Two-Factor AuthenticationTime based OTP (TOPT)

Two-Factor Authentication (2FA) is an extra layer of security used to make sure that people trying to gain access to an online account are who they say they are. First, a user will enter their username and a password. Then, instead of immediately gaining access, they will be required to provide another piece of information.

Time-based One-Time Password (TOTP) is a single-use passcode typically used for authenticating users. The user is assigned a TOPT generator delivered as a hardware key fob or software token. The generator implements an algorithm that computes a one-time passcode using a secret shared with the authentication server and the current time – hence the name time-based OTP. The passcode is displayed to the user and is valid for a limited duration. Once expired, the passcode is no longer valid. The user enters a valid passcode into a login form, typically together with his username and regular password.

Time-based one-time password (TOTP) is a computer algorithm that generates a one-time password (OTP) that uses the current time as a source of uniqueness. As an extension of the HMAC-based one-time password algorithm (HOTP), it has been adopted as Internet Engineering Task Force (IETF) standard RFC 6238.

QR code (an initialism for quick response code) is a type of matrix barcode (or two-dimensional barcode) invented in 1994 by the Japanese automotive company Denso Wave. A barcode is a machine-readable optical label that can contain information about the item to which it is attached. In practice, QR codes often contain data for a locator, identifier, or tracker that points to a website or application. .