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Multi-Factor Authentication (or MFA) requires you to use more than one method to prove your identity. An example would be entering your username and password (method 1) and approving a Duo authentication request on your phone (method 2).
Recommended MFA Authentication Options
The following are recommended MFA authentication options.
Verified Duo Push
Hardware Token
The following are considered less secure MFA authentication options and should be avoided in favor of the options listed above.
Phone Call
SMS / Text Message
Duo Help Docs
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