Двухфакторная аутентификация
Two-Factor Authentication
Two-factor authentication (2FA) is a login method that requires two independent factors to confirm identity, for example a password and a one-time code from an app.
What is Двухфакторная аутентификация (Two-Factor Authentication)?
## How it works
There are three types of authentication factors: something you know (password, PIN), something you have (phone, token, hardware key), and something you are (biometrics). 2FA combines two different types, so a stolen password alone does not give access to the account.
## Where it is used and which factors are chosen
On crypto exchanges and wallets, 2FA is usually mandatory for logging in, withdrawing funds, and changing settings. In fintech and payments, a second factor is often required to confirm transactions, and in the EU strong customer authentication is set out in PSD2. In gambling, betting, and dating, account protection is needed because of money and personal data. In nutra and affiliate marketing, 2FA protects ad accounts, trackers, and social media profiles, where account takeovers are common. The most common options are time-based one-time passwords (TOTP) in authenticator apps, push confirmations, and hardware keys based on the FIDO2 standard. SMS codes are considered the weakest option because of the risk of SIM interception and phishing.
## What it affects
2FA reduces the share of account takeovers and unauthorized withdrawals, but it adds friction: users abandon sign-up or login if the step is too complicated. Teams usually enable 2FA for sensitive actions rather than on every login, and test how many users drop off at this step.
## Common mistakes
Typical mistakes include relying only on SMS without accounting for SIM swap; storing backup codes in plain text; a shared team account without a second factor; and approving push requests without checking context, which leads to MFA fatigue attacks.
FAQ
How is two-factor authentication different from two-step verification?
In essence they describe the same thing: verification using two factors. Two-step verification more often refers to the login process, while two-factor authentication refers to the types of factors being used.
Which 2FA option is the most secure?
Hardware keys based on the FIDO2 standard are considered the most resistant to phishing. TOTP codes in an app are more reliable than SMS because they do not depend on the mobile carrier.
What should you do if you lose your second factor?
Usually backup codes issued during 2FA setup help, or a recovery process through support with identity verification. Backup codes should be stored separately from the password.