ITU-T Recommendations

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• Series A Recommendations - Organization of the work of the ITU-T (12)
• Series B Recommendations - Means of expression (definitions, symbols, classification) (13)
• Series C Recommendations - General telecommunication statistics (4)
• Series D Recommendations- General tariff principles (124)
• Series E Recommendations - Overall network operation (numbering, routing, network management, operational performance and traffic engineering); telephone service, service operation and human factors (169)
• Series F Recommendations - Telecommunication services other than telephone (operations, quality of service, service definitions and human factors) (123)
• Series G Recommendations - Transmission systems and media, digital systems and networks (211)
• Series H Recommendations - Line transmission of non-telephone signals (19)
• Series I Recommendations - Integrated Services Digital Networks (ISDN) (122)
• Series J Recommendations - Transmission of sound programme and television signals (35)
• Series K Recommendations - Protection against interference (35)
• Series L Recommendations - Construction, installation and protection of cable and other elements of outside plant (17)
• Series M Recommendations - Maintenance: international transmission systems, telephone circuits, telegraphy, facsimile and leased cicuits (63)
• Series N Recommendations - Maintenance: international sound programme and television transmission circuits (9)
• Series O Recommendations - Specifications of measuring equipment (12)
• Series P Recommendations - Telephone transmission quality, telephone installations, local line networks (42)
• Series Q Recommendations - Switching and Signalling (3)
• Series R Recommendations - Telegraph transmission (70)
• Series S Recommendations - Telegraph services terminal equipment (29)
• Series T Recommendations - Terminal characteristics and higher layer protocols for telematic services, document architecture (84)
• Series U Recommendations - Telegraph switching (47)
• Series V Recommendations - Data communication over the telephone network (58)
• Series X Recommendations - Data networks and open system communication (209)
• Series Z Recommendations - Programming languages (28)

• How to order ITU-T Recommendations (2)
• List of ITU-T A-Series Recommendations in force (1)
• List of ITU-T B-Series Recommendations in force (1)
• List of ITU-T C-Series Recommendations in force (1)
• List of ITU-T D-Series Recommendations in force (1)
• List of ITU-T E-Series Recommendations in force (1)
• List of ITU-T F-Series Recommendations in force (1)
• List of ITU-T G-Series Recommendations in force (1)
• List of ITU-T H-Series Recommendations in force (1)
• List of ITU-T I-Series Recommendations in force (1)
• List of ITU-T J-Series Recommendations in force (1)
• List of ITU-T K-Series Recommendations in force (1)
• List of ITU-T L-Series Recommendations in force (1)
• List of ITU-T M-Series Recommendations in force (1)
• List of ITU-T N-Series Recommendations in force (1)
• List of ITU-T O-Series Recommendations in force (1)
• List of ITU-T P-Series Recommendations in force (1)
• List of ITU-T Q-Series Recommendations in force (1)
• List of ITU-T R-Series Recommendations in force (1)
• List of ITU-T S-Series Recommendations in force (1)
• List of ITU-T T-Series Recommendations in force (1)
• List of ITU-T U-Series Recommendations in force (1)
• List of ITU-T V-Series Recommendations in force (1)
• List of ITU-T X-Series Recommendations in force (1)
• List of ITU-T Z-Series Recommendations in force (1)
• List of ITU-T Recommendations in force (1)
• List of ITU-T Recommendations currently under ballot (Resolution No. 1, Section 8, of the WTSC, Helsinki 1993) (2)
• List of obsolete ITU-T Recommendations cancelled by the WTSC-93 (1)
• List of ITU-T Recommendations proposed for approval in accordance with Resolution No.1, Section 8, of the WTSC (Helsinki, 1993) (2)
• List of obsolete Recommendations cancelled during Study Period 1993-1996 (2)