Kertakäyttökoodit

Kertakäyttökoodit, sometimes referred to as one-time passwords or OTPs, are a crucial security mechanism in modern digital authentication. These codes are designed to be used only once, significantly enhancing the security of user accounts and sensitive transactions. Unlike static passwords that remain the same over time, a kertakäyttökoodi is generated dynamically and expires shortly after its creation. This temporary nature makes them highly resistant to replay attacks, where an attacker attempts to reuse a previously intercepted authentication code.

Kertakäyttökoodit are commonly employed as a second factor in multi-factor authentication (MFA) systems. This means that in addition to a user's primary password, they must also provide a valid kertakäyttökoodi to gain access. This layered approach dramatically increases the difficulty for unauthorized individuals to compromise an account, even if they manage to obtain the user's password.

The generation of kertakäyttökoodit typically relies on cryptographic algorithms. Two primary methods are time-based (TOTP) and event-based (HOTP). TOTP codes change at regular intervals, usually every 30 or 60 seconds, synchronized between the server and the user's authentication device, such as a smartphone app or a dedicated hardware token. HOTP codes, on the other hand, are generated sequentially and are tied to an event counter. The user or the server increments the counter with each new code. Kertakäyttökoodit are a vital component in safeguarding online interactions and protecting personal data.