Acronym guide
This Acronyms Guide is a handy guide to help you decipher the telecom industry's acronym alphabet soup.
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| Numerics | ||
|---|---|---|
| Name | Position | |
| Numerics | ||
| 2F | Two-Fiber | |
| 3G | 3rd Generation | |
| 4C | Consortium of Intel, IBM, Matsushita, and Toshiba | |
| 4F | Four-Fiber | |
| 5C | Consortium of Intel, Sony, Matsushita, Toshiba, and Hitachi | |
| 10 GbE | 10 Gigabit Ethernet | |
| 10 GFC | 10 Gigabit Fibre Channel (Same as FC1200) | |
| A | ||
| A-TDMA | Advanced Time Division Multiple Access | |
| A/D | Analog-to-Digital | |
| AAL | ATM Adaptation Layer | |
| AAL0 | ATM Adaptation Layer Type 0 | |
| AAL1 | ATM Adaptation Layer Type 1 | |
| AAL2 | ATM Adaptation Layer 2 Transport | |
| AAL3/4 | ATM Adaptation Layer Type 3 and 4 | |
| AAL5 | ATM Adaptation Layer 5 | |
| ABR | Available Bit Rate | |
| ABT | Advanced BiCMOS Technology | |
| AC | Alternating Current; Administrative Complex; Atomic Clock | |
| AC-3 | Audio Coding Revision 3 | |
| ACAC | Actual Call Admission Control | |
| ACEG | Alternating Current Equipment Ground | |
| ACK | Acknowledge | |
| ACL | Active Control List; Access Control List | |
| ACO | Alarm Cutoff | |
| ACQ | Acquire | |
| ACR | Allowed Cell Rate | |
| ACS | Automatic Channel Shutdown; Alarm Correlation and Suppression | |
| ACSE | Association Control Service Element | |
| ACSS | Automatic Channel Shutdown Suppression; Automatic Channel Shutdown State | |
| ACT | Active | |
| ADC | Analog-to-Digital Converter; Add/Drop Coupler | |
| ADI | Asset Distribution Interface | |
| ADM | Add/Drop Multiplexer | |
| ADP | Actual Departure Potential | |
| ADSL | Asymmetric Digital Subscriber Line | |
| ADT | Actual Departure Time | |
| AE | Automation Engine | |
| AES | Advanced Encryption Standard | |
| AESA | ATM End System Address | |
| AFI | Authority and Format Identifier | |
| AFM | APS Mode Mismatch Failure | |
| AGC | Automatic Gain Control | |
| AGGR | Aggregate | |
| AID | Access Identifier | |
| AIM | Auto Image Management; Active Inventory Map | |
| AINI | ATM Inter-Network Interface | |
| AINS | Automatic in Service State | |
| AIR | Additive Increase Rate | |
| AIS | Alarm Indication Signal | |
| AIS-L | Alarm Indication Signal - Line | |
| AIS-P | Alarm Indication Signal - Path | |
| AIS-S | Alarm Indication Signal - Section | |
| AIS-V | VT Alarm Indication Signal | |
| AISDP | Alarm Indication Signal Decay Period | |
| AISIP | Alarm Indication Signal Integration Period | |
| ALMLED2U | Alarm LED 2 RU (Online Edge Platform) | |
| ALS | Automatic Laser Shutdown | |
| AM | Amplitude Modulation; Application Manager | |
| AMF | APS Mode Mismatch Failure | |
| AMI | Access Method Interface; Alternate Mark Inversion | |
| AMM | Alarm Management Module; Auxiliary Management Module | |
| AMP | Amplifier | |
| AMS | Asset Management System | |
| ANSI | American National Standards Institute | |
| AO | Autonomous Output | |
| AOD | Advertising on Demand | |
| APC | Angled Physical Contact | |
| APD | Avalanche PhotoDiode | |
| API | Application Program Interface | |
| APS | Automatic Protection Switching | |
| APSBF | Automatic Protection Switching Byte Failure | |
| APSCM | Automatic Protection Switching Channel Mismatch | |
| APSMM | Automatic Protection Switching Mode Mismatch | |
| ARC | Alarm Reporting Control | |
| ARP | Address Resolution Protocol | |
| ARPU | Average Revenue per Unit (or User) | |
| AS | Autonomous System | |
| ASAP | Alarm Severity Assignment Profile | |
| ASCII | American Standard Code for Information Interchange | |
| ASD | Access Security Device | |
| ASE | Amplified Spontaneous Emission | |
| ASI | Asynchronous Serial Interface | |
| AsiaPac | Asia Pacific | |
| ASIC | Application-Specific Integrated Circuit | |
| ASN.1 | Abstract Syntax Notation One | |
| ASP | Applications Service Provider; Average Selling Price | |
| ASYNC | Asynchronous | |
| AT | Advanced Technology | |
| AT&T | American Telephone and Telegraph 91ÌÒÉ« | |
| ATA | Advanced Technology Attachment | |
| ATAF | ATM Test Access Function | |
| ATAG | Autonomous Tag | |
| ATAGSEQ | Autonomous Tag Sequence | |
| ATDMA | Asynchronous Time Division Multiple Access | |
| ATM | Asynchronous Transfer Mode | |
| ATM SAM | ATM Service Access Multiplexer | |
| ATMVCL | ATM Virtual Channel Link | |
| ATMVPL | ATM Virtual Path Link | |
| ATTN | Attenuator | |
| AU/AU-x | Administrative Unit | |
| AU-n | Administrative Unit "n" | |
| AUG | Administrative Unit Group | |
| AUX | Auxiliary | |
| AVC | Attribute Value Change | |
| AWG | American Wire Gauge | |
| AWGN | Additive White Gaussian Noise | |
| B | ||
| B-DCS | Broadband Digital Cross-connect System | |
| B-PON | Broadband Passive Optical Network | |
| B-RAS | Broadband Remote Access Server | |
| B/P | Backplane | |
| B3ZS | Bipolar With 3-Zero Substitution | |
| B6ZS | Bipolar With 6-Zero Substitution | |
| B8ZS | Bipolar With 8-Zero Substitution | |
| BA | Booster Amplifier | |
| BB | Broadband | |
| BBE | Background Block Error | |
| BBE-RS | Background Block Error Regenerator Section (an SDH regenerator section error) | |
| BBER | Background Block Error Ratio | |
| BC | Business Continuity | |
| BCD | Binary-Coded Decimal | |
| BCST | Broadcast | |
| BDFB | Battery Distribution Fuse Bay | |
| BE | Block Error; Best Effort | |
| BE-RS | Block Errors-Regenerative Section | |
| BECN | Backward Explicit Congestion Notification | |
| BELLCORE | BELL Communications Research, Inc. | |
| BER | Bit Error Rate | |
| BER-SD-P | Path Signal Degrade BER | |
| BER-SF-P | Path Signal Failure BER | |
| BERT | Bit Error Rate Test | |
| BFP | Back Facet Power | |
| BGP | Border Gateway Protocol | |
| BGP4 | Border Gateway Protocol, version 4 | |
| BICI | Broadband Inter-Carrier Interfaces; B-ISDN Inter-carrier Interface | |
| BICSI | Building Industry Consulting Services International | |
| BIOS | Basic Input/Output System | |
| BIP | Bit Interleaved Parity | |
| BIT | Built-In Test | |
| BITS | Building Integrated Timing System | |
| bits/sym | Bits per Symbol | |
| BLSR | Bidirectional Line Switched Ring | |
| BML | Business Management Layer | |
| BNC | Bayonet Neill-Concelman | |
| BOC | Bell Operating 91ÌÒÉ« | |
| BOL | Beginning of Life | |
| BOM | Bill of Materials | |
| BONDING | Bandwidth ON Demand Interoperability Group | |
| BOOTP | Bootstrap Protocol | |
| BP | Backplane | |
| BPI | Baseline Privacy Interface | |
| BPI+ | Baseline Privacy Interface Plus | |
| BPP | Backplane Protocol | |
| bps | bits per second | |
| BPSR | Bidirectional Path Switched Ring | |
| BPT | Band Pass-Through | |
| BPV | BiPolar Violations | |
| BRI | Basic Rate Interface | |
| BRM | Backward RM | |
| BSC | Board SC Connector | |
| BSP | Board Support Package | |
| BSS | Business Support System | |
| BT | British Telecom; Burst Tolerance | |
| Btag | Beginning Tag | |
| BTM | Bits Termination Circuit Pack | |
| BTS | Business Telecom Services | |
| BTU/hr | British Thermal Unit per hour | |
| BW | Bandwidth | |
| BWDM | Band Wavelength Division Multiplexer | |
| BYT | Total Byte Count | |
| C | ||
| C | Celsius; Critical | |
| C2O | Cable to Optic | |
| CA | Content Archived | |
| CAB | Conformity Assessment Body | |
| CAC | Connection Admission Control; Call Admission Control | |
| CAD | Computer Aided Design | |
| CALA | Central America and Latin America | |
| CAM | Content Addressable Memory | |
| CAPEX | Capital Expenditure | |
| CAS | Channel Associated Signaling | |
| CATV | Community Antenna Television; Cable Television | |
| CB, C/B | Circuit Breaker | |
| C-BAE | C-Band Amplifier Equalizer | |
| C-BAM | C-Band Amplifier Monitor | |
| CBN | Common Bonding Network | |
| CBR | Constant Bit Rate | |
| CC | Cross Connection; Clear Channel | |
| CCB | Configuration Control Board | |
| CCC | Cross Connect Controller | |
| CCCG | Cross Connection and Control Group | |
| CCC-PC | CCC Processor Card | |
| CCDF | Complementary Cumulative Distribution Function | |
| CCI | Content Control Information | |
| CCITT | Consultative Committee on International Telegraphy and Telephony | |
| CCK | Complimentary Code Keying | |
| CCW | Counterclockwise | |
| CCC-XC | CCC Cross Connect Card | |
| CCC768 | Cross Connect Fabric with 768x768 STS-1 capacity | |
| CD | Compact Disc; CoreDirector®; Chromatic Dispersion | |
| CDD | CoreDirector® Designer Software Tool | |
| CDE | Common Desktop Environment (UNIX) | |
| CDR | Call Detail Recording; Clock and Data Recovery | |
| CD-ROM | Compact Disc Read Only Memory | |
| CDE | Common Desktop Environment | |
| CDMA | Code Division Multiple Access | |
| CDP | Contracted Deadline Potential | |
| CDT | Connection Dropping Threshold | |
| CDTS | Chromatic Dispersion Test Set | |
| CDV | Cell Delay Variation | |
| CDVT | Cell Delay Variation Tolerance | |
| CD-WO | Compact Disc - Write One | |
| CE | Consumer Electronics | |
| CEA | Consumer Electronics Association | |
| CER | Cell Error Ratio; Codeword Error Ration | |
| CES | Circuit Emulation Service | |
| CEV | Controlled Environmental Vault | |
| CFG | Configuration | |
| CFM | Cubic Feet per Minute | |
| CFU | Cooling Fan Unit | |
| CH | Channel | |
| CHASEH | Environmentally Hardened Chassis | |
| CHASSIS-e | Old Chassis Type | |
| CHASYNC | Chassis with Sync | |
| C/I | Carrier-to-Interface Ratio | |
| CI | Compact Intelligence; Craft Interface; Customer Interface; Certified Integrator | |
| CID | Circuit Identification; Craft Interface Device | |
| CIF | Client Interface | |
| CIFS | Common Internet File System | |
| CIM | Client Interface Module | |
| CINOT | Ciena Optical Transport System | |
| CIR | Customer Information Release | |
| CIT | Craft Interface Terminal; Craft Interface Tool | |
| CL | Coupling Loss; Cleared | |
| CLEC | Competitive Local Exchange Carrier | |
| CLEI | Common Language Equipment Identifier | |
| CLEITM | Common Language Equipment Identifier | |
| CLFI | Common Language Facility Identifier | |
| CLI | Command Line Interface | |
| CLIP | Calling Line Identification Presentation | |
| CLIR | Calling Line Identification Restriction | |
| CLLI | Common Language Location Identifier | |
| CLNP | Connectionless Network Layer Protocol | |
| CLNS | Connectionless Network Service | |
| CLP | Cell Loss Priority | |
| CLR | Cell Loss Ratio | |
| CLTP | Connectionless Transport Protocol | |
| cm | centimeter | |
| CM | Control Module; Cable Modem | |
| CM-CLI | Control Module Command Line Interface | |
| CMF | Channel Mismatch Failure; Client Management Frame | |
| CMIP | Common Management Information Protocol | |
| CMIS | Common Management Information Services | |
| CMISE | Common Management Information Service Element | |
| CMO | Ciena Management Object | |
| CMR | Cell Misinsertion Rate | |
| CMS | Call Management Server | |
| CMTS | Cable Modem Termination System | |
| CMU | Clock Multiplier Unit | |
| C-n | Container C-11=1,544 Mb/s; C-12=2,048 Mb/s; C-2=6,312 Mb/s; C-3=34,368 Mb/s and 44,736 Mb/s; C-4=139,264 Mb/s | |
| CNIPS | Core Network Integrated Planning System | |
| CNIR | Carrier-to-Noise/Ingress Ratio | |
| CNMP | Customer Network Management Portal | |
| CNR | Carrier-to-Noise Ration | |
| CO | Central Office | |
| COADM | Configurable Optical Add/Drop Multiplexer | |
| COBRA | Copper and Optical Broadband Remote Access | |
| CODEC | Coder/Decoder | |
| COE | Central Office Equipment | |
| COFA | Change of Frame Alignment | |
| COM | Ciena's inter-processor communications system | |
| COLD | Central Office Layout Design | |
| COLL | Collision Count | |
| CONDTYPE | Condition Type | |
| CONS | Connection Oriented Network Service | |
| COPS | Common Open Policy Services | |
| CORBA | Common Object Request Broker Architecture | |
| CoS Class of Service | ||
| COS | Class of Service; Common Object Services | |
| COT | Central Office Terminal | |
| COTS | Commercial off the Shelf | |
| CP | Circuit Pack; Control Processor; Connection Provisioner; Call Processing; Customer Premise | |
| CPCI | Compact Peripheral Component Interconnect | |
| CPD | Common Path Distortion | |
| CPE | Customer Premises Equipment; Customer Provided Equipment | |
| C-Plane | Control Plane | |
| CPLD | Complex Programmable Logic Device | |
| CPM | Cross-Phase Modulation | |
| CPRM | Content Protection for Recordable Media | |
| CPT | Channel Pass-Through | |
| CPTTAG | Connection Termination Point Tag | |
| CPU | Central Processing Unit | |
| CR | Circuit Reliability; Carriage Return; Critical Alarm | |
| CRC | Cyclic Redundancy Check | |
| CRG | Circuit Restoration Group | |
| CRIP | CIENA Routing Information Protocol | |
| CR-LDP | Constraint-based Routing Label Distribution Protocol | |
| CRS | Cross Connect | |
| CRT | Cathode Ray Tube | |
| CRx Line | Client Receive Line | |
| CS | Control Sub-span; Convergence Sublayer; CoreStream | |
| CSA | Canadian Standards Association | |
| CSD | Core Switching Division | |
| CSES | Consecutive Severely Errored Seconds | |
| Csh | C Shell | |
| CSH | Common Signal Header | |
| CSI | Convergence Sublayer Indicator | |
| CSM | Core Switching Manager | |
| C-SMF | Conventional Single Mode Fiber | |
| CSO | Composite Second Order | |
| CSP | Customer Service Profile | |
| CSR | Customer Service Representative | |
| CS-RZ | Carrier-Suppressed Return-to-Zero | |
| CST | Central Standard Time | |
| CSU | Channel Service Unit; Customer Service Unit | |
| CSV | Comma-Separated Value | |
| CT | Critical | |
| Ctag | Correlation Tag | |
| CTAM | Cable & Telecommunications Association for Marketing | |
| CTB | Composite Triple Beat | |
| CTC | Common Transmit Clock | |
| CTD | Cell Transfer Delay | |
| CTG | Cradle-To-Grave | |
| CTM | Core Transport Manager | |
| CTN | Core Transmission Network | |
| CTP | Connection Termination Point | |
| CTS | Clear To Send | |
| CTx Line | Client Transmit Line | |
| CUG | Closed User Group | |
| CV | Code Violation | |
| CV-FE | Code violation - Far End | |
| CV-L | Code Violation - Line | |
| CV-P | Code Violation - Path | |
| CV-PFE | Code Violation - Path Far End | |
| CV-S, CVS | Code Violation - Section; Code Violation -- Seconds | |
| CW | Clockwise; Continuous Wave | |
| CWDM | Coarse Wave Division Multiplexing; Coarse Wavelength Division Multiplex | |
| CWDM-U | Coarse Wavelength Division Multiplexing - UPSR | |
| D | ||
| D/A | Digital-to-Analog | |
| DAC | Digital to Analog Converter; Digital Addressable Controller | |
| DACS | Digital Access and Cross-Connect System | |
| DAD | Direct Access Devise | |
| DADM | Data Add/Drop Multiplexer | |
| DAS | Direct Attached Storage | |
| dB | decibel | |
| DB | Database | |
| DBA | Dynamic Bandwidth Assignment | |
| dBc | Decibel referenced to the carrier | |
| dBm | Decibel reference in milliwatts | |
| DBMS | Database Management System | |
| DBPSK | Differential Binary Phase Shift Keying | |
| DBS | Direct Broadcast Satellite | |
| DB-9 | Data Bus 9 Pin Connector | |
| DC | Direct Current; Data Connection | |
| D&C | Drop and Continue | |
| DCC | Data Communications Channel | |
| DCE | Data Communications Equipment; Data Circuit Terminating Equipment | |
| DCF | Dispersion-Compensating Fiber | |
| DCG | Dispersion Compensation Grating | |
| DCM | Dispersion Compensation Module | |
| DCN | Data Communication Network | |
| DCOM | Distributed Component Object Model | |
| DCP | Digital Communications Protocol; Device Control Protocol | |
| DCS | Digital Cross-connect System; Digital Connection System | |
| DDI | Direct Dialing Inward | |
| DDS | Digital Data Storage; Digital Data Service; Digital Data System; Digital Data Stream | |
| DE | Discard Eligible | |
| DEC | Digital Electrical Carrier | |
| DEG | Degraded Signal | |
| DEMUX | Demultiplexer | |
| DENI | Digital Entertainment Networking Initiative | |
| DENY | Transaction Denier | |
| DFB | Distributed Feedback | |
| DG | Disc Group | |
| DGD | Differential Group Delay | |
| DHCP | Dynamic Host Configuration Protocol | |
| DHWG | Digital Home Working Group | |
| D/I | Drop and Insert | |
| DIO | Digital Input/Output | |
| DIP | Dual In-line Package (switch) | |
| DIR | Direction | |
| DiffServ | Differentiated Services | |
| Div | Division | |
| DLC | Digital Loop Carrier | |
| DLCI | Data Link Connection Identifier | |
| DLL | Dynamic Link Library; Data Lind Layer (driver); Downline Load | |
| DLT | Digital Linear Tape Drives | |
| DM | Degraded Minute; Dispersion Mitigation | |
| DMA | Direct Memory Access | |
| DMACS | Distributed Monitoring and Control System | |
| DMB | Digital Multipoint Bridge; Document Maintenance Bulletin | |
| DMC | Dual Modem Cards | |
| DMH | Degraded Modem Hours | |
| DMM | Digital Multi-Meter | |
| DMOP | Detailed Method of Procedure | |
| DMS | Dispersion-managed Solution | |
| DMUX | [Optical] Demultiplexer | |
| DN | Data Node | |
| DNCS | Digital Network Control System | |
| DNR | Do Not Revert | |
| DNS | Domain Name Server; Domain Name System | |
| DOCSIS | Data-Over-Cable Service Interface Specifications | |
| DOS | Disk Operating System | |
| DoS | Denial of Service | |
| DPDT | Double-Pole, Double-Throw | |
| DPFI | Data Plane Fault Isolation | |
| DPI | Digital Program Insertion | |
| DPR | Dedicated Protection Ring | |
| DPRAM | Dual Port Random Access Memory | |
| DPT | Dynamic Packet Transport | |
| DQ | Degraded Quality Level | |
| DQDB | Distributed Queue Dual Bus | |
| DQoS | Dynamic Quality of Service; Deploying Quality of Service | |
| DQPSK | Differential Quadrature Phase Shift Keying | |
| DR | Disaster Recovery | |
| DRAM | Dynamic Random Access Memory | |
| DRM | Digital Rights Management | |
| DS | Digital Signal; Downstream | |
| DS0 | Digital Signal Level 0 (64 Kb/s data/voice channel) | |
| DS1 | Digital Signal Level 1 (T1 equivalent) | |
| DS3 | Digital Signal Level 3 (T3 equivalent) | |
| DSCP | Differentiated Service Code Point | |
| DSCRDS | Discard Count | |
| DSF | Dispersion Shifted Fiber | |
| DSL | Digital Subscriber Line; Digital Subscriber Loop | |
| DSLAM | Digital Subscriber Line Access Multiplexer | |
| DS-n | Digital Signal, level n | |
| DSP | Digital Signal Processor | |
| DSS2 | Digital Subscriber Signaling 2 | |
| DSTB | Digital Set-top Box | |
| DSX | Digital Side Interface | |
| DSX-1 | Digital Signal Level 1 Cross Connect | |
| DS-x | Digital Signal where N denotes multiple of 51.84 Mb/s | |
| DSX-3 | Digital Signal Level 3 Cross Connect | |
| DT | Decision Technology; Direct Termination | |
| DTCP | Digital Transmission Content Protection | |
| DTE | Data Terminal Equipment | |
| DTL | Designated Transit List | |
| DTMF | Dual Tone Multi-Frequency | |
| DTS | Dynamic Transport System | |
| DTV | Digital Television | |
| DUART | Dual Universal Asynchronous Receiver Transmitter | |
| DUP | Data User Part | |
| DUS | Don't Use Synchronization | |
| DV | Digital Video | |
| DVB-ASI | Digital Video Broadcast Asynchronous Serial Interface | |
| DVC | Dynamic Virtual Concatenation | |
| DVD | Digital Versatile Disc | |
| DVD+R | Recordable Digital Versatile Disc | |
| DVD+RW | Rewritable Digital Versatile Disc | |
| DVI | Display Visual Interface | |
| DVM | Digital Voltmeter | |
| DVOW | Digital Voice Orderwire | |
| DVR | Digital Video Recorder | |
| DW | Datawire | |
| DWDM | Dense Wavelength Division Multiplexing | |
| DXC | Digital Cross-Connect | |
| DXI | Data Exchange Interface | |
| E | ||
| E1 | European Equivalent of T1 (2.048 Mb/s signal speed) | |
| E2E | End To End | |
| E2PROM | Electrically Erasable Programmable Read Only Memory | |
| E3 | European data signal at a rate of 34.368 Mb/s | |
| EAL | Events, Alarms, and Logging | |
| EAI | Enterprise Application Integration | |
| EAP | Extensible Authentication Protocol | |
| EAS | Emergency Alert System | |
| EB | Error Block; Eastbound | |
| EBEM | Enhanced Bus Extender Module | |
| EC-1 | Electrical Carrier Level 1 (STS1 Equivalent) | |
| ECC | Edge Card Control; Embedded Communications Channel | |
| ECI | Equipment Catalog Item | |
| ECLR | Egress Cell Loss Ratio | |
| ECn | Electrical Carrier, level n; 0=64 kb/s, 2=6,312 Mb/s, 3=44,736 Mb/s | |
| ECN | Engineering Change Notice | |
| ECO | Engineering Change Order | |
| ED | Equipment Degrade | |
| EDF | Erbium-Doped Fiber | |
| EDFA | Erbium-Doped Fiber Amplifier | |
| eDOCSIS | Embedded Data-Over-Cable Service Interface Specifications | |
| EEE | Electronic Equipment Enclosure | |
| EEPROM | Electrically Erasable Programmable Read Only Memory | |
| EF&I | Engineer, Furnish and Install | |
| EF | Equipment Failure | |
| EFCI | Explicit Forward Congestion Indication | |
| EFD | Event Forwarding Discriminator | |
| EFEC | Enhanced Forward Error Correction | |
| EFP | Equipment Fault Protection | |
| EH | Environmentally Hardened | |
| EIA | Electronic Industries Alliance; Electronic Industries Association | |
| EID | Equipment Identifier | |
| EIDE | Enhanced Integrated Drive Electronics | |
| EIRP | Effective Isotropic Radiated Power | |
| EJB | Enterprise Java Beans | |
| ELAN | Emulated Local Area Network | |
| ELR | Extra Long Reach | |
| EM | Element Manager | |
| EMC | ElectroMagnetic Compatibility | |
| EMD | Extended Management Domain | |
| EMEA | Europe, Middle East and Africa | |
| EMBS | Egress Maximum Burst Size | |
| EMG | Extended Management Gateway | |
| EMI | Electromagnetic Interference | |
| EML | Element Management Layer; Electro-Absorptive Modulated Laser | |
| EMP | Expiring Maintenance Process | |
| EMS | Element Management System | |
| EMT | Expiring Maintenance Tool | |
| eMTA | Embedded Multimedia Terminal Adapter | |
| EMX | ESCON MUX | |
| END | Extended Management Domain | |
| ENE | End Network Element | |
| ENUT | Enhanced Non-preemptable Unprotected Traffic | |
| EO | Equipment Order | |
| EOC | Embedded Operations Channel | |
| EoD | Everything on Demand | |
| EOF | End of Frame | |
| EOL | End of Life | |
| EOM | End of Message | |
| EoS | Ethernet over SONET/SDH | |
| EOW | Engineered Orderwire; Express Orderwire | |
| E-PON | Ethernet Passive Optical Network | |
| EPA | Environmental Protection Agency | |
| EPCR | Egress Peak Cell Rate | |
| EPD | Early Packet Discard | |
| EPG | Equipment Protection Group | |
| EPL | Ethernet Private Line | |
| EPLD | Erasable Programmable Logic Device | |
| EPROM | Erasable Programmable Read Only Memory | |
| EQPT | Equipment | |
| ER | Extended Reach | |
| ERDI | Enhanced Remote Defect Indicator | |
| EREI-P | Enhanced Path Remote Error Indication | |
| Errcde | Error Code | |
| ES | Errored Second | |
| ESA | EDFA Saturation Algorithm; End System Address | |
| ESCBND | ESCON Bundle | |
| ESCON | Enterprise System Connection; IBM Enterprise systems connection protocol | |
| ESCR | Egress Sustainable Cell Rate | |
| ESD | Electrostatic Discharge | |
| ESDS | Electrostatic Discharge Sensitive | |
| ESF | Extended Super Frame; Extended Superframe Format | |
| ES-FE | Errored Seconds - Far End | |
| ESI | End System Identifier | |
| ES-IS | End System to Intermediate System | |
| ES-L | Errored Seconds - Line | |
| ES-LFE | Errored Second-Line Far End | |
| ES-MS | Errored Seconds at the Mulitplexor Section | |
| ESMOP | Electronic Service Method of Procedure | |
| ESN | Extended Subnetwork | |
| ES-P | Errored Seconds - Path | |
| ES-PFE | Errored Seconds - Path Far End | |
| ESR | Errored Second Ratio | |
| ES-RS | Errored Second Regenerator Section | |
| ES-S | Errored Seconds - Section | |
| EST | Eastern Standard Time | |
| ES-V | Errored Second-Virtual Tributary (VT) Path; Errored Second-VT Path Far End | |
| ESx | Errored Second Count | |
| ET | End Terminal; Entitlement Tracker | |
| Etag | Ending Tag | |
| ETH | 10/100 Ethernet | |
| ETHBND | Ethernet Bundle | |
| ETLMI | ESCON Trib Laser Manager Interface | |
| ETR | External Timing Reference | |
| ETSI | European Telecommunications Standards Institute | |
| EU | European Union | |
| EVM | Error Vector Magnitude | |
| EVPL | Ethernet Virtual Private Line | |
| EVPLAN | Ethernet Virtual Private Local Area Network | |
| EWO | Engineering Work Order | |
| EXER-R | Exercise - Ring | |
| EXER-S | Exercise - Span (SONET) | |
| EXP | Experimental | |
| EXZ | Excessive Zone | |
| F | ||
| F | Fahrenheit | |
| FA, F/A | Fuse Alarm; Fault Alarm | |
| FAB | Field Alert Bulletin | |
| FAD | Functional Access Domain | |
| FAF | Facility Failure | |
| F&I | Furnish and Install | |
| FC | Failure Code; Failure Count; Fiber Channel; Fibre Channel | |
| FC100 | Fibre Channel 1 Gb/s | |
| FC200 | Fibre Channel 2 Gb/s | |
| FC400 | Fibre Channel 4 Gb/s | |
| FC10000 | Fibre Channel 10 Gb/s (same as 10GFC) | |
| FCAPS | Fault, Configuration, Accounting, Performance (or Provisioning), Security management | |
| FCC | Federal Communications Commission | |
| FC-FE | Failure Count - Far End | |
| FCIP | Fiber Channel over Internet Protocol | |
| FC-L | Failure Count - Line | |
| FC-LFE | Failure Count - Line Far End | |
| FCM | Fan Control Module | |
| FCP | Fiber Channel Protocol | |
| FC-P | Failure Count - Path | |
| FC-PFE | Failure Count - Path Far End | |
| FCS | Frame Check Sequence | |
| FC Switch | Fiber Channel Switch | |
| FCS32 | Count of FCS-32 Error | |
| FC-V | Failure Count - VT | |
| FC-VFE | Failure Count - VT Far End | |
| FDA | Food and Drug Administration | |
| FDD | Frequency Division Duplexed | |
| FDDI | Fiber Distributed Data Interface | |
| FDF | Fiber Distributing Frame | |
| FDL | Facilities Data Link | |
| FDM | Frequency Division Multiplexing; Fast Ethernet | |
| FDMA | Frequency Division Multiple Access | |
| FDP | Fiber Distribution Panel | |
| FDRP | Frame Drop | |
| FE | Far End; Fast Ethernet; Forward Error Correction | |
| FEAC | Far End Alarm Channel | |
| FEACT | Far-End Terminal Alarm Condition | |
| FEALM | Far-End Alarm | |
| FEB | Fast Ethernet Bridging | |
| FEBE | Far End Block Error | |
| FEC | Forward Error Correction; Forwarding Equivalence Class | |
| FECN | Forward Explicit Congestion Notification | |
| FECS | Forward Error Correction Seconds | |
| FEDS | FICON Extended Storage over Distance | |
| FEP | Far End Protection | |
| FEPLF | Far End Protection Line Failure | |
| FEPM | Far End Performance Monitor | |
| FERF | Far End Receive Failure | |
| FET | Field-Effect Transistor | |
| FF | Fast Forward | |
| FFA | First Field Application | |
| FFP | Facility Fault Protection | |
| FFT | Fast Fourier Transform | |
| FIB | Forwarding Information Base | |
| FIC | Frame Identification Code | |
| FICON | Fiber Connection | |
| FIL | Fiber in the Loop | |
| FIT | Failure in Time | |
| FITB | Fiber in the Building | |
| FITL | Fiber in the Loop | |
| FITR | Fiber in the Riser | |
| FM | Fan Module; Fault Management; Forwarding Module; Frequency Modulation | |
| FMA | Failure Modes Analysis | |
| FMECA | Failure Mode and Effects and Criticality Analyses | |
| FMS | Fault Management System | |
| FO | Fiber Optics | |
| FOADM | Fixed Optical Add/Drop Multiplexer; Flexible Optical Add/Drop Multiplexer | |
| FOD | Free on Demand | |
| FOSC | Fiber Optic Splice Course | |
| FOTS | Fiber Optic Transmission System | |
| FP | Fabry-Perot (type of laser); Frame Pulse (NEC) | |
| FPG | Facility Protection Group | |
| FPGA | Field Programmable Gate Array | |
| FPM | Fan Power Module | |
| FPP | Fast Pattern Processor | |
| FPS | Frames per Second | |
| FR | Frame Relay | |
| FRC | Force | |
| FRD | Functional Requirements Document; Feature Requirements Definition | |
| FREQ | Frequency | |
| FRF | Frame Relay Forum | |
| FRF.12 | Frame Relay Forum Implementation Agreement 12 | |
| FRF.13 | Frame Relay Forum Implementation Agreement 13 | |
| FRF.5 | Frame Relay Forum Implementation Agreement 5 | |
| FRF.8.1 | Frame Relay Forum Implementation Agreement 8.1 | |
| FRG | Fragment Count | |
| FRM | Forward Resource Management; Frame Count | |
| FRMS | Dropped Frames | |
| FRU | Field Replacement Unit | |
| FS | File System | |
| FSA | Field Service Application | |
| FSAN | Full Services Access Network (consortium) | |
| FSB | Field Service Bulletin | |
| FSO | Free Space Optical | |
| FS-P | Forced Switch - Protection | |
| FS-R | Forced Switch - Ring | |
| FS-S | Forced Switch - Span | |
| FS-W | Forced Switch - Working | |
| FT-2000 | SONET OC-48 lightwave system (AT&T) | |
| FTA | Fault Tree Analysis | |
| FTAM | File Transfer and Access Management | |
| FTC | Fabric and Timing Card | |
| FTM | Fabric Timing Module | |
| FTP | File Transfer Protocol | |
| FTTB | Fiber to the Building; Fiber to the Business | |
| FTTC | Fiber to the Curb | |
| FTTD | Fiber to the Desk | |
| FTTH | Fiber to the Home | |
| FTTP | Fiber to the Premise; Maintenance Channel Transparent Termination Point | |
| FTTx | Fiber to the [endpoint] | |
| FUNI | Frame-based User-Network Interface | |
| FW | Firmware; Firewall | |
| FWHM | Full Width at Half Maximum | |
| FWM | Four-Wave Mixing | |
| G | ||
| GA | General Availability | |
| Gb | Gigabit | |
| GB | Gigabyte | |
| GbE | Gigabit Ethernet | |
| GbE VFTP | Gigabit Ethernet Virtual Facility Termination Point | |
| GbE WAN | Gigabit Ethernet Wide Area Network | |
| GbE WIF | Gigabit Ethernet Wide Area Network Interface | |
| GBIC | Gigabit Interface Converter | |
| Gbps, Gbits | Gigabits per second | |
| Gbytes/s | Gigabytes per second | |
| GC | Gateway Controller | |
| GCAC | Generic Connection Admission Control | |
| GCC0 | General Communications Channel 0 (similar to SDH/SONET DCC) | |
| GCIT | Graphical Craft Interface Terminal | |
| GCM | General Control Module | |
| GCRA | Generic Cell Rate Algorithm | |
| GDMO | Guidelines for the Definition of Managed Objects | |
| GE | Gigabit Ethernet; Greater than or equal to | |
| GEB | Gigabit Ethernet Bridge | |
| GET | Gigabit Ethernet Tunneling | |
| GFA | Gain Flattened Amplifier | |
| GFC | Generic Flow Control | |
| GFF | Gain Flattening Filter (used in EDFA) | |
| GFP | Generic Framing Procedure | |
| GFR | Guaranteed Frame Rate | |
| GHz | Gigahertz; One billion cycles per second | |
| GMPLS | Generalized Multi-Protocol Label Switching | |
| GMT | Greenwich Mean Time; Grasshoppers Made for Telecommunications (GMT fuses) | |
| GN | Gateway Network Element | |
| GNE | Gateway Network Element | |
| GND | Ground | |
| GOS | Grade of Service | |
| GP | Gateway Platform | |
| GPI | General Purpose Input | |
| GPIN | General Purpose Input | |
| GPO | General Purpose Output | |
| G-PON | Gigabit Passive Optical Network | |
| GPS | Global Positioning System; Global Positioning Satellite | |
| GR | Generic Requirement; Geographic Redundancy | |
| GRDM | Gigabit Rate Data Multiplexer | |
| GRTES | General Requirements for Transmission Equipment Specification | |
| GT | Gain Transfer; Grating Temperature | |
| GT | Gain Transfer; Grating Temperature | |
| GTP | Group Termination Point | |
| GUI | Graphical User Interface | |
| GW | Gateway | |
| GWC | Gateway Controller | |
| H | ||
| HA | High Availability | |
| HCFM | High-speed Cell Forwarding Module | |
| HCSFI | High-speed Central Switch Fabric Interface | |
| HD | High Definition | |
| HD-SDI | High Definition Serial Digital Interface | |
| HDB3 | High Density Bipolar 3 | |
| HDCP | High-bandwidth Digital Content Protection | |
| HDLC | High-speed/level Data Link Control | |
| HDMI | High Definition Multimedia Interface | |
| HDSF | High-speed Distributed Switch Fabric | |
| HDT | Host Digital Terminal | |
| HDTV | High Definition Television | |
| HE | Headend | |
| HEC | Header Error Control; Headend Controller | |
| HEM | Headend Modem | |
| HEPA | High Efficiency Particulate Arrester | |
| HFC | Hybrid Fiber Coax | |
| HFM | High-speed Forwarding Module | |
| HGW | Home Gateway | |
| HHP | Households Passed | |
| HISSA | High Speed Serial Application Specific Integrated Circuit (ASIC) | |
| HMS | Hybrid Management Sub-layer | |
| HNv1 | Home Networking Version 1 | |
| HO | Higher Order | |
| HOVC | Higher Order Virtual Concatenation | |
| HOD | HBO on Demand | |
| HOM | High-Order Modulation | |
| HomePNA | Home Phoneline Networking Alliance | |
| HO-DSP | High Order-Domain Specific Part | |
| HOP | High Order Path | |
| HO-POH | Higher Order - Path Overhead | |
| HO-DXC | Higher Order Digital Cross Connect | |
| HP | Hairpin; Higher Order Path; Homes Passed | |
| HPF | High Pass Filter | |
| HPFM | High-speed Packet Forwarding Module | |
| HPNA | Home Phoneline Networking Alliance | |
| HPOV | Hewlett Packard Open View | |
| HP-UX | Hewlett Packard's UNIX-based OS that runs on HP's enterprise servers | |
| HRD | Hardware Release Document; Hardware Requirements Document | |
| HS | High Speed | |
| HSB | High Speed Bus | |
| HSD | High Speed Data | |
| HI | Hardware/Software Interface; Hardware-Software Integration; High Speed Internet | |
| HSSI | High Speed Serial Interface | |
| HT | High Threshold | |
| HTML | Hyper Text Markup Language | |
| HTTP | Hypertext Transfer Protocol | |
| HVAC | Heating, Ventilation, and Air-Conditioning | |
| HW | Hardware | |
| Hz | Hertz | |
| I | ||
| I/O | Input/Output | |
| IAD | Integrated Access Device; Interface Access Device | |
| IAS | Internet Access Service; Internet Authentication Service | |
| IBCC | In-Band Communication Channel | |
| IC | Integrated Circuit | |
| ICB | Independent Customer Builds | |
| ICD | International Code Designator | |
| ICLR | Ingress Cell Loss Ratio | |
| ICMP | Internet Control Message Protocol | |
| ICNV | Input- Command Not Valid | |
| ICP | IMA Control Protocol | |
| ICPT | Installed Circuit Pack Type | |
| ICR | Initial Cell Rate | |
| ID | Identifier; Identification | |
| IDE | Integrated Device Electronics | |
| IDF | Intermediate Distribution Frame; Invalid Data Flag | |
| IDH | Identification High byte | |
| IDI | Initial Domain Identifier | |
| IDL | Interface Definition Language | |
| IDNV | Input- Data Not Valid | |
| IDP | Initial Domain Part | |
| IDS | Intrusion Detection System | |
| IDT | Inter-DXC Trunk | |
| IE | Information Element | |
| IEC | Incoming Error Count; InterExchange Carrier | |
| IEEE | Institute of Electrical and Electronics Engineers | |
| IETF | Internet Engineering Task Force | |
| IF | Intermediate Frequency | |
| IFC | Initial First Cost | |
| IG | Information Group | |
| IGMP | Internet Group Multicast Protocol | |
| IIAC | Input - Invalid Access Identifier | |
| IIOP | CORBA Internet Inter-ORB Protocol | |
| IISP | Interim Interface Signaling Protocol | |
| ILA | Intermediate Light Amplification; Integrated Line Amplifier; In-Line Amplifier | |
| ILEC | Incumbent Local Exchange Carrier | |
| ILM | Integrated Laser Module; Integrated Laser Modulator | |
| ILMI | Interim Link Management Interface; Interim Local Management Interface | |
| ILOG | Information Log; Incoming Log | |
| ILR | Issues List Report | |
| IM | Instant Messaging | |
| IMA | Inverse Multiplexing over ATM | |
| IMBS | Ingress Maximum Burst Size | |
| IMD | Intermodulation Distortion | |
| IME | Interface Management Entity | |
| IMT | Inter Machine Trunk | |
| IN | Intelligent Network | |
| I-NET | Institutional Network | |
| INM | Integrated Network Manager | |
| INMS | Integrated Network Management Suite; Integrated Network Management System | |
| INT | Internal; Internal Clock | |
| INTAP | Interoperability Technology Association for information Processing | |
| INTP | Internodal Tunneling Protocol | |
| INVW | Invalid Word Count | |
| IntServ | Integrated Services | |
| I/O | Input/Output | |
| IOA | Input/Output Adapter | |
| IOF | Inter-office Fiber | |
| IOR | Interoperable Object Reference | |
| IP | Internet Protocol | |
| IPC | Inter-process Communications; InterProcess or InterProcesser Control | |
| IPCR | Ingress Peak Cell Rate | |
| IPG | Inter-Packet Gap | |
| IPM | Interested Party Multicast | |
| IPMS | Interested Party Multicast Service | |
| IPPV | Impulse Pay per View | |
| IPOA | Internet Protocol over ATM | |
| IPsec | Internet Protocol Security | |
| IPTA | Internet Protocol Transport Agreement | |
| IPTV | IP Television | |
| IR | Intermediate Reach | |
| IRD | Integrated Receiver/Decoder | |
| IRT | Integrated Receiver/Transcoder | |
| IS | In Service; Intermediate System | |
| ISA | Industry Standard Architecture | |
| IS-ANR | In Service - Abnormal | |
| IS-ANRST | In Service - Abnormal and Restricted | |
| ISCC | InterSwitch Communications Channel | |
| ISCR | Ingress Sustainable Cell Rate | |
| iSCSI | Internet Small Computer System Interface; SCSI Protocol over TCP/IP | |
| ISD | Idle Signal Detection | |
| ISDN | Integrated Services Digital Network | |
| IS-IS | Intermediate System to Intermediate System | |
| ISM | Industrial Scientific Medical | |
| IS-NR | In Service - Normal | |
| ISO | International Standards Organization | |
| ISP | Internet Service Provider; Inside Plant | |
| IS-RST | In Service - Restricted | |
| ISTP | Internet Signaling Transport Protocol | |
| ISV | Independent Software Vendor | |
| IT | Information Technology | |
| ITA | Installation, Test, and Acceptance | |
| ITC | Independent Transmit Clock | |
| ITL | International Telecommunications Union | |
| ITE | Information Technology Equipment | |
| ITS | Intelligent Transportation System; Institute for Telecommunications Sciences | |
| ITT | International Telephone and Telegraph | |
| ITU | International Telecommunication Union | |
| ITU-T | International Telecommunications Union - Telecommunications Standards Section | |
| IUC | Interval Usage Code | |
| IWF | Interworking Function | |
| IXC | Inter-exchange Carrier | |
| J | ||
| J0 | J Zero; Section trace byte in performance monitoring (J-zero) | |
| J2EE | Java 2 Enterprise Edition | |
| JBR | Jabber Count | |
| JDBC | Java Database Connectivity | |
| JDK | Java Development Kit | |
| JDMK | Java Dynamic Management Kit | |
| JEM | JAVAâ„¢ Element Manager | |
| JMS | JAVAâ„¢ Messaging System | |
| JNDI | Java Naming and Directory Interface | |
| JRE | Java Runtime Environment | |
| JTAG | Joint Test Action Group | |
| JVM | Java Virtual Machine | |
| K | ||
| K1 | SONET or SDH overhead byte of VLSR or MSP/MS-SPRing (see K2) | |
| K2 | Used with K1-SONET or SDH overhead byte for VLSR or MSP/MS-SPRing | |
| Kb | Kilobit | |
| KB | Kilobyte | |
| Kb/s | Kilobits per second | |
| KB/s | Kilobytes per second | |
| Kbit/s | Kilobits per second | |
| Kbps | Kilobits per second | |
| KBps | Kilobytes per second | |
| kHz | KiloHertz | |
| Km | Kilometer | |
| Ksh | Korn Shell | |
| ksym/s | Kilosymbols per Second | |
| ksym/sec | Kilosymbols per Second | |
| kVA | 1000 Volt Amperes | |
| kW | Kilowatt | |
| L | ||
| L | Current | |
| L2TP | Layer 2 Tunneling Protocol | |
| L3 | Layer 3 | |
| LA | Line Adapter | |
| LAC | Local Access Concentrator | |
| LADM | Linear Add/Drop Multiplexer | |
| LAN | Local Area Network | |
| LANE | Local Area Network Emulation | |
| LAP | Link Access Procedure; Link Access Protocol | |
| LAPB | Link Access Procedure Balanced | |
| LAPD | Link Access Procedure-D Channel (X 25) | |
| LAPF | Link Access Procedure for Frame-Mode Bearer Services | |
| LAPS | Link Access Procedure | |
| LASER | Light Amplification by Stimulated Emission of Radiation | |
| LATA | Local Access and Transport Area | |
| LBC | Laser Bias Current | |
| LBCL | Laser Bias Current Level | |
| LBCN | Normalized Laser Bias Current | |
| LBO | Line Build Out | |
| LC | Lucent Connector; Line Card | |
| LCAP | Local Craft Access Panel | |
| LCAS | Link Capacity Adjustment Scheme | |
| LCC | Life-Cycle cost; Link Control Channel | |
| LCD | Liquid Crystal Display | |
| LCL | Lower Confidence Limit | |
| LCN | Local Computer Network; Logical Channel Number; Local Communications Network | |
| LCR | Least Cost Routing | |
| LCT | Large Capacity Terminal | |
| LD | Laser Diode | |
| LDAP | Lightweight Directory Access Protocol | |
| LDCC | Line Data Communications Channel | |
| LDP | Label Distribution Protocol | |
| LDS | Local Digital Switch | |
| LEAF | Large Effective Area Fiber | |
| LEC | Local Exchange Carrier | |
| LECS | LAN Emulation Configuration Server | |
| LED | Light Emitting Diode | |
| LER | Label Edge Router | |
| LES | LAN Emulation Server | |
| LF | Line Fail | |
| LFE | Line Far End | |
| LGN | Logical Group Node | |
| LGX | Light-Guide Crossconnects | |
| LH | Logical Host | |
| LIC | Line Interface Card | |
| LIF | Line Interface | |
| LIM | Line Interface Module | |
| LIP | Local Information Packet | |
| LIU | Line Interface Unit | |
| LLC | Logical Link Control | |
| LLSDCC | Lower-Layer Section DCC | |
| LM | Line Module | |
| LMI | Local Management Interface | |
| LMP | Link Management Protocol | |
| LO | Low Order | |
| LOADM | Lightweight Optical Add/Drop Multiplexer | |
| LOC | Loss of Clock | |
| Locn | Location | |
| LOF | Loss of Frame | |
| LOF-P | Path Loss of Frame | |
| LOH | Line Overhead | |
| LOM | Loss of Multiframe; List of Materials | |
| LOP | Loss of Pointer | |
| LOPDP | Loss of Pointer Decay Period | |
| LOPI | Loss of Pointer Inhibit | |
| LOPIP | Loss of Pointer Integration Period | |
| LOP-P | Loss of Pointer - Path | |
| LOP-V | VT Loss of Pointer | |
| LOS | Loss of Signal | |
| LOSS | Loss of Signal Seconds | |
| LOVC | Low-Order VC | |
| LOW | Local Orderwire | |
| LO-DXC | Low Order Digital Cross Connect | |
| LP | Line Processor; Lockout of Protection; Low Order Path | |
| LP-S/SF-P | Lockout of Protection - Span/Signal Fail - Protection | |
| Lport | Logical port | |
| LP-S | Lockout of Protection - Span | |
| LR | Long Reach (fiber); Line Regeneration Equipment | |
| LRDC | Long Reach Daughter Card | |
| LSA | Low Speed ADM | |
| LSA-E-EH | Low Speed ADM Electrical (10/100 Base-T) Environmentally Hardened | |
| LSA-O-EH | Low Speed ADM Optical (100 Base-FX) Environmentally Hardened | |
| LSB | Least Significant Bit | |
| LSF | Loss of Signal or Frame indication signal | |
| LSL | Lower Specification Limit | |
| LSM | Loss of Sync Message | |
| LSN | Logical Subnetwork | |
| LSP | Label Switched Path; Local Service Provider | |
| LSR | Label Switch Router | |
| LSSGR | LATA Switching System Generic Requirements | |
| LT | Low Threshold; Laser Temperature | |
| LTE | Line Terminating Equipment | |
| LTN | Local Transport Network (fiber ring) | |
| LTP | Link Termination Point; Logical Termination Point | |
| LTS | Loop Testing System; Long Term Storage | |
| LU | Line Unit | |
| LVD | Low-Voltage Distribution | |
| LWP | Low Water Peak | |
| LZS | Lempel Ziv Stac | |
| M | ||
| M12 | MUX DS-1 into DS2 | |
| M13 | MUX DS-1 into DS3 | |
| M23 | MUX DS-2 into DS3 | |
| MAC | Media Access Control; Medium Access Control | |
| MAN | Metropolitan Area Network | |
| MAP | Main Audio Program | |
| MAU | Media Access Unit | |
| Mb | Megabit | |
| MB | Megabyte | |
| Mbaud | Megabaud | |
| Mb/s | Megabits per second | |
| Mbits/s | Megabits per second | |
| Mbps | Megabits per second | |
| MBps | Megabytes per second | |
| MB/s | Megabytes per second | |
| MBS | Maximum Burst Size | |
| MCP | Management Control Processor | |
| MCT | Maintenance Channel Transparency | |
| MCTF | Motion Compensated Temporal Filtering | |
| MD | MetroDirector K2 Platform | |
| mDVR | Multi-TV Digital Video Recorder | |
| MCR | Minimum Cell Rate; Minimum Cost Routing | |
| MDF | Main Distribution Frame | |
| MDU | Multiple Dwelling Unit | |
| MEA | Mismatch of Equipment and Attributes | |
| MEGACO | Media Gateway Control Protocol | |
| MER | Modulation Error Ratio | |
| MFR | Multilink Frame Relay | |
| MG | Media Gateway | |
| MGC | Media Gateway Controller | |
| MGCP | Media Gateway Control Protocol | |
| MGN | Management Gateway Node | |
| MHz | Megahertz | |
| MIB | Management Information Base | |
| MID | Message Identifier | |
| MIPS | Millions of Instructions per Second | |
| MIT | Management Information Tree | |
| MJ | Major | |
| ML | Mediation Layer | |
| MLMD | Multiplexer/Demultiplexer | |
| MLPPP | Multi-Link Point-to-Point Protocol | |
| mm | millimeter | |
| MM | Multimode; Multimedia | |
| MME | Multiwave Management Element | |
| MMF | Multi-Mode Fiber | |
| MML | Man Machine Language | |
| MMO | Main Material Order | |
| MMP | Multiwave Management Element | |
| MN | Minor | |
| MO | Managed Object | |
| MOD | Module; Movies on Demand | |
| MODEM | Modulator-Demodulator | |
| MOF | Managed Object Framework | |
| MOP | Method of Procedure | |
| MOR | Multi-wavelength Optical Repeater | |
| MOS | Mean Opinion Score | |
| MP3 | MPEG-2 Layer 3 | |
| MP | Management Portal | |
| MPCKTS | Multicast Packet Count | |
| MPEG | Moving Pictures Expert Group | |
| MPI | Multi-Path Interface; Multi-Path Interference | |
| MPLmS | Multi-Protocol Lambda Switching | |
| MPLS | Multi Protocol Label Switching | |
| MPLS-CP | MPLS Control Plane | |
| MPN | Mode Partition Noise | |
| MPS | Modeling and Planning Suite | |
| MPOA | Multi Protocol over Asynchronous Transfer Mode | |
| MPS | Modeling and Planning System; Modeling and Planning Suite | |
| MPT | Multiplex Pass-Through | |
| MPTS | Multiple Program Transport Stream | |
| M-Plane | Management Plane | |
| MR | Modification Request; Material Request; Medium Reach | |
| MRRB | Maintenance Requirements Review Board; Material Release Review Board | |
| ms | Milliseconds | |
| MS | Multiplex Section | |
| MS-AIS | Multiplex Section - Alarm Indication Signal | |
| MSA | Mediation Services Administrator | |
| MSB | Most Significant Bit | |
| MSC | Metro Shelf Controller; Microsoft Cluster Server | |
| MSF | Multiservice Switching Forum | |
| MSM | Metro Switching Manager; Metro Switching Mismatch | |
| MSN | Multi-Subnetwork | |
| MSNM | Metro Switching Network Manager | |
| MSNM ML | Metro Switching Network Manager Mediation Layer | |
| MSO | Multiple System Operator | |
| MSOH | Multiplexer Section Overhead | |
| MSP | Multiplex Section Protection; Multiservice Switching Path | |
| MSPP | Multiservice Provisioning Platform | |
| MS-P | Manual Switch - Protection | |
| MSPVC | Management Soft Permanent Virtual Circuit | |
| MS-R | Manual Switch - Ring | |
| MS-RDI | Multiplex Section - Remote Defect Indication | |
| MS-REI | Multiplex Section Remote Error Indication | |
| MS-S | Manual Switch - Span | |
| MS-Spring/MSPR | Multiplex Section Shared Protection Ring | |
| MST | Mountain Standard Time; Multiplex Section Termination | |
| MSTE | Multiplex Section Terminating Equipment | |
| MS-W | Manual Switch - Working | |
| MTA | Multimedia Terminal Adapter | |
| MTBF | Mean Time between Failure | |
| MTIE | Maximum Time Interval Error | |
| MTM | Metro Transport Manager | |
| MTTP | Transparent Connection Termination Point | |
| MTTR | Mean Time to Repair | |
| MTTU | Mean Time to Understand | |
| MTU | Maximum Transmission Unit | |
| MUX | Multiplexer | |
| MUXCVR | Muxceiver | |
| mV | Millivolt | |
| MVOA | Miniature Variable Optical Attenuator | |
| MW | ²Ñ³Ü±ô³Ù¾±°Â²¹±¹±ð® | |
| MZ | Mach-Zehnder | |
| N | ||
| NA | No Alarm; Not Alarmed; Not Applicable; Not Available; Numerical Aperture | |
| NAD | Network Access Domain | |
| NAP | Network Access Point | |
| NAPT | Network Address and Protocol Translation | |
| NAS | Network Access Server; Network Attached Storage | |
| NAT | Network Address Translation | |
| NBI | Northbound Interface | |
| NBK | No Backup | |
| NC | Nodal Controller; Normally Closed (contacts) | |
| NCC | Network Control Center | |
| NCCI | Network Call Correlation Identification | |
| NCP | Nodal Control Point; Nodal Control Processor | |
| NCP&D | Network Capacity Planning and Delivery | |
| NCR | Non-Conformance Report | |
| NCS | Network Computing System; Network Control System; Network Call Signaling | |
| NCTA | National Cable & Telecommunications Association | |
| NDC | National Destination Code | |
| NDF | New Data Flag | |
| NDIS | Network Design and Inventory System | |
| NDMH | Non-Degraded Modem Hours | |
| NDP | Network Discovery Protocol; Neighbor Discovery Protocol | |
| NDSF | Non-Dispersion Shifted Fiber | |
| NDVR | Network Digital Video Recording | |
| NE | Network Element | |
| NEBS | Network Equipment Building Standards; Network Equipment Building Systems | |
| NEC | National Electric Code | |
| NEF | Network Element Function | |
| NE/FE | Near End/Far End | |
| NEG | Negative Terminal | |
| NEID | Network Element Identification | |
| NEIR | Network Element Information Request | |
| NEMA | National Electrical Manufacturers Association | |
| NFS | Networked File System | |
| NGDLC | Next Generation Digital Loop Carrier | |
| NG-L1 | Next Generation Layer 1 | |
| NGNA | Next Generation Network Architecture | |
| NI | Network Interface | |
| NIC | Network Interface Card | |
| NID | Network Interface Device | |
| NIDU | Network Interface Data Unit | |
| NIS | Network Infrastructure Solutions | |
| NIU | Network Interface Unit | |
| NLA | Network Layer Address; Network Layer Agent | |
| NLC | Node Line Card | |
| NLD | Neighbor Link Discovery | |
| NLPI | Network Layer Protocol Identifier | |
| nm | nanometer | |
| NM | Network Management; Network Manager; Network Management; Node Manager | |
| NMA | Network Monitoring and Analysis | |
| NME | Network Management Ethernet | |
| NMF | Node-level Management Function | |
| NML | Network Management Layer | |
| NMS | Network Management System | |
| NN | N key on keyboard for a no response | |
| NNI | Network to Network Interface; Network Node Interface | |
| NNIF | Network to Network Interface | |
| NNM | Network Node Manager | |
| NNTP | Network News Transfer Protocol | |
| NO | Network Object; Normally Open (contacts) | |
| NOC | Network Operations Center | |
| NOCC | Network Operations Control Center | |
| NPC | Network Parameter Control | |
| NPR | Noise Power Ratio | |
| NR | No Reply | |
| NRT | Non-Real Time | |
| NRTL | Nationally Recognized Test Laboratory | |
| NRTVBR | Non Real-Time Variable Bit Rate | |
| NRZ | Non-Return to Zero | |
| ns | Nanosecond | |
| NSA | Non Service Affecting | |
| NSAP | Network Service Access Point | |
| NSI | Network Side Interface | |
| NSN | Nationally Significant Number | |
| NSP | Node Switch Provider; Node Switch Processor | |
| NT | Window New Technology | |
| NTF | No Trouble Found | |
| NTFCNCDE | Notification Codes (TL1) | |
| NTFS | New Technology File System | |
| NTP | Network Time Protocol | |
| NTS | Near Term Storage; Network Time Synchronization | |
| NTSC | National Television Standards Committee | |
| NUT | Non-preemptive Unprotected Traffic | |
| NVM | Non-Volatile Memory | |
| NVRAM | Nonvolatile Random Access Memory | |
| NZDSF | Non-Zero Dispersion Shifted Fiber | |
| O | ||
| OA | Optical Amplifier | |
| OADM | Optical Add/Drop Multiplexer | |
| OAM | Operations, Administration and Maintenance | |
| OAMCell | Operations, Administration and Maintenance Cell | |
| OAMP | Operation, Administration, Maintenance and Provisioning | |
| O-BLSR | Optical-Bidirectional Line Switched Ring | |
| OC | Optical Carrier | |
| OCAP | OpenCable Application Platform | |
| OCH | Optical Channel | |
| OCI | Open Connection Indication | |
| OCT | Octet Count | |
| OC-1 | Optical Carrier level 1, SONET bit rate = 51.84 Mb/s | |
| OC-3 | Optical Carrier level 3, SONET bit rate = 155.52 Mb/s | |
| OC-12 | Optical Carrier level 12, SONET bit rate = 622.08 Mb/s | |
| OC-48 | Optical Carrier level 48, SONET bit rate = 2.488 Gb/s | |
| OC-192 | Optical Carrier level 192, SONET bit rate = 9.953 Gb/s | |
| OC-n | Optical Carrier-number; Optical Carrier where N denotes a multiple of 51.84 Mb/s | |
| OCTU | Optical Channel Transport Unit | |
| OCXO | Oven-Controlled Crystal Oscillator | |
| ODA | Outlet Digital Adapter | |
| ODACS | Optical Data Acquisition and Control System | |
| ODBMS | Object Database Management System | |
| ODF | Optical Distribution Frame | |
| ODPR | Optically Dedicated Protection Ring | |
| ODUk | Optical channel Data Unit where k is 1 or 2 | |
| OEO | Optical-to-Electronic-to-Optical | |
| OEPL | Optical Ethernet Private Line | |
| OEPLAN | Optical Ethernet Private Local Area Network | |
| OEVPL | Optical Ethernet Virtual Private Line | |
| OEVPLAN | Optical Ethernet Virtual Private Local Area Network | |
| OFC | Open Fiber Control; Optical Fiber Communication | |
| OFDM | Orthogonal Frequency Division Multiplexing | |
| OFS | Out of Frame Second | |
| OID | Object Identifier | |
| OIU | Operator Interface Unit; Optical Interface Unit; Office Interface Unit | |
| OLA | Optical Line Amplifier; Optical Link Analysis | |
| OLB | Optical Link Budget | |
| OLM | Optical Link Module | |
| OLMP | Optical Link Management Protocol | |
| OLS | Optical Line System | |
| OLT | Optical Line Termination; Optical Line Terminal | |
| OLTP | OSRP Link Termination Point | |
| OM | Optical Module | |
| OMC | Operation and Maintenance Center | |
| OMG | Object Management Group | |
| OMS | ON-Center Management Suite | |
| ON | Optical Network | |
| ONE | Optical Network Element | |
| ONM | ON-Center Network Manager | |
| ONT | Optical Network Terminal | |
| ONU | Optical Network Unit | |
| OO | Optical-to-Optical | |
| OOB | Out of Band | |
| OOF | Out of Frame | |
| OOK | On-Off Keying | |
| OOM1 | Out of Multi Frame Stage 1 | |
| OOM2 | Out of Multi Frame Stage 2 | |
| OOO | Optical - Optical - Optical | |
| OOR | Out of Range | |
| OOS | Out of Service | |
| OSS-AU | Out of Service-Autonomous | |
| OSS-AUMA | Out of Service-Autonomous and Management | |
| OSS-AURST | Out of Service-Autonomous and Restricted | |
| OOS-MA | Out of Service-Management | |
| OOS-MAANR | Out of Service-Management and Abnormal | |
| OpEx | Operations Expenditure | |
| OPM | Optical Performance Monitoring; Optical Power Meter | |
| OPR | Optical Power Received | |
| OPS/INE | Operations Provisioning System/Intelligent Network Element | |
| OPT | Optical Power Transmit | |
| OPTORL | Optical Return Loss | |
| OPTX AE | OPTX Automation Engine | |
| OPTX NM | OPTX Network Manager | |
| OpUk | Optical channel payload Unit where k is 1 or 2 | |
| OPVC | Optical channel Payload Virtual Container (timeslot) | |
| ORB | Object Request Broker | |
| ORIG | Original; Originating | |
| ORL | Optical Return Loss | |
| ORP | Optical Routing Protocol | |
| OS | Operating System | |
| OSA | Optical Spectrum Analyzer | |
| OSC | Optical Supervisory Channel; Optical Service Channel | |
| OSDS | Operations Systems Data Server | |
| OSGI | Open Services Gateway Initiative | |
| OSHA | Occupational Safety and Health Act | |
| OSI | Open Systems Interconnection | |
| OSM | OSC Splitter Module | |
| OSMINE | Operations Systems Modifications for the Integration of Network Elements | |
| OSNR | Optical Signal-to-Noise Ratio; Open Signal-to-Noise Ratio | |
| OSP | Optical Signaling Protocol; Outside Plant | |
| OSPF | Open Shortest Path First | |
| OSPR | Optically Shared Protection Ring | |
| OSRP | Optical Signaling and Routing Protocols | |
| OSS | Operations Support System | |
| OSSAN | Operations Support System Access Nodes | |
| OSWF | On-site Work Force | |
| OTC | Operations Technical Center; Optical Transport Card | |
| OTDR | Optical Time Domain Reflectometer | |
| OTGR | Operations Technology Generic Requirements | |
| OTN | Optical Transport Network | |
| OTS | Optical Transport System | |
| OTS RPTR | OTS Repeater | |
| OTU | Optical Transport Unit | |
| OUI | Organizationally Unique Identifier | |
| OUNI | Optical User Network Interface | |
| O-UPSR | Optical-Unidirectional Path Switched Ring | |
| OUSM | Optical Utility Services Manager | |
| OUSP | Optical Utility Services Platform | |
| OW | Order Wire | |
| OXC | Optical Cross Connect | |
| P | ||
| P2P | Peer to Peer | |
| PA | Port Adapter; Pre-Amplifier | |
| PAD | Power Attenuation Device | |
| PAN | Personal Area Networking | |
| PARP | Proxy ARP | |
| PAT | Program Association Table | |
| PAX | Path Adaptation and X-Connect | |
| PB | Petabyte | |
| PBX | Private Branch Exchange | |
| PBOR | Primary-Backup Object Replication | |
| PC | Personal Computer; Physical Contact; Processor Card | |
| PCA | Protection Channel Access | |
| PCB | Printed Circuit Board | |
| PCC | Processor Communication Channel | |
| PCI | Peripheral Component Interconnect | |
| PCN | Program Change Notice; Product Change Notice | |
| PCM | Pulse Code Modulation | |
| PCMCIA | Personal Computer Memory Card Interface Adaptor | |
| PCMM | PacketCable Multimedia | |
| PCO | Pre-Conditioned Order | |
| P-Code | Product Code | |
| PCR | Peak Cell Rate | |
| PDA | Personal Digital Assistant | |
| PDAP | Power Distribution and Alarm Panel | |
| PDC | Passive Dispersion Compensator | |
| Portable Document Format | ||
| PDH | Pleisiochronous Digital Hierarchy | |
| PDI | Payload Defect Indication | |
| PDL | Polarization Dependent Loss | |
| PDP | Policy Decision Point | |
| PDU | Power Distribution Unit; Protocol Data Unit | |
| PEG | Public, Education, Government | |
| PEM | Processor Enhancement Module; Processor Element Module | |
| PEP | Policy Enforcement Point | |
| PESQ | Perceptual Evaluation of Speech Quality | |
| PFE | Path Far End | |
| PFM | Packet Forwarding Module | |
| PFO | Premium Feature Open | |
| PG | Peer Group; Protection Group | |
| PGID | Peer Group Identifier | |
| PGL | Peer Group Leader | |
| PHY | Physical Layer Device; Physical | |
| PIC | Programmable Interrupt Controller | |
| pid | Password Identifier | |
| PID | Personally Identifiable Data; Protocol Identifier; Packet Identifier; Personal Identification | |
| PIF | Packet Interface FPGA | |
| PIN | Photo Intrinsic; Positive-Intrinsic Negative; Personal Identification Number | |
| PING | Packet Internet Groper | |
| PIP | Plug-In Provisioning | |
| PJ | Pointer Justification | |
| PL | Packet Loss | |
| PLC | Packet Loss Concealment | |
| PLCN | Pilot Line Change Notification | |
| PLCP | Physical Layer Convergence Protocol | |
| PLD | Programmable Logic Device | |
| PLL | Phase Locked Loop | |
| PLM | Payload Label Mismatch | |
| PLM-P | Payload Label Mismatch - Path | |
| PLM-V | Payload Label Mismatch - VT | |
| PLN | PNNI Logical Node | |
| PLO | Path Layer Overhead | |
| PM | Performance Management; Performance Monitoring; Program Manager; Project Manager | |
| PMA | Power Management Algorithm | |
| PMBB | Performance Monitoring Building Block | |
| PMD | Polarization Mode Dispersion | |
| PMDC | PMD Compensator | |
| PMM | Power Management Module | |
| PMP | Point-to-MultiPoint | |
| PN | Physical Node | |
| PNC | Physical Node Controller | |
| PNNI | Private Network-to-Network Interface; Private Network Node Interface | |
| PO | Purchase Order | |
| POH | Path Overhead | |
| PON | Passive Optical Network | |
| POP | Point of Presence | |
| POR | Power on Reset | |
| POS | Packet over SONET; Positive Terminal | |
| POST | Power on Self Test | |
| POTS | Plain Old Telephone Service | |
| PPC | Power PC | |
| PPD | Partial Packet Discard | |
| PPJC | Positive Pointer Justification Count | |
| PPL | Point-to-Point Link | |
| ppm | Pulse Position Modulation; Pulses per Million | |
| PPM | Parts per Minute; Parts per Million; Pulses per Million | |
| Pport | Physical port | |
| PPP | Point-to-Point Protocol | |
| PPS | Path Protection Switched; Pulses per Second | |
| PPT | Power Passing Tap | |
| PRBS | Pseudo Random Bit Sequence | |
| PRC | Primary Reference Clock | |
| PRI | Primary Rate Interface | |
| PROM | Programmable Read Only Memory | |
| PROT | Protocol; Protection | |
| PRNG | Pseudo Random Number Generators | |
| PRS | Primary Reference Source | |
| PS | Power Supply; Policy Server | |
| ps/nm-km | Pico-second | |
| PSA | PacketCable Service Agreement | |
| PSBF | Protection Switching Byte Failure | |
| PSC | Protection Switching Count | |
| PSD | Protection Switching Duration | |
| PSEL | Presentation Suite | |
| PSI | Program Specific Information | |
| PSL | Path Signal Label | |
| PSM | Persistent Stored Module | |
| PSN | Packet Switch Node; Packet Switched Network | |
| P-SNC | Permanent SNC | |
| PSQM | Perceptual Speech Quality Measurement | |
| PSR | Protection Side Regeneration; Path Switched Ring | |
| PST | Primary State; Pacific Standard Time | |
| PSTN | Public Switched Telephone Network | |
| PSU | Power Supply Unit; Packet Switch Unit | |
| PT | Pass-Through; Payload Type | |
| PTE | Path Terminating Equipment | |
| PTI | Payload Type Indicator | |
| PTP | Physical Termination Point; Point-To-Point; Path Termination Point | |
| PTSE | PNNI Topology State Element | |
| PTSP | PNNI Topology State Packet | |
| PV | Protocol Violation | |
| PVC | Permanent Virtual Circuit; Poly Vinyl Chloride; Private Virtual Circuit | |
| PVR | Personal Video Recorder | |
| PWB | Printed Wire Board | |
| PWM | Pulse Width Modulation | |
| PWR | Power | |
| Q | ||
| Q3 | Telecommunications Management Network (TMN) Interface | |
| QAM | Quadrature Amplitude Modulation | |
| QL | Quality Level | |
| QMC | QUICC Multichannel Controller | |
| QoS | Quality of Service | |
| QPSK | Quadrature Phase Shift Keying | |
| QUICC | Quad Integrated Communications Controller | |
| R | ||
| R&D | Research and Development | |
| R/W | Read/Write | |
| RADIUS | Remote Authentication Dial-In User Service | |
| RAI | Remote Alarm Indication | |
| RAID | Redundant Array of Inexpensive Disk; Redundant Array of Independent Disk | |
| RAIG | Resource Availability Information Group | |
| RAM | Random Access Memory | |
| RAN | Regional Area Network | |
| RBF | Reconfigurable Blocking Filter | |
| RBOC | Regional Bell Operating 91ÌÒÉ« | |
| RBM | Regional Business Manager | |
| RBW | Resolution Bandwidth | |
| RCC | Routing Control Channel | |
| RCV | Receiver | |
| RCVR | Receiver | |
| RDF | Rate Decrease Factor | |
| RDI | Remote Defect Indication | |
| RDI-L | Remote Defect Indication - Line | |
| RDI-P | Remote Defect Indication - Path | |
| RED | Random Early Detection; Random Early Discard | |
| REF | Reference | |
| REI | Remote Error Indication | |
| REI-L | Remote Error Indication - Line | |
| REI-P | Remote Error Indication - Path | |
| Rev. | Revision | |
| RF | Radio Frequency | |
| RFC | Request for Comment | |
| RFI | Radio Frequency Interference; Remote Failure Indication; Request for Information | |
| RFI-L | Remote Failure Indication (detected at the line-layer) | |
| RFI-P | Remote Failure Indication (detected at the path-layer) | |
| RG | Residential Gateway | |
| R.H. | Relative Humidity | |
| RHC | Regional Holding 91ÌÒÉ« | |
| RIB | Routing Information Base | |
| RIN | Relative Intensity Noise | |
| RIP | Routing Information Protocol | |
| RJ | Registered Jack | |
| RKS | Record Keeping Server | |
| RMA | Return Material Authorization; Replace Material Authorization | |
| RMAN | Recovery Manager | |
| RMI | Remote Method Invocation | |
| RMS | Root Mean Square | |
| RNR | Not Ready to Receive; Remote Failure Indication | |
| ROADM | Re-configurable Optical Add/Drop Multiplexer | |
| ROC | Regional Operations Center | |
| ROI | Return on Investment | |
| ROM | Read Only Memory | |
| RPM | Revolutions per Minute | |
| RPR | Resilient Packet Ring | |
| RR | Ready to Receive; Reverse Request | |
| RRB | Reliability Review Board | |
| RRO | Record Route Object | |
| RR-R | Reverse Request - Ring | |
| RR-S | Reverse Request - Span | |
| RS | Regenerator Section; Reed-Solomon | |
| RS-E | Ring Switch - East | |
| RSOH | Regenerator Section Overhead | |
| RSP | Route Switch Processor | |
| RST | Regenerator Section Terminating | |
| RSVP | Resource Reservation Protocol | |
| RSVP-TE | Resource Reservation Protocol with Traffic Engineering | |
| RS-W | Ring Switch - West | |
| RT | Remote Terminal; Real Time | |
| RTC | Real-Time Clock | |
| RTI | Real-Time Ingest | |
| RTN | Return (voltage return) | |
| RTOS | Real-Time Operating System | |
| RTP | Routing Table Protocol; Real-Time Transport Protocol; Routine Task Procedure | |
| RTRV | Retrieve | |
| RTS | Ready to Send; Request to Send; Real Time Operation System | |
| RTSP | Real Time Streaming Protocol | |
| RTT | Round-trip Time | |
| RTU | Right to Use | |
| RTVBR | Real-Time Variable Bit Rate Traffic | |
| RU | Rack Unit | |
| RW | Rewind | |
| RWA | Routing and Wavelength Assignment | |
| R/W | Read/Write | |
| RX | Receive | |
| Rx Line | Receive Line | |
| RZ | Return to Zero | |
| RZ-DPSK | Return to Zero Differential Phase Shift Keying | |
| S | ||
| s | Second | |
| s.f. | Square Foot | |
| S/IMP | Signal to Impulse Ratio | |
| S/N | Signal to Noise Ratio | |
| SA | Service-Affecting | |
| SAAL | Signaling ATM Adaptation Layer | |
| SABLIME | Product Administration System (AT&T) | |
| SADM04-e | SONET/SDH Add/Drop Multiplexer (ONLINE Edge Platform) | |
| SAN | Storage Area Network | |
| SAP | Secondary Audio Program | |
| SAR | Segmentation and Reassembly | |
| SARP | Switching Address Resolution Protocol | |
| SAS | Severely Errored Frame and AIS Seconds | |
| SASE | Standalone Synchronization | |
| SATA | Serial AT Attachment | |
| SATT | Synchronization, Alarms, and Telemetry Termination | |
| SAW | Surface Acoustic Wave | |
| SBLK | Errored Superblocks | |
| SBS | Stimulated Brillouin Scattering | |
| SBV | Switched Broadcast Video | |
| SBW | Signal Bandwidth | |
| SC | Service Channel; Square Connector; Shelf Controller | |
| SCC | Serial Communications Controller; Serial Communications Channels | |
| SCCI | Small Computer System Interface | |
| S-CDMA | Synchronous Code Division Multiple Access | |
| SCM | Service Channel Modem; Sub-carrier Multiplexing | |
| SCN | Service Channel Network; Shared Content Network | |
| SCR | Sustainable Cell Rate; Silicon Controlled Rectifier | |
| SCSI | Small Computer System Interface | |
| SCTE | Society of Cable Telecommunications Engineers | |
| SD | Signal Degrade; Signal Detect; Standard Definition | |
| SDCC | Section Data Communications Channel | |
| SDH | industries_cable Synchronous Digital Hierarchy | |
| SDI | Secure Digital Interface; Serial Digital Interface | |
| SDL | Synchronous Data Link; Synchronous Delay Line | |
| SDLC | Synchronous Data Link Control | |
| SDMH | Severely Degraded Modem Hours | |
| SDP | Session Description Protocol | |
| SD-P | Signal Degrade - Path | |
| SD-R | Signal Degrade - Ring | |
| SDRAM | Synchronized Dynamic Random Access Memory | |
| SD-S | Signal Degrade-Span | |
| SDTV | Standard Definition Television | |
| SDU | Service Data Unit | |
| SE | Systems Engineer | |
| SEAL | Simple and Efficient Adaptation Layer | |
| SEC | Secondary | |
| SEF | Severely Errored Framing | |
| SEFS | Severely Errored Frame Seconds | |
| SEFS-S | Severely Errored Framing Seconds - Section | |
| SEM | Service Entitlement Manager | |
| SEMS | Severely Errored Multi-frame Seconds | |
| SerDes | Serializer/DeSerializer | |
| SES | Severely Errored Seconds | |
| SES-L | Severely Errored Seconds - Line | |
| SES-LFE | Severely Errored Seconds - Line Far End | |
| SES-P | Severely Errored Seconds - Path | |
| SES-PFE | Severely Errored Seconds - Path Far End | |
| SESR | Severely Errored Second Ratio | |
| SES-RS | Severely Errored Seconds - Regenerator Section | |
| SES-S | Severely Errored Seconds - Section | |
| SES-V | Severely Errored Seconds - VT | |
| SES-VFE | Severely Errored Seconds - VT Far End | |
| SETS | Synchronous Equipment Timing Source | |
| SF | Signal Failure; Super Frame | |
| SFD | Start of Frame Delimiter | |
| SFDADM02-e | SONET/SDH Framed Data Add/Drop Multiplexer (ONLINE Edge Platform) | |
| SFF | Small Form Factor (connector) | |
| SFO | Sync Frequency Offset | |
| SFP | Small Form-factor Pluggable | |
| SF-R | Signal Failure - Ring | |
| SF-S | Signal Failure - Span | |
| SG | Signaling Gateway | |
| SGC | Signaling Gateway Controller | |
| sh | Bourne Shell | |
| SHx | Shelf Number | |
| SI | Serial Interface; Service Independent | |
| SIC | System Integrity Control; Standard Industrial Classification | |
| SID | System Identification number; Source Identifier | |
| SIF | SONET Interoperability Forum; Switch Interface FPGA | |
| SIM | Service Interface Module | |
| SIP | Session Initiation Protocol | |
| SLA | Service Level Agreement | |
| SLIP | Serial Line Internet Protocol | |
| SLM | Service Layer Manager | |
| SLOSS | Synchronization Loss | |
| SLR | Service Level Report | |
| SM | Single Mode; Switching Module; Shelf Manager | |
| SMB | Small and Medium Business | |
| SMC | Serial Management Controllers; Standard Management Committee | |
| SMDS | Switched Multimegabit Data Service | |
| SME | Small and Medium Enterprise | |
| SMF | Single Mode Fiber | |
| SMIR | Single Mode Intermediate Reach | |
| SML | Service Management Layer | |
| SMLR | Single Mode Long Reach | |
| SMM | Service Mediation Module | |
| SMON | Switch Monitor | |
| SMOP | Service Method of Procedure | |
| SMS | Service Management Suite | |
| SMT | Surface Mount Technology; Self-Monitoring Task | |
| S-MTA | Standalone Multimedia Terminal Adaptor | |
| SNA | Systems Network Architecture | |
| SNC | Subnetwork Connection; Subnetwork Controller | |
| SNCP | Subnetwork Connection Protection | |
| SNCP/I | Subnetwork Connection Protection/Inherent monitoring | |
| SNCP/N | Subnetwork Connection Protection/Non-intrusive monitoring | |
| SNM | Switching Network Manager | |
| SNMP | Simple Network Management Protocol | |
| SNP | Sequence Number Protection | |
| SNR | Signal-to-Noise Ratio | |
| SNTP | Simple Network Time Protocol | |
| SOA | Semiconductor Optical Amplifier | |
| SOADM | Select Optical Add/Drop Multiplexer | |
| SOF | Start of Frame | |
| SOH | Section Overhead; State of Health | |
| SOHO | Small Office/Home Office | |
| SONET | industries_cable Synchronous Optical Network | |
| SOP | Standard Operating Procedure | |
| SP | Shelf Processor; Shelf Pump | |
| SPC | SONET Permanent Circuit | |
| SPE | Synchronous Payload Envelope | |
| SPF | Shortest Path First | |
| SPI | Serial Peripheral Interface; Service Provider Interface | |
| SPM | Self-Phase Modulation | |
| SPR/SPRing | Shared Protection Ring | |
| SPTP | Service Path Termination Point | |
| SPVC | Soft Permanent Virtual Connection; Soft Permanent Virtual Circuit | |
| SQL | Structured Query Language | |
| SR | Short Reach (fiber) | |
| SRAM | Static Random Access Memory | |
| SRD | Software Release Document | |
| SRN | Software Release Notice | |
| SRS | Stimulated Raman Scattering | |
| SRTS | Synchronous Residual Time Stamp | |
| SRVEFF | Service Affecting (TL1) | |
| SSB | Single Sideband | |
| SSCOP | Service Specific Connection Oriented Protocol | |
| SSCS | Service-Specific Convergence Sublayer | |
| SSEL | Session Selector | |
| SSF | Server Signal Failure | |
| SSL | Secure Sockets Layer | |
| SSM | Synchronization-Status Messages | |
| SSMF | Standard Single Mode Fiber | |
| SST | Secondary Service State | |
| SSTUR | Site-Specific Turn-Up Report | |
| SSU | Synchronization Supply Unit | |
| ST | Straight Terminus; Straight Tip | |
| ST1 | Stratum 1 | |
| ST2 | Stratum 2 | |
| ST3 | Stratum 3 | |
| ST3E | Stratum 3 Enhanced | |
| ST4 | Stratum 4 (Asynchronous) | |
| STB | Set-Top Box | |
| STC | Stacking and Timing Card | |
| STE | Section Terminating Equipment; Section Terminating Element | |
| STII (2) | Type of optical connector | |
| STM | Synchronous Transfer Mode | |
| STM-0 | Synchronous Transfer Mode level 0, SDH bit rate = 51.84 Mb/s | |
| STM-1 | Synchronous Transfer Mode level 1, SDH bit rate = 155.52 Mb/s | |
| STM-4 | Synchronous Transfer Mode level 4, SDH bit rate = 622.08 Mb/s | |
| STM-16 | Synchronous Transfer Mode level 16, SDH bit rate = 2488.32 Mb/s | |
| STM-64 | Synchronous Transfer Mode level 64, SDH bit rate = 9953.28 Mb/s | |
| STM-n | Synchronous Transport Module "n" | |
| STM-nC | Synchronous Transport Module of level n concatenated | |
| STMX | SONET/SDH Thin Multiplexer | |
| STP | Spanning Tree Protocol; Shielded Twisted Pair | |
| STS | Synchronous Transport Signal | |
| STS-1 | Synchronous Transport Signal Level 1 | |
| STS-3 | Synchronous Transport Signal Level 3 | |
| STS-3c | Synchronous Transport Signal Level 3, concatenated | |
| STS-n | Synchronous Transport Signal "n" | |
| STS-Nc | Contiguous Concatenation of N STS-1 SPEs | |
| STS-N-Xv | Virtual Concatenation of X STS-N SPEs | |
| STU | Secure Telephone Unit; Synchronized, Traceability Unknown; Stratum Traceability Unknown | |
| STU-P | Stratum Traceability Unknown-Provisioned | |
| SVC | Switched Virtual Circuit | |
| SVCC | Switched Virtual Channel Connection | |
| SVOD | Subscription Video on Demand | |
| SVP | Secure Video Processor | |
| SVPC | Switched Virtual Path Connection | |
| SW | Software | |
| SWCA | Split Working Channel Access | |
| SWID | Software Identifier | |
| SWOD | Software ODACS | |
| SX | Short Reach as in 1000Base-SX | |
| SYNC | Synchronization | |
| SYNCIO | Synchronized Input/Output | |
| SYSLOG | System Log | |
| T | ||
| T1 | Service or line operation at the DS-1 rate | |
| T3 | Digital Carrier System for DS3 Signals | |
| TAC | Transport Aggregated Circuit; Technical Assistance Center | |
| TADR | Target Address | |
| TADRMAP | Target Address Map | |
| TAP | Test Access Port; Technician Access Port | |
| TARP | Target Identifier Address Resolution Protocol | |
| TB | Terabyte | |
| TBOS | Telemetry Byte Oriented Serial Protocol | |
| TBU | Transport Bandwidth Unit | |
| TBUS | Timing Bus | |
| TC | Transmission Convergence; Transport Complex; Transport Channel | |
| TCA | Threshold Crossing Alert; Timing Control and Access | |
| TCBE | Total Corrected Bit Error | |
| TCM | Trellis Coded Modulation; Transport Channel Members | |
| TCMO | Transport Complex Managed Object | |
| TCP | Transmission Control Protocol; Trouble Cleaning Procedure | |
| TCP/IP | Transmission Control Protocol/Internet Protocol | |
| TCTP | Transparent Connection Termination Point | |
| TD | Traffic Director | |
| TDEV | Time Deviation | |
| TDM | Time Division Multiplexing | |
| TE | Terminal Equipment | |
| TEAL | CoreDirector® Events, Alarms, and Logging | |
| TEC | Thermo-Electric Cooler | |
| TED | Traffic Engineering Database | |
| TEI | Terminal Endpoint Identifier; Terminal Equipment Identifier | |
| Telco | Telephone 91ÌÒÉ« | |
| TELR | Talker Echo Loudness Rating | |
| TEO | Telephone Equipment Order | |
| TERM | Termination | |
| TFT | Thin Film Transistor | |
| TFTP | Trivial File Transfer Protocol | |
| TG | Timing Generator | |
| TGCP | Trunking Gateway Control Protocol | |
| TGS | Time Generation System | |
| THEC | Corrected Type Header Error Correction Code | |
| THz | TeraHertz (1012 hertz) | |
| TIA | Telecommunications Industry Association | |
| TID | Target Identification; Terminal Identification | |
| TIE | Time Interval Error | |
| TIM | Trace Identifier Mismatch; Transmit Intermediate Multiplexer | |
| TIM-S | Trace Identifier Mismatch - Section | |
| TIRKS | Trunk Integrated Record Keeping System | |
| TISSA | Time Space Switch Application-Specific Integrated Circuit | |
| TKIP | Temporal Key Integrity Protocol | |
| TL-1 CLI | Transaction Language One, Command Line Interface | |
| TL-1 | Transaction Language 1 | |
| TLI | Transaction Language Command Line Interface | |
| TLC | Transport Logical Connection | |
| TLS | Transparent LAN Services | |
| TLSR | Transoceanic Line Switched Ring | |
| TLV | Type-Length-Value | |
| TM | Timing Module; Transaction Manager | |
| TML | Telephony Markup Language | |
| TMN | Telecommunications Management Network | |
| TMO | Trans Metro Optical (platform) | |
| tmout | Time Out | |
| tmper | Time Period | |
| TMUX | Terminal Multiplexer | |
| TNL | Ethernet Tunneling | |
| TNM | Transport Network Management | |
| TOD | Television on Demand | |
| ToD | Time of Day | |
| TOH | Transport Overhead | |
| TOP | Task Oriented Practice; Task Oriented Procedure | |
| TOS | Type of Service | |
| TP | Termination Point | |
| TPFI | Timing Plane Fault Isolation | |
| TR | Technical Reference | |
| TRIB | Tributary | |
| tRTO | TCP Retransmit Timeout | |
| TrTOH | Transparent Transport Overhead | |
| TS | Time Slot; Time Stamp; Time Synchronization | |
| TSA | Time Slot Assignment | |
| TSD | Transport System Division | |
| TSE | Topology State Element | |
| TSEL | Transport Selector | |
| TSF | Transport Signal Failure | |
| TSG | Timing Signal Generator | |
| TSI | Time Slot Interchange; Time Switch Interchange | |
| TSR | Technical Service Representative | |
| TSX | Time-Space Switch ASIC | |
| TTE | Transparent Terminal Equipment | |
| TTL | Transistor Transistor Logic; Time to Live | |
| TTP | Trail Termination Point | |
| TTTP | Transparent Trail Termination Point | |
| TU | Tributary Unit; Transmission Unit | |
| TUG | Tributary Unit Group | |
| TUG-n | Tributary Unit Group, level n | |
| TU-n | Tributary Unit, level n | |
| TV | Television | |
| TW | TrueWave | |
| TWC | TrueWave Classic | |
| Tx Line | Transmit Line | |
| TX | Transmit | |
| U | ||
| UART | Universal Asynchronous Receiver/Transmitter | |
| UAS | Unavailable Seconds | |
| UAS-L | Unavailable Seconds - Line | |
| UAS-LFE | Unavailable Seconds - Line Far End | |
| UAS-P | Unavailable Seconds - Path | |
| UAS-PFE | Unavailable Seconds - Path Far End | |
| UAS-RS | Unavailable Seconds - Regenerator Section | |
| UAS-S | Unavailable Seconds - Section | |
| UAS-V | Unavailable Seconds - VT | |
| UAS-VFE | Unavailable Seconds - VT Far End | |
| UASL | Unavailable Second Count-Line | |
| UASP | Unavailable Second Count-Path | |
| UAT | Unavailable Time | |
| UB | Uncorrected Block | |
| UBRVBR | Unspecified Bit Rate Variable Bit Rate | |
| UBR | Undefined Bit Rate; Unspecified Bit Rate | |
| UC | User Channel | |
| UCA | Unswitched Channel Access | |
| UCBE | Uncorrectable Block Error | |
| UCD | Upstream Channel Descriptor | |
| UD | Unconditional Disconnect | |
| UDLR | Unidirectional Link Routing | |
| UDP | User Datagram Protocol | |
| UDR | Unconditional Disconnect Response | |
| UEQ | Unequipped | |
| UFEC | Ultra Forward Error Correction | |
| UGC | Universal Gateway Carrier | |
| UGS | Unsolicited Grant Service | |
| UHD | Ultra High Density | |
| UHF | Ultra High Frequency | |
| UI | User Interface | |
| UID | User Identifier | |
| UITS | Unacknowledged Information Transfer Service | |
| UL | Underwriters Laboratories | |
| ULH | Ultra Long Haul | |
| ULSDCC | Upper Layer Section Data Communications Channel | |
| UNEs | Unbundled Network Elements | |
| UNEQ | Unequipped Path; Unequipped | |
| UNEQ-P | Unequipped Path | |
| UNEQ-V | Unequipped VT | |
| UNI/UNIF | User Network Interface | |
| UNII | Unlicensed National Information Infrastructure | |
| UOG | Universal OSS Gateway | |
| UPC | Ultra Physical Contact; Universal Packet Carrier; Usage Parameter Control | |
| UPnP | Universal Plug and Play | |
| UPS | Uninterrupted Power Supply | |
| UPSR | Unidirectional Path Switched Ring | |
| URI | Universal Resource Identifier | |
| URL | Universal Resource Locator | |
| US | Upstream | |
| USA | Universal Shelf Amplifier | |
| USB | Universal Serial Bus | |
| USEPA | United States Environmental Protection Agency | |
| UTC | Universal Time Coordinated; Universal Transport Carrier | |
| UTOPIA | Universal Test and Operations Physical Interface for ATM | |
| UTP | Unprotected Termination Point; Unshielded Twisted Pair | |
| UV | Ultraviolet | |
| UVC | Universal Voice Carrier; Universal Video Carrier | |
| V | ||
| V | Voltage | |
| V/A | Video/Audio | |
| VAC | Volts Alternating Current | |
| VAD | Voice Activity Detection | |
| VAP | Virtual Access Partitioning | |
| VBI | Vertical Blanking Interval | |
| VBR | Variable Bit Rate | |
| VC | Virtual Circuit; Virtual Channel; Virtual Container; Virtual Concatenation | |
| VC-N | Virtual Container Level N (N=11, 12, 2, 3, 4) | |
| VC-N-Xc | Contiguous Concatenation of X Virtual Containers at Level N | |
| VC-N-Xv | Virtual Concatenation of X Virtual containers at Level N | |
| VCAT | Virtual Concatenation | |
| VCC | Virtual Channel Connection | |
| VCG | Virtual Concatenation Group | |
| VCI | Virtual Channel Identifier | |
| VCL | Virtual Channel Link | |
| VCM | Virtual Concatenation-group Member | |
| VCO | Voltage Controlled Oscillator | |
| VCR | Video Cassette Recorder | |
| VCSEL | Vertical Cavity Surface-Emitting Laser | |
| VCXO | Voltage Controlled Crystal Oscillator | |
| VDC | Volts Direct Current | |
| VDSL | Very-high-bit-rate Digital Subscriber Line | |
| VF | Virtual Fiber; Virtual Facility | |
| VFTP | Virtual Facility Termination Point | |
| VG | Virtual Group | |
| VGA | Variable Gain Amplifier | |
| VHF | Very High Frequency | |
| VLAN | Virtual Local Area Network | |
| VLR | Very Long Reach | |
| VLSR | Virtual Line Switched Ring | |
| VM | Voice Mail; Virtual Memory | |
| VOA | Variable Optical Attenuator | |
| VOD | Video on Demand | |
| VoIP | Voice over Internet Protocol | |
| VOM | Volt-Ohm Meter | |
| VOQ | Virtual Output Queuing | |
| VOW | Voice Order Wire | |
| VP | Virtual Path | |
| VPC | Virtual Path Connection | |
| VPCI | Virtual Path Connection Identifier | |
| VPG | Virtual Path Group | |
| VPI | Virtual Path Identifier | |
| VPI/VCI | Combined, VPI and VCI identify a connection on an ATM Network | |
| VPL | Virtual Path Link | |
| VPLS | Virtual Private LAN Service | |
| VPN | Virtual Private Network | |
| VPSP | Virtual Path Switch Protection | |
| VRRP | Virtual Router Redundancy Protocol | |
| VSA | Virtual-Scheduling Algorithm; Vector Signal Analyzer | |
| VSAT | Very Small Aperture Terminal | |
| VSI | Vendor-Specific Information | |
| VSR | Very Short Reach | |
| VT | Virtual Tributary | |
| VTG | Virtual Tributary Group | |
| VT-100 | Terminal Emulation System | |
| V-UNI | Virtual User Network Interface | |
| W | ||
| W | Watt; Working | |
| WAD | Wavelength Add and Drop | |
| WAN | Wide Area Network | |
| WB | Working Band; Westbound | |
| WCA | Working Channel Access | |
| WCI | Wavelength Converter Interface | |
| WCI RT | Wavelength Converter Interface Rate Tunable | |
| WCIRT-e | Wavelength Converter Interface Rate Tunable (ONLINE Edge Platform) | |
| WCSS | WDM Capable Switching System | |
| WDM | Wavelength Division Multiplexing | |
| WDT | Watchdog timer | |
| W-DCS | Wideband Digital Cross-Connect System | |
| WECA | Wireless Ethernet Compatibility Alliance | |
| WEP | Wired Equivalency Privacy | |
| WFA | Workforce Automation | |
| WFM | Workforce Management | |
| WFQ | Weighted Fair Queuing | |
| WIF | Wide Area Network Interface | |
| WiFi | Wireless Fidelity | |
| WiMedia | An alliance for Wireless Multimedia | |
| WLAN | Wireless Local Area Network | |
| WM9 | Windows Media Player Version 9 | |
| WPA | Wireless (WiFi) Protected Access | |
| WPS | Working/Protect Splitter | |
| WSS | Wavelength Selective Switch | |
| WRED | Weighted Random Early Discard; Weighted Random Early Detection | |
| WTR | Wait to Restore | |
| WWN | World Wide Name | |
| X | ||
| X.25 | Packet Switched Communications Interface | |
| XC | Cross Connect | |
| XCVR | Transceiver | |
| XDSL | See DSL (Digital Subscriber Line) | |
| XFP | 10 Gb/s small form-factor pluggable transceiver | |
| XML | Extensible Markup Language | |
| XMTR | Transmitter | |
| XPM | Cross-Phase Modulation | |
| Z | ||
| ZAC | Zero Administration Client | |
| ZWP | Zero Water Peak | |