käyttäjäntunnistus

Käyttäjäntunnistus, known in English as user authentication, is a process that verifies the identity of a user attempting to access a system or resource. This verification is crucial for security, ensuring that only authorized individuals gain access to sensitive information or functionalities. The fundamental goal of user authentication is to confirm that a user is who they claim to be.

There are several common methods for user authentication. One of the most widespread is the use of a username and password. In this model, the user provides a unique identifier (username) and a secret code (password) that the system compares against its records. Another prevalent method involves multi-factor authentication (MFA), which requires users to provide two or more pieces of evidence to prove their identity. This can include something the user knows (like a password), something the user has (like a mobile phone for a one-time code), or something the user is (like a fingerprint or facial scan). Biometric authentication, utilizing unique biological characteristics, is becoming increasingly common for its convenience and perceived security. Other methods include token-based authentication, where a physical or digital token is used, and certificate-based authentication, which relies on digital certificates issued by a trusted authority. The choice of authentication method often depends on the security requirements of the system and the desired user experience.