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ITU-T Recommendation series structure

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ITU-T A-Series Recommendations: Organization of the work of ITU-T
A supplementsSupplements to the Series A Recommendations
ITU-T D-Series Recommendations: Tariff and accounting principles and international telecommunication/ICT economic and policy issues
D.0-D.0Terms and definitions
D.1-D.299General tariff principles
D.1-D.9Private leased telecommunication facilities
D.10-D.39Tariff principles applying to data communication services over dedicated public data networks
D.40-D.44Charging and accounting in the international public telegram service
D.45-D.49Charging and accounting in the international telemessage service
D.50-D.59Principles applicable to GII-Internet
D.60-D.69Charging and accounting in the international telex service
D.70-D.75Charging and accounting in the international facsimile service
D.76-D.79Charging and accounting in the international videotex service
D.80-D.89Charging and accounting in the international phototelegraph service
D.90-D.99Charging and accounting in the mobile services
D.100-D.159Charging and accounting in the international telephone service
D.160-D.179Drawing up and exchange of international telephone and telex accounts
D.180-D.184International sound- and television-programme transmissions
D.185-D.189Charging and accounting for international satellite services
D.190-D.191Transmission of monthly international accounting information
D.192-D.195Service and privilege telecommunications
D.196-D.209Settlement of international telecommunication balances of accounts
D.210-D.260Charging and accounting principles for international telecommunication services provided over the ISDN
D.261-D.269Economic and policy factors relevant to the efficient provision of international telecommunication services
D.270-D.279Charging and accounting principles for next generation networks (NGN)
D.280-D.284Charging and accounting principles for universal personal telecommunication
D.285-D.299Charging and accounting principles for intelligent network supported services
D.300-D.899Recommendations for regional application
D.300-D.399Recommendations applicable in Europe and the Mediterranean Basin
D.400-D.499Recommendations applicable in Latin America
D.500-D.599Recommendations applicable in Asia and Oceania
D.600-D.699Recommendations applicable to the African Region
D.700-D.799Recommendations applicable to the Arab Region
D.800-D.899Recommendations applicable to the Eastern Europe, Central Asia and Transcaucasia Region
D.1000-D.1199Recommendations for international telecommunication/ICT economic and policy issues
D.1000-D.1019Charging and accounting/settlement mechanisms for international telecommunications services
D.1020-D.1039Economic and policy factors relevant to the efficient provision of international telecommunication services
D.1040-D.1059International Internet connectivity; and Tariff, Charging Issues of Settlements Agreement of Trans-multi-country Terrestrial Telecommunication
D.1060-D.1079International mobile roaming issues
D.1080-D.1099Alternative calling procedures and misappropriation and misuse of facilities and services
D.1100-D.1119Economic and regulatory impact of the Internet, convergence (services or infrastructure) and new services
D.1120-D.1139Definition of relevant markets, competition policy and identification of operators with significant market power (SMP)
D.1140-D.1159Economic and policy aspects of big data and digital identity in international telecommunications services and networks
D.1160-D.1179Economic and policy issues pertaining to Mobile Financial Services (MFS)
D supplementsSupplements to ITU-T D-series D Recommendations
ITU-T E-Series Recommendations: Overall network operation, telephone service, service operation and human factors
E.100-E.229International operation
E.104-E.119General provisions concerning Administrations
E.120-E.139General provisions concerning users
E.140-E.159Operation of international telephone services
E.160-E.169Numbering plan of the international telephone service
E.170-E.179International routing plan
E.180-E.189Tones in national signalling systems
E.190-E.199Numbering plan of the international telephone service
E.200-E.229Maritime mobile service and public land mobile service
E.230-E.299Operational provisions relating to charging and accounting in the international telephone service
E.230-E.249Charging in the international telephone service
E.260-E.269Measuring and recording call durations for accounting purposes
E.300-E.329Utilization of the international telephone network for non-telephony applications
E.330-E.349ISDN provisions concerning users
E.350-E.399International routing plan
E.400-E.489Network management
E.400-E.404International service statistics
E.405-E.419International network management
E.420-E.489Checking the quality of the international telephone service
E.490-E.799Traffic engineering
E.490-E.505Measurement and recording of traffic
E.506-E.509Forecasting of traffic
E.510-E.519Determination of the number of circuits in manual operation
E.520-E.539Determination of the number of circuits in automatic and semi-automatic operation
E.540-E.599Grade of service
E.650-E.699Traffic engineering for IP-networks
E.700-E.749ISDN traffic engineering
E.750-E.799Mobile network traffic engineering
E.800-E.899Quality of telecommunication services: concepts, models, objectives and dependability planning
E.800-E.809Terms and definitions related to the quality of telecommunication services
E.810-E.844Models for telecommunication services
E.845-E.859Objectives for quality of service and related concepts of telecommunication services
E.860-E.879Use of quality of service objectives for planning of telecommunication networks
E.880-E.899Field data collection and evaluation on the performance of equipment, networks and services
E.1000-E.1999International operation
E.1100-E.1199Numbering plan of the international telephone service
E.4000-E.4999Network management
E.4100-E.4199International network management
E supplementsSupplements to the E-series Recommendations
E.100-E.399 supplementsSupplements to ITU-T E-series Recommendations relating to the operations of the international service
E.400-E.899 supplementsSupplements to ITU-T E-series Recommendations relating to telephone network management and traffic engineering
ITU-T F-Series Recommendations: Non-telephone telecommunication services
F.1-F.109Telegraph service
F.1-F.19Operating methods for the international public telegram service
F.20-F.29The gentex network
F.30-F.39Message switching
F.40-F.58The international telemessage service
F.59-F.89The international telex service
F.90-F.99Statistics and publications on international telegraph services
F.100-F.104Scheduled and leased communication services
F.105-F.109Phototelegraph service
F.110-F.159Mobile service
F.110-F.159Mobile services and multidestination satellite services
F.160-F.399Telematic services
F.160-F.199Public facsimile service
F.200-F.299Teletex service
F.300-F.349Videotex service
F.350-F.399General provisions for telematic services
F.400-F.499Message handling services
F.500-F.549Directory services
F.550-F.599Document communication
F.550-F.579Document communication
F.580-F.599Programming communication interfaces
F.600-F.699Data transmission services
F.700-F.799Multimedia services
F.800-F.849ISDN services
F.850-F.899Universal personal telecommunication
F.900-F.999Accessibility and human factors
F supplementsSupplements to ITU-T F-series Recommendations
ITU-T G-Series Recommendations: Transmission systems and media, digital systems and networks
G.100-G.199International telephone connections and circuits
G.100-G.109Transmission planning and the E-model
G.110-G.119General Recommendations on the transmission quality for an entire international telephone connection
G.120-G.129General characteristics of national systems forming part of international connections
G.130-G.139General characteristics of the 4-wire chain formed by the international circuits and national extension circuits
G.140-G.149General characteristics of the 4-wire chain of international circuits; international transit
G.150-G.159General characteristics of international telephone circuits and national extension circuits
G.160-G.169Apparatus associated with long-distance telephone circuits
G.170-G.179Transmission plan aspects of special circuits and connections using the international telephone connection network
G.180-G.189Protection and restoration of transmission systems
G.190-G.199Software tools for transmission systems
G.200-G.299General characteristics common to all analogue carrier-transmission systems
G.210-G.219Definitions and general considerations
G.220-G.229General Recommendations
G.230-G.239Translating equipment used on various carrier-transmission systems
G.240-G.299Utilization of groups, supergroups, etc.
G.300-G.399Individual characteristics of international carrier telephone systems on metallic lines
G.320-G.329Carrier telephone systems on unloaded symmetric cable pairs, providing groups or supergroups
G.330-G.339Carrier systems on 2.6/9.5 mm coaxial cable pairs
G.340-G.349Carrier systems on 1.2/4.4 mm coaxial cable pairs
G.350-G.399Additional Recommendations on cable systems
G.400-G.449General characteristics of international carrier telephone systems on radio-relay or satellite links and interconnection with metallic lines
G.400-G.419General Recommendations
G.420-G.429Interconnection of radio-relay links with carrier systems on metallic lines
G.430-G.439Hypothetical reference circuits
G.440-G.449Circuit noise
G.450-G.499Coordination of radiotelephony and line telephony
G.450-G.469Radiotelephone circuits
G.470-G.499Links with mobile stations
G.600-G.699Transmission media and optical systems characteristics
G.610-G.619Symmetric cable pairs
G.620-G.629Land coaxial cable pairs
G.630-G.639Submarine cables
G.640-G.649Free space optical systems
G.650-G.659Optical fibre cables
G.660-G.679Characteristics of optical components and subsystems
G.680-G.699Characteristics of optical systems
G.700-G.799Digital terminal equipments
G.710-G.729Coding of voice and audio signals
G.730-G.739Principal characteristics of primary multiplex equipment
G.740-G.749Principal characteristics of second order multiplex equipment
G.750-G.759Principal characteristics of higher order multiplex equipment
G.760-G.769Principal characteristics of transcoder and digital multiplication equipment
G.770-G.779Operations, administration and maintenance features of transmission equipment
G.780-G.789Principal characteristics of multiplexing equipment for the synchronous digital hierarchy
G.790-G.799Other terminal equipment
G.800-G.899Digital networks
G.800-G.809General aspects
G.810-G.819Design objectives for digital networks
G.820-G.829Synchronization, quality and availability targets
G.830-G.839Network capabilities and functions
G.840-G.849SDH network characteristics
G.850-G.859Management of transport network
G.860-G.869SDH radio and satellite systems integration
G.870-G.879Optical transport networks
G.900-G.999Digital sections and digital line system
G.910-G.919Parameters for optical fibre cable systems
G.920-G.929Digital sections at hierarchical bit rates based on a bit rate of 2048 kbit/s
G.930-G.939Digital line transmission systems on cable at non-hierarchical bit rates
G.940-G.949Digital line systems provided by FDM transmission bearers
G.950-G.959Digital line systems
G.960-G.969Digital section and digital transmission systems for customer access to ISDN
G.970-G.979Optical fibre submarine cable systems
G.980-G.989Optical line systems for local and access networks
G.990-G.999Metallic access networks
G.1000-G.1999Multimedia Quality of Service and performance – Generic and user-related aspects
G.6000-G.6999Transmission media characteristics
G.7000-G.7999Data over Transport – Generic aspects
G.7700-G.7799Transport network control aspects
G.8000-G.8999Packet over Transport aspects
G.8000-G.8099Ethernet over Transport aspects
G.8100-G.8199MPLS over Transport aspects
G.8200-G.8299Synchronization, quality and availability targets
G.8300-G.8399Mobile network transport aspects
G.8600-G.8699Service Management
G.9000-G.9999Access networks
G.9700-G.9799Metallic access networks
G.9800-G.9899Optical line systems for local and access networks
G.9900-G.9999In premises networks
G supplementsSupplements to ITU-T G-series Recommendations
ITU-T H-Series Recommendations: Audiovisual and multimedia systems
H.100-H.199Characteristics of visual telephone systems
H.200-H.499Infrastructure of audiovisual services
H.220-H.229Transmission multiplexing and synchronization
H.230-H.239Systems aspects
H.240-H.259Communication procedures
H.260-H.279Coding of moving video
H.280-H.299Related systems aspects
H.300-H.349Systems and terminal equipment for audiovisual services
H.350-H.359Directory services architecture for audiovisual and multimedia services
H.360-H.369Quality of service architecture for audiovisual and multimedia services
H.420-H.439Telepresence, immersive environments, virtual and extended reality
H.450-H.499Supplementary services for multimedia
H.500-H.549Mobility and Collaboration procedures
H.500-H.509Overview of Mobility and Collaboration, definitions, protocols and procedures
H.510-H.519Mobility for H-Series multimedia systems and services
H.520-H.529Mobile multimedia collaboration applications and services
H.530-H.539Security for mobile multimedia systems and services
H.540-H.549Security for mobile multimedia collaboration applications and services
H.550-H.599Vehicular gateways and intelligent transportation systems (ITS)
H.550-H.559Architecture for vehicular gateways
H.560-H.569Vehicular gateway interfaces
H.600-H.699Broadband, triple-play and advanced multimedia services
H.610-H.619Broadband multimedia services over VDSL
H.620-H.629Advanced multimedia services and applications
H.640-H.649Content delivery and ubiquitous sensor network applications
H.700-H.799IPTV multimedia services and applications for IPTV
H.700-H.719General aspects
H.720-H.729IPTV terminal devices
H.730-H.739IPTV middleware
H.740-H.749IPTV application event handling
H.750-H.759IPTV metadata
H.760-H.769IPTV multimedia application frameworks
H.770-H.779IPTV service discovery up to consumption
H.780-H.789Digital Signage
H.800-H.899E-health multimedia systems, services and applications
H.810-H.819Personal health systems
H.820-H.859Interoperability compliance testing of personal health systems (HRN, PAN, LAN, TAN and WAN)
H.860-H.869Multimedia e-health data exchange services
H.870-H.879Safe listening
H supplementsSupplements to ITU-T H-series Recommendations
ITU-T I-Series Recommendations: Integrated services digital network
I.100-I.199General structure
I.120-I.129Description of ISDNs
I.130-I.139General modelling methods
I.140-I.149Telecommunication network and service attributes
I.150-I.199General description of asynchronous transfer mode
I.200-I.299Service capabilities
I.210-I.219General aspects of services in ISDN
I.220-I.229Common aspects of services in the ISDN
I.230-I.239Bearer services supported by an ISDN
I.240-I.249Teleservices supported by an ISDN
I.250-I.259Supplementary services in ISDN
I.300-I.399Overall network aspects and functions
I.310-I.319Network functional principles
I.320-I.329Reference models
I.330-I.339Numbering, addressing and routing
I.340-I.349Connection types
I.350-I.359Performance objectives
I.360-I.369Protocol layer requirements
I.370-I.399General network requirements and functions
I.400-I.499ISDN user-network interfaces
I.410-I.429Application of I-series Recommendations to ISDN user-network interfaces
I.430-I.439Layer 1 Recommendations
I.440-I.449Layer 2 Recommendations
I.450-I.459Layer 3 Recommendations
I.460-I.469Multiplexing, rate adaption and support of existing interfaces
I.470-I.489Aspects of ISDN affecting terminal requirements
I.500-I.599Internetwork interfaces
I.600-I.699Maintenance principles
I.700-I.799B-ISDN equipment aspects
I.730-I.739ATM equipment
I.740-I.749Transport functions
I.750-I.759Management of ATM equipment
I.760-I.769Multiplexing aspects
I supplementsSupplements to ITU-T I-series Recommendations
ITU-T J-Series Recommendations: Cable networks and transmission of television, sound programme and other multimedia signals
J.1-J.9General Recommendations
J.10-J.19General specifications for analogue sound-programme transmission
J.20-J.29Performance characteristics of analogue sound-programme circuits
J.30-J.39Equipment and lines used for analogue sound-programme circuits
J.40-J.49Digital encoders for analogue sound-programme signals - Part 1
J.50-J.59Digital transmission of sound-programme signals
J.60-J.69Circuits for analogue television transmission
J.70-J.79Analogue television transmission over metallic lines and interconnection with radio-relay links
J.80-J.89Digital transmission of television signals
J.90-J.99Ancillary digital services for television transmission
J.100-J.109Operational requirements and methods for television transmission
J.110-J.129Interactive systems for digital television distribution (DOCSIS first and second generations)
J.130-J.139Transport of MPEG-2 signals on packetized networks
J.140-J.149Measurement of the quality of service - Part 1
J.150-J.159Digital television distribution through local subscriber networks
J.160-J.179IPCablecom (MGCP-based) - Part 1
J.180-J.189Digital transmission of television signals - Part 1
J.190-J.199Cable modems and home networking
J.200-J.209Application for Interactive Digital Television - Part 1
J.210-J.229Interactive systems for digital television distribution (DOCSIS third to fifth generations)
J.230-J.239Multi-device systems for cable television
J.240-J.249Measurement of the quality of service - Part 2
J.250-J.259Digital television distribution through local subscriber networks
J.260-J.279IPCablecom (MGCP-based) - Part 2
J.280-J.289Digital transmission of television signals - Part 2
J.290-J.299Cable set-top box
J.300-J.309Application for Interactive Digital Television - Part 2
J.340-J.349Measurement of the quality of service - Part 3
J.360-J.379IPCablecom2 (SIP-based) - Part 1
J.380-J.389Digital transmission of television signals - Part 3
J.440-J.449Measurement of the quality of service - Part 4
J.460-J.479IPCablecom2 (SIP-based) - Part 2
J.480-J.489Digital transmission of television signals - Part 4
J.600-J.699Transport of Large Screen Digital Imagery
J.700-J.799Secondary distribution of IPTV services
J.800-J.899Multimedia over IP in cable
J.900-J.999Transmission of 3-D TV services
J.900-J.909Free viewpoint TV
J.1000-J.1099Conditional access and protection
J.1000-J.1004Renewable conditional access system
J.1005-J.1009Digital rights management for cable television multiscreen service
J.1010-J.1019Exchangeable embedded conditional access and digital rights management solutions
J.1020-J.1025Downloadable system for multi-CA/DRM service of mobile broadcasting
J.1026-J.1029Downloadable conditional access system for unidirectional networks
J.1031-J.1035Downloadable conditional access system for bidirectional networks
J.1036-J.1039Factual subscriber-base reporting and protected content delivery in conditional access systems
J.1100-J.1119Switched digital video over cable networks
J.1200-J.1209Smart TV operating system
J.1210-J.1219IP Video Broadcast
J.1290-J.1299Cable set-top box - part 2
J.1300-J.1309Cloud-based converged media services for IP and broadcast cable television
J.1310-J.1319Cloud-based Services for IP Delivery over integrated broadband cable network
J.1400-J.1409Television transport network and system deployment in developing countries
J.1600-J.1649Artificial intelligence (AI) assisted cable networks
J.1600-J.1609General requirements for the AI-assisted cable network platform
J.1610-J.1619Requirements for the set-top box
J.1620-J.1629Interfaces between the AI-assisted cable network platform and set-top box
J.1630-J.1639Data models of the communicated data for the AI-assisted cable network platform
J.1640-J.1649Migration and applications of the AI-assisted cable networks
J supplementsSupplements to ITU-T J-series Recommendations
ITU-T K-Series Recommendations: Protection against interference
K supplementsSupplements to ITU-T K-series Recommendations
ITU-T L-Series Recommendations: Environment and ICTs, climate change, e-waste, energy efficiency; construction, installation and protection of cables and other elements of outside plant
L.100-L.199Optical fibre cables
L.100-L.124Cable structure and characteristics
L.125-L.149Cable evaluation
L.150-L.199Guidance and installation technique
L.200-L.299Optical infrastructures
L.200-L.249Infrastructure including node elements (except cables)
L.250-L.299General aspects and network design
L.300-L.399Maintenance and operation
L.300-L.329Optical fibre cable maintenance
L.330-L.349Infrastructure maintenance
L.350-L.379Operation support and infrastructure management
L.380-L.399Disaster management
L.400-L.429Passive optical devices
L.430-L.449Marinized terrestrial cables
L.1000-L.1199E-waste and circular economy
L.1200-L.1299Power feeding and energy storage
L.1300-L.1399Energy efficiency, smart energy and green data centres
L.1400-L.1499Assessment methodologies of ICTs and CO2 trajectories
L.1500-L.1599Adaptation to climate change
L.1600-L.1699Circular and sustainable cities and communities
L.1700-L.1799Low cost sustainable infrastructure
L supplementsSupplements to ITU-T L-series Recommendations
ITU-T M-Series Recommendations: Telecommunication management, including TMN and network maintenance
M.10-M.299Introduction and general principles of maintenance and maintenance organization
M.300-M.559International transmission systems
M.560-M.759International telephone circuits
M.760-M.799Common channel signalling systems
M.800-M.899International telegraph systems and phototelegraph transmission
M.900-M.999International leased group and supergroup links
M.1000-M.1099International leased circuits
M.1100-M.1199Mobile telecommunication systems and services
M.1200-M.1299International public telephone network
M.1300-M.1399International data transmission systems
M.1400-M.1999Designations and information exchange
M.2000-M.2999International transport network
M.3000-M.3599Telecommunications management network
M.3600-M.3999Integrated services digital networks
M.4000-M.4999Common channel signalling systems
M supplementsSupplements to the M-series Recommendations
ITU-T N-Series Recommendations: Maintenance: international sound programme and television transmission circuits
N.1-N.49International sound-programme transmission
N.50-N.79International television transmission
N.80-N.99International videoconference transmission
N supplementsSupplements to the Series N Recommendations
ITU-T O-Series Recommendations: Specifications of measuring equipment
O.10-O.19Maintenance access
O.20-O.39Automatic and semi-automatic measuring systems
O.40-O.129Equipment for the measurement of analogue parameters
O.130-O.199Equipment for the measurement of digital and analogue/digital parameters
O.200-O.209Equipment for the measurement of optical channel parameters
O.210-O.219Equipment to perform measurements on IP networks
O.220-O.229Equipment to perform measurements on leased-circuit services
O supplementsSupplements to the Series O Recommendations
ITU-T P-Series Recommendations: Telephone transmission quality, telephone installations, local line networks
P.10-P.19Vocabulary and effects of transmission parameters on customer opinion of transmission quality
P.30-P.39Voice terminal characteristics
P.40-P.49Reference systems
P.50-P.59Objective measuring apparatus
P.60-P.69Objective electro-acoustical measurements
P.70-P.79Measurements related to speech loudness
P.80-P.89Methods for objective and subjective assessment of speech quality
P.300-P.399Voice terminal characteristics
P.500-P.599Objective measuring apparatus
P.700-P.709Measurements related to speech loudness
P.800-P.899Methods for objective and subjective assessment of speech and video quality
P.900-P.999Audiovisual quality in multimedia services
P.1000-P.1099Transmission performance and QoS aspects of IP end-points
P.1100-P.1199Communications involving vehicles
P.1200-P.1299Models and tools for quality assessment of streamed media
P.1300-P.1399Telemeeting assessment
P.1400-P.1499Statistical analysis, evaluation and reporting guidelines of quality measurements
P.1500-P.1599Methods for objective and subjective assessment of quality of services other than speech and video
P supplementsSupplements to ITU-T P-series Recommendations
ITU-T Q-Series Recommendations: Switching and signalling, and associated measurements and tests
Q.1-Q.3Signalling in the international manual service
Q.4-Q.59International automatic and semi-automatic working
Q.4-Q.9Basic Recommendations
Q.10-Q.11Numbering plan and dialling procedures in the international service
Q.12-Q.19Routing plan for international service
Q.20-Q.34General Recommendations relative to signalling and switching systems (national or international)
Q.35-Q.39Tones for use in national signalling systems
Q.40-Q.47General characteristics for international telephone connections and circuits
Q.48-Q.49Signalling for satellite systems
Q.50-Q.59Signalling for circuit multiplication equipment
Q.60-Q.99Functions and information flows for services in the ISDN
Q.68-Q.79Basic services
Q.80-Q.99Supplementary services
Q.100-Q.119Clauses applicable to ITU-T standard systems
Q.100-Q.109General clauses
Q.110-Q.114Transmission clauses for signalling
Q.115-Q.115Logic and protocols for the control of signal processing network elements and functions
Q.116-Q.119Abnormal conditions
Q.120-Q.499Specifications of Signalling Systems No. 4, 5, 6, R1 and R2
Q.500-Q.599Digital exchanges
Q.500-Q.509Introduction and field of application
Q.510-Q.539Exchange interfaces, functions and connections
Q.540-Q.549Design objectives and measurement
Q.550-Q.559Transmission characteristics
Q.600-Q.699Interworking of Signalling Systems
Q.600-Q.609General considerations
Q.610-Q.697Logic procedures
Q.698-Q.698Interworking of Signalling Systems No. 7 and No. 6
Q.699-Q.699Interworking between Digital Subscriber Signalling System No. 1 and Signalling System No. 7
Q.700-Q.799Specifications of Signalling System No. 7
Q.701-Q.710Message transfer part (MTP)
Q.711-Q.719Signalling connection control part (SCCP)
Q.720-Q.729Telephone user part (TUP)
Q.730-Q.739ISDN supplementary services
Q.740-Q.749Data user part
Q.750-Q.759Signalling System No. 7 management
Q.760-Q.769ISDN user part
Q.770-Q.779Transaction capabilities application part
Q.780-Q.799Test specification
Q.800-Q.849Q3 interface
Q.850-Q.999Digital subscriber Signalling System No. 1
Q.920-Q.929Data link layer
Q.930-Q.939Network layer
Q.940-Q.949User-network management
Q.950-Q.959Stage 3 description for supplementary services using DSS1
Q.1000-Q.1099Public land mobile network
Q.1030-Q.1049Interworking with ISDN and PSTN
Q.1050-Q.1059Mobile Application Part
Q.1060-Q.1069Digital PLMN user-network interfaces
Q.1100-Q.1199Interworking with satellite mobile systems
Q.1100-Q.1109Interworking with Standard-A INMARSAT system
Q.1110-Q.1149Interworking with Standard-B INMARSAT system
Q.1150-Q.1199Interworking with the INMARSAT aeronautical mobile-satellite system
Q.1200-Q.1699Intelligent Network
Q.1700-Q.1799Signalling requirements and protocols for IMT-2000
Q.1900-Q.1999Specifications of signalling related to Bearer Independent Call Control (BICC)
Q.2000-Q.2999Broadband ISDN
Q.2000-Q.2099General aspects
Q.2100-Q.2199Signalling ATM adaptation layer (SAAL)
Q.2200-Q.2299Signalling network protocols
Q.2600-Q.2699Common aspects of B-ISDN application protocols for access signalling and network signalling and interworking
Q.2700-Q.2899B-ISDN application protocols for the network signalling
Q.2900-Q.2999B-ISDN application protocols for access signalling
Q.3000-Q.3709Signalling requirements and protocols for the NGN
Q.3030-Q.3099Network signalling and control functional architecture
Q.3100-Q.3129Network data organization within the NGN
Q.3130-Q.3179Bearer control signalling
Q.3200-Q.3249Signalling and control requirements and protocols to support attachment in NGN environments
Q.3300-Q.3369Resource control protocols
Q.3400-Q.3499Service and session control protocols
Q.3600-Q.3616Service and session control protocols – supplementary services
Q.3617-Q.3639Service and session control protocols – supplementary services based on SIP-IMS
Q.3640-Q.3655VoLTE/ViLTE network signalling
Q.3700-Q.3709NGN applications
Q.3710-Q.3899Signalling requirements and protocols for SDN
Q.3710-Q.3739Resource control protocols
Q.3740-Q.3779Network signalling and signalling requirements for services
Q.3900-Q.4099Testing specifications
Q.3900-Q.3999Testing specifications for next generation networks
Q.4000-Q.4039Testing specifications for SIP-IMS
Q.4040-Q.4059Testing specifications for Cloud computing
Q.4060-Q.4099Testing specifications for IMT-2020 and IoT
Q.4100-Q.4139Protocols and signalling for peer-to-peer communications
Q.4140-Q.4159Protocols and signalling for computing power networks
Q.4160-Q.4179Protocols and signalling for Quantum key distribution networks
Q.5000-Q.5049Signalling requirements and protocols for IMT-2020
Q.5000-Q.5019Signalling requirements and architecture of IMT-2020
Q.5020-Q.5049Protocols for IMT-2020
Q.5050-Q.5069Combating counterfeiting and stolen ICT devices
Q supplementsSupplements to ITU-T Q-series Recommendations
ITU-T R-Series Recommendations: Telegraph transmission
R.1-R.19Telegraph distortion
R.20-R.39Voice-frequency telegraphy
R.40-R.49Special cases of alternating current telegraphy
R.50-R.59Transmission quality
R.60-R.69Correction of signals
R.70-R.99Telegraph maintenance
R.100-R.119Time-division multiplexing
R.120-R.139Transmission quality above 50 bauds
R.150-R.159Availability and reliability of international telegraph circuits
ITU-T S-Series Recommendations: Telegraph services terminal equipment
S.1-S.139Start-stop terminals
S supplementsSupplements to ITU-T S-series Recommendations
ITU-T T-Series Recommendations: Terminals for telematic services
T.0-T.19Facsimile – Framework
T.20-T.29Still-image compression – Test charts
T.30-T.39Facsimile – Group 3 protocols
T.40-T.49Colour representation
T.50-T.59Character coding
T.60-T.69Facsimile – Group 4 protocols
T.70-T.79Telematic services – Framework
T.80-T.89Still-image compression – JPEG-1, Bi-level and JBIG
T.90-T.99Telematic services – ISDN Terminals and protocols
T.100-T.109Videotext – Framework
T.120-T.149Data protocols for multimedia conferencing
T.170-T.189Multimedia and hypermedia framework
T.190-T.199Cooperative document handling
T.300-T.399Telematic services – Interworking
T.400-T.429Open document architecture
T.430-T.449Document transfer and manipulation
T.500-T.509Document application profile
T.510-T.559Communication application profile
T.560-T.619Telematic services – Equipment characteristics
T.620-T.649General multimedia application frameworks
T.700-T.799User interfaces - Accessibility and human factors
T.800-T.829Still-image compression – JPEG 2000
T.830-T.849Still-image compression | JPEG XR
T.850-T.899Still-image compression – JPEG-1 extensions
T supplementsSupplements to the Series T Recommendations
ITU-T U-Series Recommendations: Telegraph switching
U.11-U.19Specific signalling schemes and interworking between signalling systems
U.20-U.29Signalling over radio and multiplexed channels
U.30-U.39Gentex signalling
U.40-U.59Particular signalling facilities
U.60-U.69Radiotelex interworking
U.70-U.79Interworking between new information services and telex
U.80-U.99Telex store and forward
U.100-U.139Intex service
U.200-U.299The international telex service
U supplementsSupplements to the Series U Recommendations
ITU-T V-Series Recommendations: Data communication over the telephone network
V.10-V.34Interfaces and voiceband modems
V.35-V.39Wideband modems
V.40-V.49Error control
V.50-V.59Transmission quality and maintenance
V.60-V.99Simultaneous transmission of data and other signals
V.100-V.199Interworking with other networks
V.200-V.249Interface layer specifications for data communication
V.250-V.299Control procedures
V.300-V.399Modems on digital circuits
V supplementsSupplements to the Series V Recommendations
ITU-T X-Series Recommendations: Data networks, open system communications and security
X.1-X.199Public data networks
X.1-X.19Services and facilities
X.50-X.89Transmission, signalling and switching
X.90-X.149Network aspects
X.180-X.199Administrative arrangements
X.200-X.299Open Systems Interconnection
X.200-X.209Model and notation
X.210-X.219Service definitions
X.220-X.229Connection-mode protocol specifications
X.230-X.239Connectionless-mode protocol specifications
X.240-X.259PICS proformas
X.260-X.269Protocol Identification
X.270-X.279Security Protocols
X.280-X.289Layer Managed Objects
X.290-X.299Conformance testing
X.300-X.399Interworking between networks
X.350-X.369Satellite data transmission systems
X.370-X.379IP-based networks
X.400-X.499Message Handling Systems
X.600-X.699OSI networking and system aspects
X.640-X.649Quality of service
X.650-X.679Naming, Addressing and Registration
X.680-X.699Abstract Syntax Notation One (ASN.1)
X.700-X.799OSI management
X.700-X.709Systems management framework and architecture
X.710-X.719Management communication service and protocol
X.720-X.729Structure of management information
X.730-X.799Management functions and ODMA functions
X.850-X.899OSI applications
X.850-X.859Commitment, concurrency and recovery
X.860-X.879Transaction processing
X.880-X.889Remote operations
X.890-X.899Generic applications of ASN.1
X.900-X.999Open distributed processing
X.1000-X.1099Information and network security
X.1000-X.1011Security orchestration and service access
X.1012-X.1029Security architecture and capabilities
X.1030-X.1049Network security
X.1050-X.1079Security management
X.1100-X.1199Secure applications and services (I)
X.1100-X.1109Multicast security
X.1110-X.1119Home network security
X.1120-X.1139Mobile security
X.1140-X.1149Web security (I)
X.1150-X.1159Application Security (I)
X.1160-X.1164Peer-to-peer security
X.1165-X.1179Data protection (I) and networked ID security
X.1180-X.1189Countering fraud
X.1190-X.1199IPTV security
X.1200-X.1299Cyberspace security
X.1230-X.1249Countering spam
X.1250-X.1299Identity management (IdM) and Authentication
X.1300-X.1499Secure applications and services (II)
X.1300-X.1309Emergency communications
X.1310-X.1319Ubiquitous sensor network security
X.1330-X.1339Smart grid security
X.1340-X.1349Certified mail
X.1350-X.1369Internet of things (IoT) security
X.1370-X.1399Intelligent transportation system (ITS) security
X.1400-X.1429Distributed ledger technology (DLT) security
X.1450-X.1459Application Security (2)
X.1470-X.1489Web security (2)
X.1500-X.1599Cybersecurity information exchange
X.1500-X.1519Overview of cybersecurity
X.1520-X.1539Vulnerability/state exchange
X.1540-X.1549Event/incident/heuristics exchange
X.1550-X.1559Exchange of policies
X.1560-X.1569Cyber defence
X.1570-X.1579Identification and discovery
X.1580-X.1599Assured exchange
X.1600-X.1699Cloud computing security
X.1600-X.1601Overview of cloud computing security
X.1602-X.1629Cloud computing security requirements, security capabilities
X.1630-X.1639Cloud computing security controls
X.1640-X.1659Cloud computing security best practices and guidelines
X.1660-X.1699Other cloud computing security
X.1700-X.1729Quantum communication
X.1702-X.1704Quantum random number generator
X.1705-X.1749Quantum Key Distribution Network (QKDN)
X.1750-X.1799Data security
X.1750-X.1759Big Data Security
X.1770-X.1799Data protection (II)
X.1800-X.1839International Mobile Telecommunications (IMT) security
X.1810-X.1839IMT-2020 security
X.2000-X.2199Metaverse and digital twin security
X.2000-X.2049Digital twins
X.2050-X.2099Smart community
X.2100-X.2149Oher metaverse security
X.2150-X.2199Software supply chain security
X.2200-X.2249Artificial Intelligence (AI) / Machine Learning (ML) security
X supplementsSupplements to ITU-T X-series Recommendations
ITU-T Y-Series Recommendations: Global information infrastructure, Internet protocol aspects, next-generation networks, Internet of Things and smart cities
Y.100-Y.999Global information infrastructure
Y.200-Y.299Services, applications and middleware
Y.300-Y.399Network aspects
Y.400-Y.499Interfaces and protocols
Y.500-Y.599Numbering, addressing and naming
Y.600-Y.699Operation, administration and maintenance
Y.1000-Y.1999Internet protocol aspects
Y.1100-Y.1199Services and applications
Y.1200-Y.1299Architecture, access, network capabilities and resource management
Y.1500-Y.1599Quality of service and network performance
Y.1700-Y.1799Operation, administration and maintenance
Y.1900-Y.1999IPTV over NGN
Y.2000-Y.2999Next Generation Networks
Y.2000-Y.2099Frameworks and functional architecture models
Y.2100-Y.2199Quality of Service and performance
Y.2200-Y.2249Service aspects: Service capabilities and service architecture
Y.2250-Y.2299Service aspects: Interoperability of services and networks in NGN
Y.2300-Y.2399Enhancements to NGN
Y.2400-Y.2499Network management
Y.2500-Y.2599Computing power networks
Y.2600-Y.2699Packet-based Networks
Y.2800-Y.2899Generalized mobility
Y.2900-Y.2999Carrier grade open environment
Y.3000-Y.3499Future networks
Y.3500-Y.3599Cloud Computing
Y.3600-Y.3799Big Data
Y.3800-Y.3999Quantum key distribution networks
Y.4000-Y.4999Internet of things and smart cities and communities
Y.4050-Y.4099Definitions and terminologies
Y.4100-Y.4249Requirements and use cases
Y.4250-Y.4399Infrastructure, connectivity and networks
Y.4400-Y.4549Frameworks, architectures and protocols
Y.4550-Y.4699Services, applications, computation and data processing
Y.4700-Y.4799Management, control and performance
Y.4800-Y.4899Identification and security
Y.4900-Y.4999Evaluation and assessment
Y supplementsSupplements to the Y-series Recommendations
Y.2000-Y.3000 supplementsSupplements to the Y-series Recommendations relating to the Next Generation Networks
Y.4000-Y.5000 supplementsSupplements to the Y-series Recommendations relatedto IoT and SC&C
ITU-T Z-Series Recommendations: Languages and general software aspects for telecommunication systems
Z.100-Z.199Formal description techniques (FDT)
Z.100-Z.109Specification and Description Language (SDL)
Z.110-Z.119Application of formal description techniques
Z.120-Z.129Message Sequence Chart (MSC)
Z.150-Z.159User Requirements Notation (URN)
Z.160-Z.179Testing and Test Control Notation (TTCN)
Z.200-Z.299Programming languages
Z.200-Z.209CHILL: The ITU-T high level language
Z.300-Z.399Man-machine language
Z.300-Z.309General principles
Z.310-Z.319Basic syntax and dialogue procedures
Z.320-Z.329Extended MML for visual display terminals
Z.330-Z.349Specification of the man-machine interface
Z.350-Z.359Data-oriented human-machine interfaces
Z.360-Z.379Human-machine interfaces for the management of telecommunications networks
Z.400-Z.409Quality of telecommunication software
Z.450-Z.459Quality aspects of protocol-related Recommendations
Z.500-Z.519Methods for validation and testing
Z.600-Z.609Processing environment architectures
Z supplementsSupplements to the Z-series