ITU-T continues studying quantum-resistant support
1 JANUARY 2025, GENEVA
The ITU-T, the standardization arm of the International Telecommunication Union, continues studying quantum-resistant support. It published recommendation X.1811 in 2021, scoped specifically to 5G, and its Study Group 17 under Question 11 is examining changes to X.509 certificates. The work remains in study across much of its scope rather than settled into broad recommendations.
The X.509 work is the piece with the widest reach. X.509 is the standard format for the digital certificates that underpin secure connections and identity across the internet, so adapting it for post-quantum algorithms is necessary for quantum-resistant certificates to work at scale. That is why a dedicated study group examines the changes the format needs.
X.1811's narrower scope shows the ITU-T addressing specific domains first. By covering 5G in 2021 while the broader certificate work continues, the ITU-T delivered targeted guidance where it could, leaving the larger X.509 question to ongoing study. Organizations should treat the ITU-T's quantum-resistant guidance as developing rather than complete.
Why it matters. The ITU-T's work matters most for the certificate ecosystem, where X.509 changes will shape how quantum-resistant certificates function across networks. With X.1811 covering 5G and the X.509 work still under study, the guidance is evolving. Organizations that rely on telecom standards or digital certificates should track Study Group 17, since its recommendations will influence how vendors build and deploy post-quantum certificates.