> For the complete documentation index, see [llms.txt](https://help.cymmetri.io/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://help.cymmetri.io/single-sign-on/passwordless/totp-based.md).

# TOTP Based

Time-based One-Time Password (TOTP) authentication is a two-factor authentication mechanism that uses a time-based algorithm to generate a unique one-time password for user authentication. TOTP is commonly used in security systems, including various two-factor authentication (2FA) applications and services.

In Cymmetri the totp is received on the users mobile device during the login attempt after having it been configured during first login. 

During login the user is shown the option of Passwordless if it has been enabled by the admin user.

<figure><img src="/files/Y3V6DhToFeuTG9hcRfSq" alt=""><figcaption></figcaption></figure>

The user clicks on "Login without password" to proceed with Passwordless authentication.&#x20;

<figure><img src="/files/fVqH0Cn7JixddFBxrhvA" alt=""><figcaption></figcaption></figure>

The user clicks on TOTP based option.

<figure><img src="/files/VXDVUJGH8YCNU5k6fUpy" alt=""><figcaption></figcaption></figure>

A TOTP for the user has been configured on the users Cymmetri mobile application. The user inputs the totp and is logged in into the system