Hi @RobHuijser ,
Radius only encrypts the password section of the packet. Other information, such as username, authorized services, and accounting, can be captured by a third party. the best recommendation is to deploy the authentication server on-premises or over a VPN than putting it out on the Internet. Many cloud hosters like AWS, Azure, and Google provide IPsec VPN services, it is worth to establish a VPN tunnel to secure the packets.
Otherwise, you can leverage something like TACACS which will encrypt the entire packet, unlike Radius.
Cheers!
Raj
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