They may not be directly comparable with Persona, but such things are widely deployed in academic/research communities: https://shibboleth.net/ https://shibbole

They may not be directly comparable with Persona, but such things are widely deployed in academic/research communities: https://shibboleth.net/ https://shibboleth.net/ (web-specific), https://www.eduroam.org/ https://www.eduroam.org/ (roaming wifi-specific in practice?), and "e-science certificates" in the UK (specifically horrible -- definitely not a beautiful thing) which I think come under https://www.igtf.net/ https://www.igtf.net/. The recent generalized effort is Moonshot/ABFAB (https://jisc.ac.uk/assent https://jisc.ac.uk/assent), which I think has made disappointingly slow progress.