Hello @Charlie Melga ,
Thank you for posting here.
For Certificate authentication to Windows Active Directory, you need CA (Windows CA or non-Windows CA or third-party CA) server, certificates and smart card.
For more information, please refer to link below.
Guidelines for enabling smart card logon with third-party certification authorities
https://learn.microsoft.com/en-us/troubleshoot/windows-server/windows-security/enabling-smart-card-logon-third-party-certification-authorities
ADCS Step by Step Guide: Single Tier PKI Hierarchy Deployment
https://social.technet.microsoft.com/wiki/contents/articles/11750.adcs-step-by-step-guide-single-tier-pki-hierarchy-deployment.aspx
AD CS Step by Step Guide: Two Tier PKI Hierarchy Deployment
https://social.technet.microsoft.com/wiki/contents/articles/15037.ad-cs-step-by-step-guide-two-tier-pki-hierarchy-deployment.aspx
Hope the information above is helpful to you.
Should you have any question or concern, please feel free to let us know.
Best Regards,
Daisy Zhou
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