I have a SonicWall TZ-210.
I want an extremely easy way to limit external remote access to the VPN beyond just username and password, but I do not wish to buy/deploy a OTP appliance because that is overkill for my situation.
I also do not want to use IPSec because my remote users are roaming.
I want the user to be in physical possession of something, whether that is a pre-configured client with an encrypted key or a certificate .cer/.pfx of some sort.
SonicWall used to offer "Certificate Services" for authentication, but apparently discontinued that a long time ago. So, what is everyone using in its place?
Beyond the "Fortune 500" expensive solution, how do I limit access to the VPN to only those users who have possession of a certificate file or some other file or something beyond passwords?