ITU-T Recommendations

​​The main products of ITU-T are Recommendations (ITU-T Recs) - standards defining how telecommunication networks operate and interwork. These can be accessed through the links below. ITU-T Recs have non-mandatory status until they are adopted in national laws. The level of compliance is nonetheless high due to international applicability and the high quality guaranteed by ITU-T's secretariat, and members from the world's foremost information and communication technology (ICT) companies and global administrations.

There are over 4000 Recommendations in force on topics from service definition to network architecture and security, from broadband DSL to Gbit/s optical transmission systems, next-generation networks (NGN) and IP-related issues. All of these topics make part of the fundamental components of today's ICTs.

Membership of ITU-T gives exclusive rights to access working documents of standards under development – tomorrow's ICTs. The vast majority of all Recommendations are available in electronic (PDF) form, free of charge to all, once the final, edited version is published. Texts that are not free of charge include common ITU-T | ISO / IEC texts for which special arrangements exist. Find out more about membership here.

ITU-T Recommendations are available through the Website in tree views, offering multi-criteria search and cross navigation facilities. Each ITU-T Recommendation is cross-linked to the corresponding work programme item, Alternative and Traditional Approval Processes, formal descriptions (more than 1400 freely available), test signals (more than 15 GB of data freely available), supplements, implementer's guides, and IPR statements when applicable.

• ITU-T Recommendation series structure
• ITU-T Recommendations keyword search
• Latest ITU-T Publications
• ITU-T Recommendations under AAP (Alternative Approval Process)
• ITU-T Recommendations under TAP (Traditional Approval Process)
• Common (identical) and twin (equivalent) texts with ISO/IEC
• Order the compendium (USB key) of all ITU-T Recommendations in force