What Is TOTP Mode in Google Authenticator?

Google Authenticator is a popular two-factor authentication (2FA) app used by many individuals and organizations to provide an extra layer of security for their online accounts. One of the key features of Google Authenticator is its ability to generate one-time passwords using TOTP mode. But what exactly is TOTP mode, and how does it work?

In simple terms, TOTP (Time-Based One-Time Password) is a type of 2FA that generates a unique password every 30 seconds based on the current time. This password is valid for only a short period, typically 30 seconds, before it expires and a new one takes its place.

To generate tokens in TOTP mode, you can use oathtool, a command-line tool available in the oathtool package. When using oathtool, you'll need to specify several variables, including the algorithm (ALGO), secret key (SECRET), number of digits (N), and period (MM).

For example, the following command would generate a TOTP token:

oathtool -totp=ALGO -b SECRET -d N -s MM

The resulting token can then be entered in place of your regular password when logging into an account.

In addition to using oathtool, you can also use a QR code to set up TOTP mode on Google Authenticator. To do this, you'll need to scan the QR code using a tool like zbarimg or zbarcam, which is available in the zbar-tools package. The QR code will contain the secret data for your TOTP token, and once scanned, it can be used to generate one-time passwords.

Overall, TOTP mode is an important part of Google Authenticator's 2FA capabilities, providing an additional layer of security for individuals and organizations alike. By understanding how TOTP mode works and how to use it, you can take advantage of the added protection it offers and help keep your online accounts safe from unauthorized access.

What is totp mode in google authenticator