ITU-T Recommendations

Series A - Organization of the work of the ITU-T

Series B - Means of expression

Series C - General telecommunication statistics

Series D - General tariff principles

Series E - Telephone network and ISDN

Series F - Non-telephone telecommunication services

Series G - Transmission systems and media

Series H - Transmission of non-telephone signals

Series I - Integrated services digital network

Series J - Transmission of sound-programme and television signals

Series K - Protection against interference

Series L - Construction, installation and protection of cables and other elements of outside plant

Series M - Maintenance: international transmission systems, telephone circuits, telegraphy, facsimile and lease circuits

Series N - Maintenance: international sound-programme and television transmission circuits

Series O - Specifications of measuring equipment

Series P - Telephone transmission quality

Series Q - Switching and signalling

Series R - Telegraph transmission

Series S - Telegraph services terminal equipment

Series T - Terminal equipments and protocols for telematic services

Series U - Telegraph switching

Series V - Data communication over the telephone network

Series X - Data networks and open system communication

Series Z - Programming languages