What is two-factor authentication?

Two-factor authentication (2FA) is a security measure that requires the user to verify their identity using two different factors before access is granted. The purpose is to add an extra layer of protection beyond the traditional password and reduce the risk of unauthorised access. Even if a hacker gets hold of a password, they will still lack the second factor, making it significantly harder to compromise an account.

2FA relies on three main categories of authentication:

1. Something you know (passwords or PINs)
2. Something you have (a phone, security key or one-time code generator)
3. Something you are (biometric data like fingerprints or facial recognition).

Combining two of these factors provides a higher level of security, making it more difficult for attackers to gain unauthorised access to an account or system.

Methods for two-factor authentication

Two-factor authentication can be implemented in different ways depending on the service and the chosen security method. One of the most common methods is One-Time Passwords (OTP), where a temporary code is sent via SMS, email or an authenticator app like Google Authenticator. Another popular solution is physical security keys, such as YubiKey, which connect via USB, NFC or Bluetooth to verify the user's identity.

Some systems use biometric authentication, where login is authorised via fingerprint, facial recognition or iris scan. Another method is push notifications, where the user receives a notification on a trusted device and must actively authorise the login attempt. As an additional security measure, backup codes can also be used, which are pre-generated one-time codes that can be used if the primary 2FA method is not available.

These different methods ensure that even if a hacker gets hold of a password, an additional verification is still required to access the account.

Benefits of two-factor authentication

Two-factor authentication significantly improves account security, here are some of the benefits:

• Increased security: Makes it much harder for hackers to access accounts, even if a password is compromised.
• Protects against phishing and data breaches: Even if a hacker gains access to a password via phishing or a data breach, they will still lack the second factor.
• Flexible authentication methods: Users can choose between different methods such as SMS, apps or biometric authentication.
• Wide adoption: Supported by most major services like Google, Facebook, Microsoft and online banking.

Application areas for two-factor authentication

Two-factor authentication is used in many different contexts to protect sensitive data and prevent unauthorised access. Online banks and financial institutions often require 2FA for transactions to prevent financial fraud. Email and social media support 2FA to protect user accounts from hacking and identity theft. Businesses and governments implement 2FA to secure access to internal systems and protect sensitive data.

Cryptocurrency exchanges and cloud services also use 2FA to protect user accounts where access to digital assets can have major financial consequences. With cyber threats on the rise, 2FA is becoming an increasingly necessary part of IT security.

FAQ - Frequently asked questions