Access Control

MAR – Midrange Access Routers

MARS – Multicast Address Resolution Server

MATM – MAC Address Table Manager

MAU – media attachment unit

MAX – maximum

MB – megabyte

MBE – multiple-bit error

MBRI – Multi-BRI

MBRI – Multiport Basic Rate Interface

MBus – maintenance bus

MCD – Undefined

MCNS – Multimedia Cable Network System Partners, Ltd.

MCOM – Microcom carrier card

MCDMA – Multi-Channel DMA

MCSC – Multi-Channel Serial Controller

MD5 – message digest 5

MDB – Multicast Descriptor Block

MDL – maintenance data link

MDRR – Modified Deficit Round Robin

MDS – multicast distributed switching

MDSS – Multicast Distributed Shortcut Switching

MDT – multicast distribution tree

MEMD – memory device

MFD – Multicast Fast Drop

MFE – Multi-port Fast Ethernet

MFI – MPLS forwarding infrastructure

MFIB – Multicast Forwarding Information Base

MGCP – Media Gateway Control Protocol

MGID – Undefined

MIB – Management Information Base

MIB/SMT – Management Information Base/Station Management

MIC – media interface connector

MICA – Modem ISDN channel aggregation

MID – Multiplex ID

MIDB – multicast interface data block

MII – media-independent interface

MLD – Multicast Listener Discovery

MLP – Multilink Point-to-Point Protocol

MLPPP – Multilink Point-to-Point Protocol

MLS – multilayer switching

MLSM – multi-layer switching for multicast

MLTG – multilink trunk group

MMAP – memory map

MMC – Undefined

MMI – Modem Management Interface

MMLS – multicast multilayer switching

MNCNS – Multimedia Cable Network System Partners, Ltd.

MNP4 – Microcom Networking Protocol 4

MP – Multilink Protocol

MPC – MultiPath Channel

MPC – Multiprotocol-over-ATM client

MPLS – Multiprotocol Label Switching

MPOA – Multiprotocol over ATM

MPPE – Microsoft Point to Point Encryption

MPS – Multiprotocol-over-ATM server

MQC – Modular Quality of Service (QoS) command line interface (CLI)

MRIB – Multicast Routing Information Base

MRP – Multiservice Routing Processor

MPT – Ministry of Posts and Telecommunications

mroute – Multicast route

MRW – Undefined

MS – Management Services

MS – mobile subscriber

MSC – Modular Services Card

MSDP – Multicast Source Discovery Protocol

MSFC – Multilayer Switch Feature Card

MSP – Media Service Provider

MSR – Multiservice Switch Router

MSS – maximum segment size

MST – Multiple Spanning-Tree Protocol

MSTOO – multiple spanning tree root

Mtree – matings tree

MTU – maximum transmission unit

MURIB – Multicast Unicast Routing Information Base

MVIP – Versatile Interface Processor

MW – Undefined

MWAM – Multi-Processor WAN Application Module

Mx – Mueslix

NAK – negative acknowledgment

NAM – Network Analysis Module

NAS – network access server

NAT – Network Address Translation

NBAR – network-based application recognition

NBP – Name Binding Protocol

NCE – network connection endpoint

NCP – Network Control Program

NCP – Network Control Protocol

NEAT – E1 and T1 processor

NFAS – Non-Facility Associated Signaling

NHDR – Network Layer Header

NHRP – Next Hop Resolution Protocol

NHS – Next Hop Server

NIM – network interface module

NIP – Nitro Interconnect Protocol

NLP – network-layer packet

NLSP – NetWare Link Services Protocol

NM – network module

NM-HD – high density network module

NME – Network Management Ethernet

NMI – nonmaskable interrupt

NMP – Network Management Processor

NMS – network management system

NMVT – network management vector transport

NNI – Network-to-Network Interface

NNS – network node server

NPE – network processing engine

NRM – normal response mode

NRP – Network Routing Processor

NRP – node route processor

NSAP – network service access point

NSDB – Network Security Database

NSE – network services engine

NSF – Non-stop forwarding

NSP – Network Switch Processor

NSP – node switch processor

NTP – Network Time Protocol

NVRAM – nonvolatile RAM

OAM – Operation, Administration, and Maintenance

OBL – Output Buffer Logic

OC – Optical Carrier

ODU – outdoor unit

OER – Optimized Edge Routing

OFC – open fiber control

OIF – Output interface

OIR – online insertion and removal

ONS – Optical Networking Systems

OOBP – out-of-band port

OOD – Online Offline Diagnostics

OOS – out of service

ORF – outbound route filter

OSCP – Optical Supervisory Channel Protocol

OSM – Optical Services Module

OSP – Open Settlements Protocol

OSPF – Open Shortest Path First

OSS – Operations Support System

OU – organizational unit

PA – port adapter

PAD – packet assembler/disassembler

PAgP – Port Aggregation Protocol

PAM – port adapter module card

PAM – pulse amplitude modulation

PAN – 4-Port and (8+1) Port ESWILP HWIC

PAP – Password Authentication Protocol

PARAM1 – Undefined

PARAM2 – Undefined

PASCB – port adapter system control block

PASV – passive mode FTP

PBP – packet-by-packet

PC – program counter

PCA – Parallel Channel Adapter

PCF – Packet Control Function

PCF – Profile Configuration File

PCI – protocol control information

PCID – procedure correlation identifier

PCM – pulse code modulation

PCMCIA – Personal Computer Memory Card International Association

PCR – peak cell rate

PCS – Packaged Collaboration Solutions

PDP – policy decision point

PDSN – Packet Data Serving Node

PDU – protocol data unit

PEMF – Power Entry Module and Filter

PF – protocol filtering

PG – peripheral gateway

PGM – Pragmatic General Multicast

PHAD – Physical Layer Interface Module (PLIM) header add-drop ASIC

PHY – physical layer interface

PIC – Peripheral Interface Controller

PIC – point in call

PIE – protocol information element

PIF – Packet Input FIFO

PIM – Protocol Independent Multicast

PIM-SM – Undefined

PIMv2 – Protocol Independent Multicast version 2

PIU – PCM Interface Unit

PKCS – Public Key Cryptographic Standards

PKI – public key infrastructure

PLD – programmable logic device

PLIM – Physical Layer Interface Module

PLU – primary logical unit

PLX – PCI to local bus bridge vendor

PM – port management

PMA – Packet Memory Access

PMC – PCI Mezzanine Card

PMON – Performance Monitor

PNNI – Private Network-Network Interface

PNSP – Partial Number Sequence PDUs

POD – point of distribution

POE – Power Over Ethernet

PoS – Packet over SONET

PoS – Packet over SONET/SDH

POST – power-on self-test

POT1E1 – Packet Over T1 E1

POTS – plain old telephone service

PPC – primary point code

PPP – Point-to-Point Protocol

PQUICC – Quad Integrated Communications Controller

PRE – Performance Routing Engine

PRI – Primary Rate Interface

PROM – programmable read-only memory

PRP – Performance Route Processor

PS – professional services

PSA – Packet Switching ASIC

PSC – processor and switch card

PSM – Protection Switch Module

PSNP – Partial Sequence Number PDU

PSR – performance, stability, and reliability

PSTN – public switched telephone network

PTB – Peer Transaction Bus

PTM – Packet Transfer Mode

PU – physical unit

PU – 2.0 Physical Unit type 2.0

PU – 2.1 Physical Unit type 2.1

PVC – permanent virtual circuit

PVC – permanent virtual connection

PVDM – Packet Voice DSP Module

PVID – Port VLAN ID

PVP – permanent virtual path

PVST+ – Per-VLAN Spanning Tree

PXF – Parallel eXpress Forwarding

PXM – Processor Switching Module

QA – queue and accumulator

QEM – QEM driver

QLLC – Qualified Logical Link Control

QM – QoS manager

QMAC – Quad Token Ring Media Access Controller ASIC

QoS – quality of service

QSTAT – Undefined

RA – registration authority

RAC – Resource Availability Confirm

RAC – Ring Access Controller

RADIUS – Remote Authentication Dial-In User Service

RARP – Reverse Address Resolution Protocol

RAS – Registration, Admission, and Status

RAS – remote access server

RBCP – Router Blade Configuration Protocol

RBD – receive buffer descriptor

RBS – Robbed-Bit Signaling

RC – Routing Controls

RCP – remote copy protocol

RDB – relational database

RE – Undefined

RED – Undefined

REQACTPU – request to activate a physical unit

REQDACTPU – request to deactivate a physical unit

REQ(D)ACTPU(RSP) – Route Switch Processor request to activate or deactivate a physical unit

REXEC – remote execution

RF – radio frequency

RF – Redundancy frequency

RIB – Routing Information Base

RIM – Undefined

RIP – Routing Information Protocol

RISC – reduced instruction set computing

RJE – remote job entry

RLDRAM – Undefined

RLM – Redundant Link Manager

RMON – Remote Network Monitoring

RNR – receive not ready

ROM – read-only memory

RP – Route Processor

RPA – Resource Pool Allocation

RPC – Remote Procedure Call

RPF – Reverse Path Forwarding

RPM – Route Processor Module

RPM – Resource Pool Management

RPMXF – Route Processor Module, express forwarding

RPR – Route Processor Redundancy

RPR+ – Route Processor Redundancy plus

RPS – Ring Parameter Server

RR – receive ready

RRP – Redundant Route Processor

RS – router shelf

RS-232 – EIA/TIA-232

RSA – Rivest, Shamir, and Adelman (a public-key cryptographic system)

RSC – route switch controller

RSCPB – RSC front panel push button

RSCV – Route Selection Control Vector

rsh – remote shell

RSM – Route Switch Module

RSP – Route Switch Processor

RSPAN – Remote Switched Port Analyzer

RSRB – remote source-route bridging

RSRC – Resource

RSVP – Resource Reservation Protocol

RTAL – Receive Telecombus Aligner/Interface

RTC – real-time console

RTM – Real Time Monitor

RTP – Rapid Transport Protocol

RTP – Real-Time Transport Protocol

RTR – response time reporter

RTS – Request To Send

RTT – round-trip time

RTTMON – Round Trip Time Monitor

RU – request/response unit

RUDP – Reliable User Data Protocol

Rx – Receive

RXP – Resonate Exchange Protocol

SA – security association

SA – Source-Active

SA – Service Assurance

SADB – security association database

SAF24 – SAR adapter FPGA OC24

SAFI – Subsequent Address Family Identifier

SAP – service access point

SAR – segmentation and reassembly

SBE – single-bit error

SCB – storage control blocks

SCB – System Control Board

SCC – Signaling Connection Control

SCCP – Signaling Connection Control Part

SCM – Service Connection Manager

SCP – Service Control Point

SCP – Switch-Module Configuration Protocol

SCP – System Control Protocol

SCR – sustained cell rate

SDCC – Serial Data Communication Channel

SDEE – Security Device Event Exchange

SDF – Signature Definition File

SDLC – Synchronous Data Link Control

SDLLC – Synchronous Data Logical Link Control

SDM – Security Device Manager

SDP – Session Description Protocol

SDP – Shelf Discovery Protocol

SDRAM – synchronous DRAM

SDT – Start Data Transfer

SEF – severely errored frames

SERDES – Serializer-Deserializer

SFC – switch fabric card

SFP – Small Form Factor Pluggable

SGBP – Stack Group Bidding Protocol

SGCP – Simple Gateway Control Protocol

SGSN – Serving GPRS Support Node

SID – Service ID

SIMM – single in-line memory module

SIP – Session Initiation Protocol

SLARP – Serial Line Address Resolution Protocol

SLB – Server Load Balancing

SLC – signaling link code

SLCI – Signaling Link Code Interface

SLIC – Subscriber Line Interface Circuit

SLIP – Serial Line Internet Protocol

SLU – secondary logical unit

SM – sparse mode

SM – state machine

SMbus – System Management Bus

SMDS – Switched Multimegabit Data Service

SME – Signature Micro Engine

SMRP – Simple Multicast Routing Protocol

SMTP – Simple Mail Transfer Protocol

SNA – Systems Network Architecture

SNASw – SNA Switching Services

SNMP – Simple Network Management Protocol

SNR – signal-to-noise ratio

SNRM – Set Normal Response

SO-DIMM – Small Outline Dual In-line Memory Modules

SOF – start-of-frame

SOP – Second-Generation Packet-over-SONET

SOP – standard operation procedure

SP – Switch Processor

SPA – Shared Port Adapter

SPAN – Switched Port Analyzer

SPD – Security Policy Database

SPE – service processing element

SPI – security parameter index

SPID – service profile identifier

SPM – source path message

SPMM – SIMM DSP Module

SRA – Seamless Rate Adaptation

SRA – source routing accelerator

SRAM – static RAM

SRC – Switch Redundancy Controller

SRCP – Simple Resource Coordination Protocol

SRDB – Source Route Relational Database

SRIC – Sculptor Input Controller

SRIF – Sculptor Interface

SROC – Sculptor Output Controller

SRP – Server Redundancy Protocol

SRP – Spatial Reuse Protocol

SRR – Single Ring Recovery Protocol

SSA – Serial Storage Architecture

SSCOP – Service-Specific Connection-Oriented Protocol

SSCP – system services control points

SSE – silicon switching engine

SSG – Service Selection Gateway

SSH – Secure Shell

SSL – Secure Socket Layer

SSM – Single State Mode

SSM – Source Specific Multicast

SSO – single sign-on

SSO – Stateful SwitchOver

SSP – Silicon Switch Processor

SSP – state synchronization protocol

SSRAM – synchronous static RAM

SSRP – Simple Server Redundancy Protocol

SSS – Subscriber Service Switching

SSTP – Shared Spanning-Tree Protocol

STP – Spanning-Tree Protocol

STUN – serial tunnel

SU – service unit

SU – signaling unit

SVC – switched virtual circuit

SVI – switched virtual interface

SVIP – Versatile Interface Processor 2

SW56 – switched 56K

SWIDB – software for interface descriptor block

SYSMGT – system management

TAC – Cisco Technical Assistance Center

TACACS – Terminal Access Controller Access Control System

TBB – to backplane buffer

TBI – Ten Bit Interface

TBM – Transmit Buffer Manager

TCA – telecommunications access method

TCATM – Tag Control ATM

TCAM – Ternary Content Addressable Memory

TCB – Transmission Control Block

TCL – Toolkit Command Language

TCP – Transmission Control Protocol

TDM – time-division multiplexing

TDP – tag distribution protocol

TDR – time domain reflectometer

TE – terminal equipment

TE – tunnel equipment

TED – Tunnel Endpoint Discovery

TEI – terminal endpoint identifier

TFIB – Tag Forwarding Information Base

TFN – transfer number

TFTP – Trivial File Transfer Protocol

TG – transmission group

TIB – Tag Information Base

TIM – Tree Information Base

TIC – Toaster Input Controller

TID – Terminal Identifier

TIFF – tagged image file format

TLB – translation look-aside buffer

TLV – type, length, value

TMQ – terminal port queueing

ToS – Type of Service

TP – Transport Protocol

TR – Token Ring

TRANGE – time-range

TSC – Tag Switch Controller

TSCAM – Traffic Shaping Carrier Access Module

TSI – transmitting subscriber information

TSP – tag-switched path

TT2RP – Toaster-to-RP

TTAL – Transmit Telecombus Aligner/Interface

TTL – time to live

TVC – tag switched controlled virtual circuit

TVC – tag virtual circuits

Tx – transmit

UA – unnumbered acknowledgement

UART – Universal Asynchronous Receiver/Transmitter

UC – Unified Communications

UCCE – Unified Contact Center Enterprise

Ucode – Microcode

UDF – Undefined

UDLD – UniDirectional Link Detection

UDP – User Datagram Protocol

UPS – uninterruptible power supply

URM – Universal Router Module

uRPF – Unicast Reverse Path Forwarding

VACL – VLAN Access Control List

VAD – voice activity detection

VBR – variable bit rate

VBR-nRT – variable bit rate—non-real time

VC – virtual circuit

VCC – virtual channel connection

VCD – virtual circuit descriptor

VCCI – Virtual Channel Common Index

VCHAN – virtual channel

VCI – virtual channel identifier [ ATM only]

VCN – virtual circuit number

VDSL – very high bitrate digital subscriber line

VFC – voice feature card

VFC – VoIP feature card

VFR – Virtual Fragment Reassembly

VG – voice gateway

VIC – voice interface card

VIP – Versatile Interface Processor

VLAN – virtual LAN

VMAC – Virtual MAC

VMPS – VLAN Membership Policy Server

VMR – value, mask, result

VNM – Voice Network Manager

VoIP – Voice over IP

VP – virtual path

VPC – virtual path connection

VPD – voice packet driver

VPDN – Virtual Private Dial-up Network

VPI – virtual path identifier

VPN – Virtual Private Network

VPNv4 – Virtual Private Network Version 4

VQP – VLAN Query Protocol

VQPC – VQP Client

VRF – VPN Routing and Forwarding

VRRP – Virtual Router Redundancy Protocol

VSI – Virtual Switch Interface

VSM – Voice Service Manager

VT – virtual terminal

VTAM – virtual telecommunications access method

VTMS – Versatile Traffic Management and Shaping

VTP – VLAN Trunk Protocol

VTSP – voice telephony service provider

VTT – voltage termination

VWIC – Voice/WAN interface card

WCCP – Web Cache Communication Protocol

WCS – writable control store

WDS – Wireless Domain Services

WIC – WAN Interface Card

WLM – Workload Manager

WRED – Weighted Random Early Detection

WWW – World Wide Web

XCA – external communication adapter

XCVR – transceiver

XDR – eXternal Data Representation

XID – exchange identification

XML – eXtensible Markup Language

XNS – Xerox Network Systems

XOT – X.25-over-TCP

XTagATM – extended tag ATM

ZBT – zero bus turnaround