MFA grants user access only after successfully presenting several separate pieces of evidence to an authentication mechanism, usually at least two of the following categories—knowledge (something they know), possession (something they have), and inherence (something they are).

Two-factor authentication (2FA) is a type of MFA where just two components are used.

Starting with vSphere 6.0 Update 2, it is possible to have a 2FA using the following:

• Smart card (UPN-based Common Access Card or CAC)
• RSA SecurID token

 vCenter SSO supports only native SecurID and does not support RADIUS authentication.