| Keyword | Description |
|---|---|
| (57 to 66 GHz) | - |
| 2-WIRE | - |
| 3,1 KHZ | 3,1 kHz audio |
| 3D Ray-Tracing | - |
| 3DTV | |
| 3G | Third Generation |
| 3GPP | Third Generation Partnership Project |
| 3GPP Access | - |
| 3GPP2 | Third Generation Partnership Project 2 |
| 3PTY | Three party (supplementary service) |
| 464XLAT | - |
| 4G | - |
| 4-WIRE | - |
| 5G | Cellular technology beyond LTE, IMT-2020 conformant |
| 5GMS | - |
| 60 GHz | - |
| 6G | Cellular technology beyond 5G, IMT-2030 conformant |
| 6rd | - |
| 6TiSCH | - |
| 7 KHZ | 7 kHz audio |
| AAL | ATM Adaptation Layer |
| AAS | Active Antenna Systems |
| Abstracted Network Information | - |
| Acceleration | - |
| ACCESS | - |
| access control | - |
| Access Profile | - |
| accessibility | can be accessed by users with disabilities |
| accessible meetings | - |
| accountability | |
| ACOUSTIC | cf. coupling, etc |
| acronym | - |
| ACT | Asynchronous Contact Tracing |
| ADAPTION | Adaption (adaptation), terminal, rate, etc |
| ADDRESSING | Addressing, numbering, routeing |
| ADMINISTRATION | - |
| ADSL | Asymetrical Digital Subscriber Line |
| ADSL2 | |
| ADSL2plus | |
| Advertisement | - |
| AERONAUTICAL | cf. terrestrial, maritime, satellite, etc. |
| AFA | Autonomous Frequency Assignment |
| AFTR | - |
| Age verification | |
| AGEING | cf. Human Factors |
| agentic AI | - |
| agents | - |
| Agriculture | - |
| AI | Artificial Intelligence |
| AI model | Artificial Intelligence Model |
| AI-native | |
| AIP | Additional Information Presentation (supplementary service) |
| air flow | |
| AIR INTERFACE | Air Interface for radiocommunications |
| Air Traffic Management | Air Traffic Management |
| ALARM | - |
| ALGORITHM | (security, encryption, ...) |
| AM | Amplitude Modulation |
| AMATEUR | Commercially available amateur radio equipment |
| AMBIENCE | Ambience listening (supplementary service) |
| AMPLIFICATION | - |
| AMRD | Autonomous Maritime Radio Devices |
| AMSS | Aeronautical Mobile Satellite Service |
| AN | Access Network |
| ANALOGUE | - |
| Analysis | - |
| ANF | Additional Network Feature |
| anonymity | - |
| Anonymous Communication Reject | ACR |
| ANTENNA | Antenna, aerial |
| AOC | Advice of Charge |
| AP | Access Priority (supplementary service) |
| API | Application Programme Interface |
| APM | Application Transport Mechanism (SS7) |
| Application | - |
| application layer | |
| application profile | |
| AR Cloud | - |
| ARCHITECTURE | inc. reference models, etc |
| ARCU model | - |
| AREA SELECT | Area selection (supplementary service) |
| artificial intelligence | - |
| ASCI | Advanced Speech Call Items |
| ASiC | Associated Signature Containers |
| ASN.1 | Abstract Syntax Number one |
| assessment | - |
| Assistive Listening | - |
| assurance | - |
| ATM | Asynchronous Transfer Mode |
| ATS | Abstract Test Suite |
| ATS_GR FILE | Seperate ATS graphical file exists |
| ATS_MP FILE | Seperate ATS mp file exists |
| Attribute Attestation | - |
| Audience | - |
| AUDIO | - |
| audio frequency induction loop | - |
| audio-PMSE | |
| AUDIOTEX | - |
| Augmented Reality | - |
| AUTH | Call authorised by dispatcher (supplementary service) |
| authentication | - |
| authorization | |
| automation | - |
| Automotive | - |
| Autonomic Networking | - |
| autonomous | - |
| Autonomous Network | - |
| AVAILABILITY | QoS characteristic |
| AVI | AudioVisual Information |
| award criteria | |
| B2B | Business to business |
| B2C | Business to customer |
| B4 | - |
| Back haul | - |
| backhaul | - |
| bandwidth | |
| BASE STATION | cf. radio |
| BASIC | cf. Call, Service, Access, etc. |
| battery | - |
| BC | Bearer Capability information element (ISDN) |
| B-CHANNEL | Bearer channel |
| Beacon | - |
| BEARER | cf. channel, service |
| BEM | Block Edge Mask |
| Benchmarking | Benchmarking |
| BICC | Bearer-independent call control |
| BIIS | BInary Signalling System for non-trunked PMR |
| B-ISDN | Broadband ISDN |
| B-ISUP | Broadband ISUP |
| bitcoin | - |
| Block Edge Mask | - |
| blockchain | |
| BONDING | (electrical safety connection) |
| bone conduction | - |
| B-QSIG | Broadband QSIG |
| BR | - |
| BROADBAND | (inc. B-ISDN) |
| BROADCAST | point to multipoint message transfer - see "multipoint" |
| BROADCASTING | Broadcasting, TV, audio |
| BSS | Broadcast Satellite Services |
| BSSAP | BSS Application Part (GSM protocol) |
| BSV | - |
| BTA | Backhaul Traffic Availability |
| building | - |
| BWA | Broadband Wireless Access |
| C REFERENCE POINT | C Reference point (ISDN) |
| CA | Conditional Access |
| CABLE | - |
| cables | - |
| CAdES | CMS Advanced Electronic Signature |
| Calculation | |
| CALL BARRING | Call Barring (supplementary service) |
| Call Centre | - |
| CALM | Continuous Air Interface for Long and Medium distance |
| CAMEL | Customized applications for mobile network enhanced logic |
| CAP | Conformance Assessment Process |
| capacity | - |
| CARD | Intelligent Card |
| categorization | - |
| category | - |
| CB | Citizens Band (radio) |
| CB-AdES | - |
| CBC | Cell Broadcast Centre (GSM) |
| CBDS | Connectionless Broadband Data Service |
| CBOR | - |
| CBS | Cell Broadcast Service |
| CCBS | Completion of Call to Busy Subscriber |
| CCM | Container Infrastructure Service (CIS) Cluster Managem |
| CCM system | - |
| CCNL | Completion of Communications on not Logged-in |
| CCNR | Completion of Call on No Reply (supplementary service) |
| CCS | Common Channel Signalling |
| CDA | Call Distribution to Attendant (supplementary service) |
| CDHN | Convergent Digital Home Network |
| CDIV | Call Diversion (supplementary service) |
| CDMA | Code-Division Multiple Access |
| cdma2000 | Code-Division Multiple Access 2000 |
| CDN | Content Delivery Network |
| CELL | (radio) |
| cellular | cellular (radio) |
| CENTREX | - |
| Certificate | - |
| CF | Call Forwarding (supplementary service) |
| CGNAT | - |
| channel bandwidths | - |
| Channel coding | - |
| channel model | - |
| channel modelling | - |
| CHARACTER | Characters, symbols, graphics, pictograms |
| CHARGING | Charging, billing, accounting |
| Chat | - |
| children | cf. Human Factors |
| CHIRPING | - |
| CI Plus | CI Plus |
| CI/CD | Continuous Integration and Continuous Delivery |
| CIRCUIT MODE | - |
| Citizen | - |
| city | - |
| city buildings | - |
| CL | Connectionless, non-connection-oriented |
| CLAT | - |
| Climate change mitigation | Reductions in human emissions of greenhouse gases |
| CLIP | Calling Line Identification Presentation (supp. service) |
| CLIR | Calling Line Identification Restriction (supp. service) |
| closed control loop | - |
| closed loop control | - |
| CLOUD | - |
| Cloud computing | - |
| Cloud Gaming | - |
| cloud-native | |
| CMTS | Cable Modem Termination System |
| CNAP | Calling Name Presentation (supplementary service) |
| CNIP | Calling Name Identification Presentation (supplementary ser) |
| CNIR | Calling Name Identification Restriction (supplementary serv) |
| CO | Call Offer (supplementary service) |
| CO2 emission | - |
| coaxial | - |
| cochlear implant | |
| CODEC | COder/DECoder |
| CODING | - |
| coexistence | |
| Cognition | - |
| cognitive | - |
| COLP | COnnected Line identification Presentation (supp. service) |
| COLR | COnnected Line identification Restriction (supp. service) |
| Commerce | - |
| Communications module | - |
| companion screen | - |
| CONF | Conference (supplementary service) |
| CONFIDENTIALITY | (security) |
| CONFIGURATION | - |
| conflict detection | - |
| CONFORMANCE | Conformance of an equipment to a standard |
| conformity | - |
| Congestion Control | - |
| CONNECTION-ORIENTED | CONNECTION ORIENTED |
| CONNECTOR | - |
| CONP | Connected Name Identification Presentation (supp. service) |
| Container | - |
| Content | - |
| Content Delivery Network | - |
| Context capturing and analysis | |
| CONTRIBUTION | (to TV distribution network) |
| CONTROL | - |
| Control Interface | - |
| Conversation | - |
| cooling capacity | |
| coordination | - |
| COP | Code Of Practice |
| Core Network | - |
| cost impact | - |
| Countermeasures | - |
| COUPLING | (electric, magnetic, acoustic) |
| Covid | - |
| CPE | Customer Premise Equipment |
| C-PMSE | Cognitive Programme Making Special Events |
| CR | Call Restriction (supplementary service) |
| CRA | - |
| Critical Infrastructure | - |
| CROSS CONNECT | - |
| CROSSTALK | (in transmission cables, ...) |
| CRS | Cognitive Radio System |
| CS1 | Capability Set 1 |
| CS2 | Capability Set 2 (IN) |
| CS3 | Capability Set 3 (IN) |
| CS4 | Capability Set 4 (IN) |
| CSFB | - |
| CSMA | Carrier Sense Multiple Access |
| CST | Call Setup Time |
| CSTA | Computer-supported telephony applications |
| CT | Cordless Telephone |
| CT2 | Cordless Telephone - 2nd generation |
| CTAN | Cordless terminal authentication - terminal (supp. svce.) |
| CTAT | Cordless terminal authentication - network (supp. svce.) |
| CTE | Circuit-Terminating Equipment |
| CTM | Cordless Terminal Mobility |
| CTS | Conformance Test Services |
| CTSD | |
| CUG | Closed User Group (supplementary service) |
| Customer Premises Networks | |
| customer service | - |
| CVG | Convergence (layer) |
| CW | Call Waiting (supplementary service) |
| Cyber | - |
| Cyber Security | - |
| Cyber-defence | - |
| Cybersecurity | - |
| D2-MAC | TV (see MAC) |
| DAA | Detect-And-Avoid |
| DAB | Digital Audio Broadcasting |
| DAM | DECT Authentication Module |
| DASH | - |
| DATA | - |
| data base | - |
| Data Centres | - |
| data collection | - |
| data export | - |
| data interoperability | data interoperability |
| data management | - |
| data mechanism | - |
| data models | - |
| data portability | - |
| data preservation | - |
| data processing | - |
| data sharing | - |
| data space | - |
| data storage | - |
| data storage equipment | - |
| data usability | ability of a user to derive useful information from data |
| datasheets | - |
| D-band | - |
| DCE | Data Circuit terminating Equipment |
| D-CHANNEL | ISDN signalling channel |
| DCS | (extension of GSM) |
| DDI | Direct Dialling In (supplementary service) |
| Decentralized Identifier | DID |
| DECT | Digital Enhanced Cordless Telecommunications |
| DECT-2020 | - |
| definitions | - |
| de-jitter buffer | |
| delay | |
| deployement trial | - |
| deployment | - |
| deployment scenarios | - |
| design | - |
| Design for All | cf. Human Factors |
| deterministic latency | - |
| device | - |
| device complexity | - |
| DevOps | Development and Operat |
| DFRS | Digital Fixed Radio Systems |
| Diameter | |
| dictionary | |
| DIGITAL | - |
| digital certificate | - |
| Digital Clone | - |
| digital identity | digital identity |
| Digital Right Management | - |
| digital signature | |
| Digital Twins | - |
| digitalized | - |
| Directive 2014/53/EU | |
| DIRECTORY | - |
| DISABILITY | cf. Human Factors |
| DISCRETE | Discrete listening (supplementary service) |
| DISKETTE | Diskette associated with this item |
| Distortion | - |
| distributed | - |
| distributed filters | |
| Distributed Ledger | - |
| distribution | - |
| Diversity | cf. Human Factors |
| DLC | Data Link Control |
| DMAP | DECT Multimedia Access Profile |
| DMO | Direct mode operation (TETRA) |
| DND | Do Not Disturb (supplementary service) |
| DNS | Domain name system |
| DOCSIS | Data Over Cable Service Interface Specification |
| Double talk | - |
| downlink | - |
| dPMR | digital Private Mobile Radio |
| DPP | Digital Product Passport |
| DPRS | DECT Packet Radio Service |
| DQDB | Distributed Queue, Double Bus |
| DRM | Digital Radio Mondiale |
| DROES | Data Receive Only Earth Stations (satellite) |
| DRRS | Digital Radio Relay System |
| DRX | Discontinuous (radio) reception |
| DSB | Double Side Band |
| DSC | Digital Selective Calling |
| DSLAM | Digital Subscriber Line Access Multiplexer |
| DS-Lite | - |
| DSRC | Dedicated Short Range Communications |
| DSRR | Digital Short Range Radio |
| DSS1 | Digital Subscriber Signalling no. 1 (ISDN) |
| DSS2 | Digital Subscriber Signalling no. 2 (B-ISDN) |
| DTE | Data Terminal Equipment |
| DTH | Direct to the home (satellite broadcasting) |
| DTM | Dynamic synchronous transfer mode (transmission / switching) |
| DTMF | Dual Tone Multi-Frequency (in-band signalling) |
| DTX | Discontinuous (radio) transmission |
| DVB | Digital Video Broadcasting |
| DVB-H | Digital Video Broadcasting Handheld |
| DVB-I | - |
| DVB-SH | |
| dynamic spectrum sharing | - |
| Dynamic Triggering | - |
| EAA | Electronic Attestation of Attributes |
| Earphones | - |
| EARTH STATION | (satellite) |
| EARTHING | - |
| Ear-Worn Devices | - |
| E-band | - |
| ecall | Manual/automatic initiated emerg. call (TS12) from vehicle |
| ECHO | - |
| e-commerce | electronic commerce |
| Ecosystem | - |
| ECT | Explicit Call Transfer (supplementary service) |
| e-delivery services | - |
| EDGE | Enhanced Data Rates for GSM Evolution |
| EEER | Equipment Energy Efficiency Ratio |
| eHealth | |
| EHF | Extremely High Frequency (30 GHz to 300 GHz) |
| E-INTERFACE | (GSM) |
| ELECTRIC | - |
| electro-acoustic | - |
| electronic preservation | - |
| electronic registered delivery | - |
| ELECTRONIC SIGNATURE | - |
| embedded | |
| EMC | Electro-Magnetic Compatibility |
| EMERGENCY | Including maritime/terrestrial search & rescue |
| emergency communications | |
| emergency services | - |
| EMF | electromagnetic field (cf safety) |
| EMISSION | Of unwanted signals, radiated/conducted (EMC) |
| eMLPP | enhanced Multi-Level Precedence and Pre-emption service |
| e-mobility | - |
| E-Model | (speech quality) |
| encryption | |
| ENDORSEMENT | Endorsement of a Standard/Recommendation from another body |
| End-user | - |
| energy consumption | - |
| Energy Efficiency | - |
| Energy Management | - |
| enforcement | |
| ENG | Electronic News Gathering (satellite) |
| Enhanced Mobile Broadband | - |
| enum | mapping E.164 numbers to URI (universal resource identifier) |
| ENv | ETSI deliverable - as a basis for CEN/CENELEC ENv |
| ENVIRONMENT | - |
| Environmental impact | - |
| environmental information | - |
| EPC | Evolved Packet Core |
| EPG | Electronic Programme Guide |
| EPIRB | Emergency Position Indicating Radio Beacons |
| EQUIPMENT PRACTICE | - |
| ERDS | Electronic Registered Delivery Service |
| ER-GSM | |
| ERMES | European Radio MEssaging System |
| ERROR HANDLING | - |
| ERS | - |
| eSSP | embedded Smart Secure Platform |
| ESV | Earth Station on board Vessel |
| ethernet | - |
| ethics | - |
| ETSI meetings | - |
| EU qualified | - |
| EUDI Wallet | EU Digital Identity Wallet |
| E-UTRA | Enhanced-UMTS Terrestrial Radio Access |
| EV | Electric Vehicle |
| Evaluation | - |
| EVOLUTION | - |
| eWarrant | - |
| e-waste management | - |
| Exposure | - |
| extended validation certificat | extended validation certificate |
| F5G | - |
| F5G Advanced | - |
| FACILITY | - |
| FAX | Facsimile |
| FDD | Frequency Division Duplexing |
| FDMA | Frequency Division Multiple Access |
| FEATURE KEY | (ISDN generic protocol) |
| FEC | Forward Error Correction |
| FIBRE | (optical) |
| Field trial | - |
| filtering | |
| firewall | |
| Fixed networks | - |
| flexible deployment | - |
| Flexilink | - |
| FM | Frequency Modulation |
| FMBS | Frame Mode Bearer Service |
| FOLLOW ME | Follow me supplementary service |
| Food | - |
| FPH | Free-Phone (supplementary service) |
| FPLMTS | Future Public Land Mobile Telecommunications System |
| FRAME MODE | - |
| FRAME RELAY | - |
| Framework | - |
| frequency range | - |
| FRMCS | Future Rail Mobile Communication System |
| Front haul | - |
| fronthaul | - |
| FS | Fixed Services |
| FSS | Fixed Satellite Services |
| FT | File Transfer |
| FTS | Fixed Terminal Subsystem |
| FTTR | Fibre To The Room |
| Full-Band | - |
| FUNCTIONAL | (ISDN generic protocol) |
| functional architecture | - |
| functional block | - |
| future releases | |
| FWA | Fixed Wireless Access (cf RLL, WLL, FRA) |
| FWS | Fixed Wireless Systems |
| GAP | Generic Access Profile (DECT) |
| gap analysis | |
| GATEKEEPER | - |
| GATEWAY | - |
| GEM | - |
| GEM 1.3 | - |
| GenAI | Generative AI |
| gender-balanced design | - |
| GENERIC | - |
| GFT | Graphical presentation Format (TTCN-3) |
| GLDB | Geo Location DataBase |
| GMDSS | Global Maritime Distress and Safety System |
| GMPRS | GEO (Geostationary Earth Orbit) Mobile Packet Radio Service |
| GMR | GEO (Geostationary Earth Orbit) Mobile Radio |
| GMR-1 | GEO (Geostationary Earth Orbit) Mobile Radio - family 1 |
| GMR-2 | GEO (Geostationary Earth Orbit) Mobile Radio - family 2 |
| GNSS | Global Navigation Satellite System |
| GPRS | General Packet Radio Service |
| graphical notation | - |
| green-house gas emission | - |
| GRIDS | GeneRic ID Services |
| GROUP 3 | (facsimile) |
| GROUP 4 | (facsimile) |
| group call | |
| GROUP NUMBER | Dynamic Grp No Assignement (supplementary service) |
| GSM | Global System for Mobile communications |
| GSM_PHASE1 | GSM Phase 1 |
| GSM_PHASE2 | GSM Phase 2 |
| GSM_PHASE2_PLUS | GSM Phase 2+ |
| GSM-R | GSM for Railways |
| GSO | Geostationary Satellite Orbit |
| GTP | GPRS Tunnelling Protocol |
| GTPv2-C | GPRS Tunnelling Protocol Version 2 - Control Plane |
| H.248 | ITU-T recommendation |
| H.323 | ITU-T recommendation |
| H.F. | High Frequency (3 MHz to 30 MHz) |
| HANDBOOK | - |
| handheld microphone | - |
| HANDOVER | (between cells, between networks) |
| handset | - |
| HANDSFREE | (voice terminal operation) |
| HAPS | High Altitude Platform Station |
| Harmonised standard | - |
| HDMAC | High Definition MAC |
| HDR | High Dynamic Range |
| HDR Composer | - |
| HDR Metadata Embedder | - |
| HDSL | High bit rate Digital Subscriber Line |
| HDTV | High Definition TV |
| Headphones | - |
| headset | - |
| HEALTH | Long term health aspects under RTTE directive. See SAFETY. |
| HEARING AID | - |
| Hearing Impairment | - |
| Hearing Loop System | - |
| HEO | Highly-inclined Elliptical Orbit (satellite) |
| HF | Human Factors |
| HFC | Hybrid Fibre Coaxial |
| hidden node | cf. Powerline |
| HIPERACCESS | high speed fixed radio access to customer premises |
| HIPERLAN | HIgh PErformance Radio Local Area Networks (LAN) |
| HIPERMAN | High performance radio metropolitain area networks |
| HLC | High Layer Capability information element (ISDN) |
| HOLD | (service) |
| Home Gateway | - |
| HomePlug AV | - |
| HTML | HyperText Mark-up Language |
| human voice communication | - |
| HYBRID | Mixed analogue/digital; or fibre/copper medium |
| Hybrid Cabling System | - |
| IBCF | Interconnection Border Control Function |
| ICO | Intermediate Circular Orbit |
| ICONS | cf. Human Factors |
| ICS | Implementation Conformance Statement |
| ICT | Information and Communications Technology |
| ICT site hosting | - |
| ICT sites | - |
| ID | Identification, Identity |
| identification | identification |
| Identity | - |
| Identity proofing | - |
| IDL | Interface Description Language |
| IE | Information Element (ISDN signalling) |
| IEM | In-Ear Monitor |
| IFDN | Indoor Fibre Distribution Network |
| IIoT | Industrial Internet of Thing |
| IM | Intent Management |
| IM service interface | |
| IMB | - |
| IMEI | International MS Equipment Identity (GSM) |
| immersive | |
| IMMUNITY | ... to radiated/conducted interference (EMC) |
| impairment | - |
| Implant | - |
| IMS | IP Multimedia System |
| IMT | International Mobile Telecommunications |
| IMT-2000 | International Mobile Telecommunications 2000 (ITU project) |
| IMT-2020 | - |
| IMT-Advanced | IMT-Advanced |
| IN | Intelligent Network |
| INAP | IN Application Protocol |
| INBAND | In band (signalling) |
| INCLUDE | Include Call (supplementary service) |
| inclusive design | - |
| incumbent | - |
| inductive | - |
| Industrial | - |
| Industry | - |
| Information assurance | - |
| INFORMATION MODEL | Information model (see X.720) |
| information preservation | |
| instrumental | |
| INT | call INTrusion (supplementary service) |
| Intelligence-defined Network | - |
| intelligent homes & buildings | - |
| intelligent mobility | - |
| intelligent transportation | - |
| Intelligibility | - |
| intent management | - |
| INTERACTION | (between services) |
| Interception | - |
| interconnection | - |
| INTERFACE | - |
| Interference Analysis | - |
| INTERNET | - |
| INTEROPERABILITY | between equipment from different suppliers |
| inter-system | - |
| INTERWORKING | (between networks, between equipment in general) |
| intra-system | - |
| ION | Identity Oriented Networks |
| IoT | Internet of Things |
| IoT platforms | |
| IP | Internet Protocol |
| IP address | - |
| IP Address Resolution | - |
| IP Retention | - |
| IPCable | IP services in cable TV networks |
| IP-Network | - |
| IPR | Intellectual Property Right |
| IPTV | Internet Protocol TeleVision |
| IPv4 | - |
| IPv6 | Internet Protocol version 6 |
| ISAC | Integrated Sensing And Communications |
| ISDN | Integrated Services Digital Network |
| ISM | Industrial, Scientific and Medical radio band (433 MHz) |
| Isolation | - |
| ISPBX | Integrated Services Private Branch Exchange |
| iSSP | integrated SSP |
| IST | Immediate Service Termination |
| ISUP | ISDN User Part (of SS7) |
| ITS | Intelligent Transport Systems |
| IXIT | Implementation, eXtra Information for Testing |
| jitter buffer | |
| JSON | - |
| KEY ESCROW | (security) |
| Key Exchange | - |
| KEYPAD | (generic ISDN protocol) |
| keyword | - |
| Knowledge Graph | |
| knowledge management | - |
| Knowledge-based Reasoning | |
| Knowledge-Enhanced | - |
| KPI | KPI Performance Indicator |
| L2VPN | - |
| LAN | Local Area Network |
| Language | - |
| LAPB | Link Access Protocol, Balanced (packet signalling) |
| LAPD | Link Access Protocol, D-channel (ISDN) |
| large antenna array | - |
| large language model | |
| LASER | - |
| LATE ENTRY | Late entry (supplementary service) |
| Lawful Disclosure | - |
| Lawful Interception | Lawful Interception |
| LAYER 1 | (of OSI 7-layer model) |
| LAYER 2 | (of OSI 7-layer model) |
| LAYER 3 | (of OSI 7-layer model) |
| LAYER 4 | (of OSI 7-layer model) |
| LAYER 6 | (of OSI 7-layer model) |
| LAYER 7 | (of OSI 7-layer model) |
| LBRDC | Low Bit Rate Data Communications |
| LC | LSA Controller |
| LC3plus | Low Complexity Communication Codec plus |
| LCA | Life Cycle Assessment |
| LE | Local Exchange |
| LEASED LINE | - |
| ledger | |
| LEO | Low Earth Orbiting Satellite |
| levels | - |
| LF | Low Frequency (30 kHz to 300 kHz) |
| LH | Line Hunting (supplementary service) |
| License schemes | - |
| Lightweight Certificate Policy | - |
| LIST | List search call (supplementary service) |
| Listen Before Talk | - |
| listening effort | - |
| listening quality | - |
| LLC | Low Layer Compatibility information element (ISDN) |
| LLM | Large Laguage Model |
| LMES | Land Mobile Earth Station (satellite) |
| LMSS | Land Mobile Satellite Services |
| LNB | Low Noise Block |
| local | - |
| LOCAL LOOP | (copper, fibre, radio, ...) |
| localisation | |
| LOCATION | Location |
| location information | |
| lossless | - |
| LOUDNESS | (rating) |
| LOUDSPEAKING | (voice terminal) |
| low latency | - |
| low power | - |
| LOWER LAYER | (of OSI 7-layer model) |
| LPR | Level Probing Radar |
| LR | LSA Repository |
| LSA | Licensed Shared Access |
| LSA spectrum resource | |
| LSE | Logical Secure Element |
| LSI | Logical Secure element Interface |
| LSN | Large Scale NAT |
| LTE | (LTE: 3GPP technology beyond UMTS/HSPA+) |
| LTE-Advanced | LTE-Advanced |
| LTN | Low Throughput Networks |
| M2CNP | - |
| M2M | Machine to Machine (Communication) |
| M2PA | Message Transfer Part 2 User Peer-to-Peer Adaptation Layer |
| M2UA | MTP2 user adaptation |
| M3UA | MTP3 user adaptation |
| MaaS | Model-as-a-Service |
| MABR | - |
| MAC | Multiplex Analogue Components or Medium Access Control |
| MAGNETIC | (coupling) |
| MAINTENANCE | Maintenance |
| MAN | Metropolitan Area Network |
| MAN-Advanced | MAN-Advanced |
| MANAGEMENT | Management |
| Management Plane | - |
| Mandates | - |
| MANO | Management and Orchestration |
| Manufacturing | - |
| MAP | Mobile Access Protocol |
| mapping system | - |
| MARITIME | (Cf terrestrial, satellite, aeronautical) |
| market placement | - |
| Match percentage | |
| maturity assessment | - |
| MBSFN | - |
| MBT | Model Based Testing |
| MCBTS | Multi Carrier Base Tranceiver Station |
| MCID | Malicious Call Identification (supplementary service) |
| MCOBA | |
| M-Commerce | Mobile Commerce |
| MDAF | Management Data Analytics Function |
| Measurement | - |
| MEASUREMENT UNCERTAINTY | measurement uncertainties |
| MEC | Multi-Access Edge Computing |
| MEGACO | Media Gateway Controller |
| MEO | Medium Earth Orbit (satellite) |
| MES | Mobile Earth Station (satellite) |
| META-PROTOCOL | - |
| METASIGNALLING | - |
| metaverse | - |
| METHODOLOGY | - |
| metrics | |
| MF | Medium Frequency (300 kHz to 3 MHz) |
| MFCN | Mobile/Fixed Communication Network |
| MFF | Machine to machine Form Factor |
| MGC | Media Gateway Controller |
| MHEG | Multimedia/Hypermedia Experts Group |
| MHI | Message Handler Interface |
| MHP | - |
| MHS | Message Handling System |
| MICROCOMPUTER | - |
| microwave | - |
| midhaul | - |
| MIGRATION | - |
| Millimetre wave | - |
| MIMO | Multiple Input Multiple Output |
| MIMs | Minimal Interoperability Mechanisms |
| mission critical applications | - |
| mission critical communication | - |
| ML | Machine Learning |
| ML watermarking | Machine Learning watermarking |
| MMC | Meet Me Conference (supplementary service) |
| MME | Mobility Management Entity |
| MMI | Man-Machine Interface, human factors |
| MMS | Multimedia Messaging Service |
| MMSS | Maritime Mobile Satellite Service |
| MO | Managed Object |
| MOBILE | (telecommunications in general) |
| MOBILITY | (concept of) |
| mobility support | - |
| MOCS | Managed Object Conformance Statement |
| Model | - |
| model-driven engineering | - |
| modelling | |
| MODEM | MOdulator/DEModulator |
| MODULATION | - |
| Module | |
| MONOMODE | Optical fibre; terminal equipment |
| MOS | Mean Opinion Score |
| MPA | Multi-PTN Attendant (supplementary service) |
| MPEG | Motion Picture Experts Group |
| MPLS | Multi Protocol Label Switching |
| MPTY | Multiparty (supplementary service) |
| MPX | Multiplex(er) |
| MRVT | MTP Routeing verification test |
| MS | Mobile (radio) Station |
| MS-Aloha | Mobile Slotted Aloha |
| MSAN | Multi-Service Access Node |
| MSAP | Mobile Service Access Point |
| MSC | Mobile system Switching Centre |
| MSN | Multiple Subscriber Number (supplementary service) |
| MSR | Multi Standard Radio |
| MSS | Mobile Satellite Service |
| MTA | Message Transfer Agent |
| MTP | Message Transfer Part (SS7) |
| MTP2 | Message Transfer Part layer 2 |
| MTP3 | Message Transfer Part layer 3 |
| MTS | Message Transfer System |
| multi service testing | - |
| MULTICALL | supplementary service; <1 cct-switched call per UE |
| MULTICHANNEL | Multiple 64 kbit/s channels |
| MULTIMEDIA | inc Hypermedia |
| MULTIMODE | Optical fibre; terminal equipment |
| multi-party computation | - |
| multi-path | Transmission from multiple sources to each destination |
| MULTIPOINT | multipoint to multipoint communication - see "broadcast" |
| multi-source | Transmission from multiple sources to each destination |
| MU-MIMO | - |
| MUX | Multiplex, multiplexing |
| MWI | Message Waiting Indication (supplementary service) |
| MWS | Multimedia Wireless Systems |
| mWT | millimetre wave, transmission |
| NAME | (generic identification supplementary services) |
| narrowband | - |
| NAT | - |
| NAT64 | - |
| Native AI | |
| NAVIGATION | cf. Human Factors |
| NAVTEX | Navigation telegraph |
| NBI | Northbound Interface |
| NCF | Network Control Facilities |
| NE | Network Element |
| near-field | - |
| NETWORK | - |
| network coding | Operation on Source Symbols that produces Coded Symbols for |
| Network KQI | - |
| Network Large Language Model | - |
| network large mode | - |
| network large model | - |
| network management | - |
| Network Measurement | - |
| Network monitoring | - |
| Network Performance | - |
| Network scenarios | - |
| new functionality | |
| new KPIs | |
| Next Generation Protocol | - |
| NFC | Near Field Communication |
| NFV | Network Functions Virtualization |
| NFV evolution | |
| NFVI | NFV Infrastructure |
| NFVO | Network Functions Virtualisation Orchestrator |
| NGAP | NG Application Protocol |
| NGSI-LD | - |
| NICAM | Near-instantaneous companded audio multiplex |
| NINT | Network Interception (supplementary service) |
| NIT | Network Integration Testing |
| NMDS | Narrowband Multi-service Delivery System |
| NNI | Network-Network Interface |
| NOISE | - |
| Noise Cancellation | - |
| NOMADIC | Nomadic Wireless Access |
| non 3GPP access | - |
| NON-GSO | Non-GeoStationary Orbit |
| Normalized Certificate Policy | - |
| NP | Number Portablilty |
| NR | 3GPP 5G radio access technology |
| NS | Night Service (supplementary service) |
| NSS | Network Switching Subsystem |
| OAM | Operations And Maintenance |
| OAN | Optical Access Network |
| object audio | - |
| OBJECT IDENTIFIER | (ASN.1) |
| objective | |
| ODA | Open Document Architecture |
| OFDM | Orthogonal Frequency-Division Multiplexing |
| OFDMA | Orthogonal Frequency-Division Multiple Access |
| Offloading | - |
| OIP | Originating Identification Presentation |
| OIR | Originating Identification Restriction |
| OJEU | |
| OKPI | Operational Key Performance Indicators |
| OLT | Optical Line Terminal |
| OMAP | Operations, Maintenance and Administration Protocol |
| ON | Optical Distribution Network |
| oneM2M | - |
| ONP | Open Network Provision |
| ontology | ontology |
| open source | |
| Open Source Software | OSS |
| operation | |
| operational | - |
| OPTICAL | (fibre) |
| Optical Access Network | - |
| Optical Network Device | - |
| O-RAN | |
| orchestration | |
| OSA | Open Service Access |
| OSI | Open Systems Interconnection |
| OSS | Open Source Software |
| OSSS | Orthogonal Sequence Spread Spectrum |
| OTE | Open Testing Environment |
| OTT voice applications | OTT voice applications |
| OTT voice generic clients | OTT voice generic clients |
| OUTBAND | Out of band (signalling) |
| outdoor enclosure | |
| PABX | Private Automatic Branch Exchange |
| PACKET MODE | - |
| PAD | Packet Assembler/Disassembler |
| PAdES | PDF Advanced Electronic Signature |
| PAGING | - |
| Pandemic | - |
| PAP | Public Access Profile |
| parallel task | - |
| parametrization | - |
| PAS | Publicly Available Specification |
| PAT | - |
| PATH | - |
| PATH REPLACEMENT | (ANF) |
| Payment | - |
| PAYPHONE | - |
| PCI | Programmable Communications Interface |
| PCM | Pulse Code Modulation |
| PCN | Personal Communications Network |
| PCTR | Protocol Conformance Testing Report |
| PDC | Programme Delivery Control (for domestic video/VCR) |
| PDH | Plesiochronous Digital Hierarchy |
| PDL | Permissioned Distributed Ledger |
| PDN | Public Data Network |
| PDO | Packet data optimized (TETRA) |
| PERFORMANCE | (inc. Quality of Service) |
| personalization | adaptation to personal preferences and needs |
| PES | PSTN/ISDN Emulation Subsystem |
| PHI | Packet Handler Interface |
| PHOTOGRAPHIC | (syntax) |
| Physical layer | - |
| PICS | Protocol Implementation Conformance Statement |
| PICTOGRAMS | cf. Human Factors |
| PIM | Physical Infrastructure Management |
| PINX | PTN Exchange |
| PISN | Private Telecommunication Network |
| PIXIT | Protocol Implementation, eXtra Information for Testing |
| PLANNING | - |
| plastic | - |
| PLAT | - |
| Platforms | - |
| PLCP | Physical Layer Convergence Procedure |
| PLMN | Public Land Mobile Network |
| PLUS | to cover for + as in Phase 2+ |
| PMBS | Packet Mode Bearer Service |
| PMR | Private Mobile Radio |
| PMSE | Programme Making Special Events |
| POF | Plastic Optical Fiber |
| POINT-TO-MULTIPOINT | - |
| POINT-TO-POINT | |
| policies | - |
| policy management | - |
| policy requirements | - |
| PON | Passive Optical Network |
| PORTABILITY | - |
| post-quantum cryptography | - |
| POTS | Plain Old Telephone Service |
| POWER | (radio transmission) |
| Power Measurement | - |
| Power over Coaxial Cable | - |
| POWER SUPPLY | - |
| powering | - |
| Powerline | - |
| pre-connectorized | - |
| prediction | |
| PRIMARY | (rate, ISDN access) |
| PRIORITY CALL | Priority Call (supplementary service) |
| privacy | - |
| PRIVATE | (network) |
| PRM | Premium Rate service |
| PROCEDURE | - |
| procurement | - |
| product | - |
| product details | - |
| PROFILE | (protocol stack) |
| profile overview | |
| Proof of Concept | |
| propagation | - |
| PROTECTION | ...against transients, EMC, etc |
| PROTOCOL | - |
| Provenance | - |
| Provider | - |
| PSAP | Public Safety Answering Point |
| PSPDN | Packet Switched Public Data Network |
| PSS1 | Private network Q reference point Signalling System number 1 |
| PSTN | Public Switched Telephone Network |
| PTS | Profile Test Specification |
| PUBLIC | (network) |
| Public key | Public key (encryption) |
| Public Safety | - |
| PUM | Private User Mobility |
| push | Push service (unsolicited information transfer to user) |
| PVC | Permanent Virtual Call |
| PWS | Public Warning System |
| PWSN | People With Special Needs |
| Q3 INTERFACE | - |
| QERDS | Qualified Electronic Registered Delivery Service |
| QoE | Quality of Experience |
| QoE layered model | - |
| QoS | Quality of Service |
| QREM | Qualified Registered Electronic Mail |
| QSIG | PTN signalling at the Q reference point |
| QUALITY | - |
| quantum cryptography | |
| Quantum Key Distribution | |
| Quantum Safe Cryptography | - |
| quick ODN | - |
| R2 | Signalling system R2 |
| RACK | - |
| RADAR | - |
| RADIO | - |
| radio interface | |
| radio measurements | |
| RADIO MIC | Wireless microphone |
| radio parameters | - |
| Radio Resource Management | - |
| radiodetermination | - |
| railways | - |
| RAN | - |
| RAN architecture | - |
| RAP | Radio Application Package |
| RATE | (transmission bit rate) |
| RC | Remote Control (supplementary service) |
| RCS | Rich Communication Suite |
| RDS | Radio Data System |
| RDSS | Radio Determination Satellite Service |
| real time | real time |
| Real World capture | - |
| Real-time text | - |
| RECEIVER | (radio, etc) |
| RED | - |
| Referential specification | - |
| registered e-delivery services | - |
| registered electronic mail | - |
| REGISTRATION | (see also ADMINISTRATION) |
| REGULATION | Signifies relevance to EC Directive. |
| RELAY | Radio relay |
| relay services | |
| release | - |
| RELIABILITY | |
| REM | Registered Electronic Mail |
| REMOTE | (control, surveillance, etc) |
| remote resources access | - |
| remote services access | - |
| renewable | - |
| REPEATER | (radio) |
| REPLICATION | of directories, etc |
| REPORT | Call report (supplementary service) |
| Request For Proposal (RFP) | |
| Requirements | - |
| RES | Radio Equipment and Systems |
| residential network | - |
| resilience | |
| resiliency | |
| Retained Data | - |
| RETENTION | Call retention (supplementary service) |
| RETRIEVAL | document, database, etc |
| REV | Reverse charging |
| Reverberation | - |
| reverse | - |
| RF HW models | - |
| RF/analog impairments | - |
| RFID | - |
| R-GSM | |
| RINA | - |
| RIS | Reconfigurable Intelligent Surfaces |
| risk | |
| risk assessment | - |
| risk management | - |
| RLAN | Radio Local Area Network |
| RLL | Radio in the Local Loop |
| RLP | Radio Link Protocol (GSM) |
| RNIS | |
| RO | Receive Only |
| ROAMING | (mobile) |
| ROBUSTNESS | |
| router | |
| routing support | - |
| RPF | Reverse Power Feed |
| RRS | Reconfigurable Radio System |
| RTP | - |
| RTTH | Radio To The Home (DECT) |
| RTTT | Radio Transport and Traffic Telematics |
| Runtime | |
| S REFERENCE POINT | S Reference Point |
| S/MIME | - |
| S11 | interface between the MME and S-GW |
| S1AP | S1 Application Protocol |
| SAFETY | - |
| SAR | Search And Rescue |
| SAREF | - |
| SARS-CoV-2 | - |
| SATELLITE | (Cf terrestrial, aeronautical, maritime) |
| SBA | Service Based Architecture |
| SBI | SouthBound Interface |
| SC | Service Centre (GSM) |
| scalability | - |
| SCAS | Security Assurance Spec |
| SCCP | Signalling Connection Control Part (SS7) |
| scenarios | - |
| scene | |
| SCF | Selective Call Forwarding supplementary service |
| SCFB | SCF on Busy supplementary service |
| SCFNR | SCF on No Reply supplementary service |
| SCFU | SCF Unconditional supplementary service |
| SCHEDULING | - |
| SCL | SSP Common Layer |
| scoring | - |
| SCR | Screening (supplementary service) |
| SCRIPT | programme, sequence of commands |
| SCS | System Conformance Statement |
| SCTP | Simple Control Transmission Protocol (IETF) |
| SCWS | Smart Card Web Server |
| SDH | Synchronous Digital Hierarchy |
| SDL | Specification and Description Language |
| SDN | Software Defined Networks |
| SDR | Software Defined Radio |
| SDS | Short Data Service |
| SDSL | Symetrical / Short range Digital Subscriber Line |
| SE | Serial Call (supplementary service) |
| SECTION | (view across interface) |
| secure by default | |
| secure element | - |
| secure e-mail | - |
| SECURITY | - |
| Security by default | - |
| Security Management | - |
| Security mode | (Mobile Commerce) |
| Security requirements | - |
| SELCALL | Selective Calling (radio) |
| Self-Management | - |
| self-organization | |
| Self-organizing | - |
| Semantic | Semantic |
| semantic reasoning | - |
| Sensor | - |
| server | - |
| SERVICE | - |
| service classification | - |
| service KQI | - |
| service model | - |
| Session Initiation Protocol | SIP |
| SFC | Service Function Chain |
| SG | Signalling Gateway |
| SGW | Serving Gateway |
| sharing | - |
| SHF | Super High Frequency (3 GHz to 30 GHz) |
| SHORT NUMBER | Short number addressing |
| SHORT RANGE | (radio) |
| sign language | |
| SIGNAL PROCESSING | SIGNAL PROCESSIng |
| SIGNALLING | |
| SIGTRAN | Signalling transport (IETF WG) |
| SIM | Subscriber Identity Module (GSM) |
| Simulation | - |
| SIP | Supplementary Information Presentation (supp. service) |
| SIP-I | Session Initiation Protocol with encapsulated ISUP |
| SITE ENGINEERING | - |
| SLA | Service Level Agreement |
| Slicing | - |
| SLO | Service Level Objectives |
| smart agriculture | - |
| Smart Appliance | - |
| SMART CARD | embedded IC card |
| Smart Cities | - |
| smart city | |
| smart contract | |
| Smart Escalator | |
| Smart Grid | - |
| Smart Identity | - |
| smart industry | - |
| Smart Interface | - |
| Smart Lift | - |
| smart manufacturing | - |
| smart meter | smart meter |
| Smart Voice-Controlled Device | - |
| smart water | - |
| Smart Watering | - |
| smartphone | - |
| SMATV | System Master Antenna TV |
| SME | Small and Medium-sized Enterprise |
| SMS | Short Message Service (GSM) |
| SMSCB | SMS Cell Broadcast |
| SMT | Surface Mount Technique |
| SN | Service Node |
| SNG | Satellite News Gathering |
| software | |
| Software Reconfiguration | - |
| Software-Defined Networking | - |
| SOHO | Small Office Home Office |
| SoLSA | Support of Localised Service Area (SoLSA) (GSM) |
| sound | sound |
| sound field | |
| Southbound Interface | - |
| SPACING | (between radio transmitters) |
| S-PCN | Satellite - Personal Communications Network (Cf PCN) |
| SPECIAL NEEDS | cf. Human Factors |
| Spectral Management | - |
| spectrum | - |
| spectrum regulation | - |
| SPEECH | - |
| SPI | Serial Peripheral Interf |
| Splitter | Device for separation of signals |
| SPREAD SPECTRUM | (radio transmission) |
| SRD | Short Range Device (radio) |
| SRDOC | System Reference Document |
| SS7 | CCITT Common Channel Signalling System No. 7 |
| SSB | Single Side Band modulation |
| SSCF | Service Specific Co-ordination Function |
| SSCOP | Service Specific Connection Oriented Protocol |
| SS-CT | Call transfer (supplementary service) |
| SSF | Service Switching Function |
| SSIG | Terminal-Network signalling at the S reference point |
| SSL/TLS certificates | - |
| SSP | Smart Secure Platform |
| STAGE 1 | (of three stage method) |
| STAGE 2 | (of three stage method) |
| STAGE 3 | (of three stage method) |
| Stakeholders | |
| standardization impacts | - |
| standards framework | - |
| standards landscape | - |
| state of the art | |
| STDMA | Self-Organizing Time Division Multiple Access |
| stereoscopic | - |
| STM | Synchronous Transport Module |
| storage | - |
| STORE | store and forward, stored speech services |
| structure-borne | - |
| SUA | SCCP-user adaptation layer (IETF) |
| SUB | Subaddressing (supplementary service) |
| subjective testing | - |
| SUBSCRIBER | - |
| subtitle | - |
| Superwideband | - |
| SUPPLEMENTARY SERVICE | Supplementary service (also supp. service or ss.) |
| survey | |
| Sustainability | - |
| SWAPPING | - |
| switch | |
| SWITCHING | - |
| SYMBOLS | cf. Human Factors |
| SYNCHRONIZATION | - |
| SYSTEM | - |
| system architecture | - |
| T REFERENCE POINT | T Reference point |
| TAA1 | TETRA Authentication Algorithm number 1. |
| TAA2 | TETRA Authentication Algorithm number 2 |
| TACTILE | MMI for the blind |
| Takedown requests | - |
| TAXONOMY | Taxonomy |
| TC | Transaction Capabilities |
| TCAP | Transaction Capabilities Application Part (SS7) |
| TCI | TTCN-3 Control Interface |
| TCL | Test Case Library |
| TCP-based video services | - |
| TD-CDMA | Time Division - Code-Division Multiple Access |
| TDD | Time Division Duplexing |
| TDL | - |
| TDM | Time Division Multiplex |
| TDMA | Time Division Multiple Access (radio) |
| technical solution | - |
| technological challenge | - |
| Telco Cloud | - |
| Telco-cloud DAS | Telco-cloud data analytics service |
| TELEACTION | ISDN teleservice |
| TELECOMMAND | inc. remote control |
| TELEMETRY | - |
| TELEPHONY | - |
| TELESERVICE | - |
| TELETEX | - |
| TELETEXT | - |
| television products | - |
| Television receivers | - |
| TELEX | - |
| Tenancy | - |
| TERMINAL | (as opposed to NETWORK) |
| terminology | - |
| terms | - |
| TERRESTRIAL | (Cf satellite, maritime, aeronautical) |
| TES | Transportable Earth Station (satellite) |
| test | - |
| Test Tool Interface | - |
| TESTING | - |
| TETRA | TErrestrial Trunked RAdio system |
| TETRAPOL | TETRA - Police (FDMA-PMR) |
| TEXT | - |
| TFI | Terminal Facility Identifier |
| TFT | Tabular presentation Format (TTCN-3) |
| TFTS | Terrestrial-Flight Telecommunications System |
| TH | Trunk Hunting (supplementary service) |
| thermal | |
| Threat Analysis | - |
| threat intelligence | |
| THz | TeraHertz |
| THz component technologies | - |
| THz materials | - |
| time series | time series |
| Timeslicing | - |
| Time-stamping | (security) |
| TIP | Terminating Identification Presentation |
| TIR | Terminating Identification Restriction |
| TMN | Telecommunications Management Network |
| TONE | Information tones on voice terminals/network |
| Total conversation | - |
| TP | Terminal Portability (supplementary service) |
| TPID | Talking party identification (supplementary service) |
| Traceability | - |
| TRAFFIC | - |
| Train | |
| transaction logs | - |
| transceiver efficiency | - |
| transcoding | |
| transducer | - |
| transformer | |
| TRANSIENT | ... voltage, current, field, etc |
| transition | - |
| TRANSMISSION | - |
| TRANSMITTER | (radio) |
| TRANSPONDER | (satellite) |
| TRANSPORT | - |
| TRI | TTCN-3 Runtime Interface |
| TRUNKING | (PMR) |
| trust | |
| trust services | (security) |
| trustworthiness | |
| Trustworthy AI | - |
| TSP1 | Test Synchronisation Protocol no. 1 |
| TSS&TP | Test suite structure & test purposes |
| TTCN | Tree and Tabular Combined Notation |
| TTCN-3 | |
| TTP | Trusted Third Party |
| Tunnelling | - |
| TUP | Telephone User Part |
| TV | TeleVision |
| TVRO | TV Receive Only (satellite earth station) |
| U REFERENCE POINT | U reference point |
| UAN | Universal Access Number service |
| UCI | Universal Communications Identifier |
| UE Identity | - |
| UHDTV | Ultra High Definition TV |
| UHF | Ultra-High Frequency (300 MHz to 3 GHz) |
| UIC | Union Internationale des Chemins de fer |
| UICC | Universal Integrated Circuit Card |
| UIS | User Information System |
| UMB | Ultra Mobile Broadband |
| UML | Universal modelling language |
| UMTS | Universal Mobile Telecommunications System |
| UNB | Ultra Narrow Band |
| Unbundling | Unbundling in the local loop |
| UNDERGROUND | (environment) |
| UNDERWATER | (cabling) |
| UNI | User-Network Interface |
| UPnP | Universal Plug and Play |
| upper layer | |
| UPS | Uninterruptible Power Supply |
| UPT | Universal Personal Telecommunications |
| UR | User Requirements |
| URI | Uniform Resource Identifier |
| usability | extent to which a product can be used |
| usage needs | - |
| USB | Universal Serial Bus |
| USBS | User Signalling Bearer Service |
| use case | use case |
| use cases | - |
| USER | (as opposed to Network) |
| User-Centric | - |
| USSD | Unstructured Supplementary Service Data |
| UTRA | UMTS Terrestrial Radio Access |
| UUS | User-User Signalling (supplementary service) |
| UWB | Ultra Wide Band |
| UWC 136 | Universal Wireless Communication (wrt TIA/EIA 136) |
| V INTERFACE | Interface from AN to LE (see Q.500) |
| V+D | Voice plus data (TETRA) |
| V2X | - |
| V5 INTERFACE | (see V INTERFACE) |
| VAD | Voice Activity Detection |
| VALIDATION | Of functional requirements, such as protocols, etc. |
| VB5 INTERFACE | Broadband interface from AN to SN |
| V-band | - |
| VC | Virtual Call |
| VCC | Virtual Card Calling service |
| VCR | Video Cassette Recorder |
| VDSL | Very high speed Digital Subscriber Line |
| VDSL1 | |
| VDSL2 | |
| VEMMI | Videotex Enhanced MMI (see Videotex, MMI) |
| Verifiable Registry | - |
| VHE | Virtual Home Environment |
| VHF | Very High Frequency (30 MHz to 300 MHz) |
| VIDEO | - |
| Video Security | - |
| Video Surveillance | - |
| VIDEOTEX | - |
| ViLTE | Video over LTE |
| VIM | Virtualised Infrastructure Manager |
| ViNR | Video over New Radio |
| virtual services | |
| Virtualisation | Virtualisation |
| virtualization | |
| VLF | Very Low Frequency (3 kHz to 30 kHz) |
| VM | Virtual Machine |
| VNF | Virtual Network Function |
| Vo5G | Voice over 5G |
| VOCABULARY | Vocabulary, jargon, technical terms, etc |
| VoDSL | Voice over DSL |
| VOICE | Voice band (300 Hz to 3,4 kHz) (Cf SPEECH) |
| VoIP | Voice over Internet Protocol |
| VoLTE | - |
| VoNR | Voice over New Radio |
| VOT | Tele-Voting service |
| VPN | Virtual Private Network |
| VSAT | Very Small Aperture Terminal (satellite earth station) |
| VSB | Vestigial Side Band amplitude modulation (VSB/AM) |
| Vulnerabilities | - |
| wallet-to-wallet interactions | - |
| WAN | Wide Area Network |
| warrant | |
| warrantry | |
| WAS | Wireless Access Systems |
| Waste management | - |
| water consumption | - |
| W-band | - |
| WCDMA | Wideband Code-Division Multiple Access |
| WCG | Wide Colour Gamut |
| WDM | Wavelength Division Multiplexing |
| WDS | Wireless Data Systems |
| Wearable | - |
| WEEE | Waste of Electric and Electronical Equipment |
| white space | - |
| WIDE SCREEN | Wide Screen (16:9 aspect ratio for TV screens) |
| Wideband | - |
| WiMAX | |
| Wireless | - |
| wireless ad-hoc network | - |
| Wireless charger | - |
| wireless mesh network | - |
| wireless microphone | |
| wireless microphone system | |
| WLAN | - |
| WLL | Wireless Local Loop (DECT) |
| WMAN | Wireless Metropolitan Area Network |
| WMAS | - |
| WoT | Web of Things |
| WPT | Wireless Power Transmission |
| WRS | Wireless Relay Station (DECT) |
| WTM | Wireless Terminal Mobility |
| X.21 | CCITT Recommendation X.21 |
| X.25 | CCITT Recommendation X.25 |
| X.28 | CCITT Recommendation X.28 |
| X.31 | CCITT Recommendation X.31 |
| X.32 | CCITT Recommendation X.32 |
| X.500 | CCITT Recommendation X.500 |
| X.75 | CCITT Recommendation X.75 |
| XAdES | XML Advanced Electronic Signature |
| xDSL | (generic) Digital Subscriber Line |
| X-Haul | - |
| XML | Extensible Markup Language |
| XMLERS | - |
| YANG | Yet Another Next Generation |
US