Starting this summer, you’ll see greater use of Duo multi-factor authentication at UC Davis. And as use grows, the damage caused by phishing will shrink.

Duo is a security app. It works by asking you for two “factors” when you sign in to an account protected by Duo: your usual password, plus a temporary code created by Duo, typically sent via the Duo app to your smartphone. (There are alternatives if you can’t use a smartphone—more below.)