Hi Oban3jimmy,
Yes you have the right link for configuration on Junos Space end for user authentication. And yes, to user windows server for authentication, MSCHAPv2 is a popular choice.
Configure Junos Space for Radius Authentication (details on the link you shared) and you eed to enable Radius Server role on Windows to share authentication packets with Junos Space. Sample link: https://theitbros.com/radius-server-configuration-on-windows/
Hope that resolves your query and hope this helps.
Regards,
-r.
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