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HARICA is the CA backing the GÉANT Certificate Service since January 2025. The server certificate issued by the service comes with the GEANT intermediate certificate. It is recommended to also add the Cross Certificate from HARICA Root CA 2015 to 2021 as a second intermediate certificate to the RADIUS server after the GÉANT intermediate certificate. This way, supplicants with knowledge of only the Root CA 2015 could still connect securely. It is recommended to put only the HARICA TLS Root CA 2021 to eduroam CAT for usage during onboarding, but you may experience problems with Windows clients forcing you to also add the HARICA TLS Root CA 2015 to eduroam CAT.
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