Tunnistautumistekijä

Tunnistautumistekijä, often translated as authentication factor, is a piece of information or a credential used to verify a person's identity when accessing a system or service. It is a fundamental component of authentication protocols and security systems. The purpose of using an authentication factor is to ensure that only authorized individuals can gain access, preventing unauthorized use and protecting sensitive data.

There are generally three categories of authentication factors. The first is something you know, which includes passwords, PINs, or answers to security questions. The second is something you have, such as a physical token, a smartphone receiving a one-time code, or a smart card. The third is something you are, which refers to biometric characteristics like fingerprints, facial recognition, or iris scans.

To enhance security, systems often employ multi-factor authentication (MFA). MFA requires the user to present two or more authentication factors from different categories. For example, entering a password (something you know) and then confirming a code sent to your phone (something you have) is a common form of MFA. This layered approach significantly increases the difficulty for attackers to compromise an account, as they would need to obtain multiple, distinct types of credentials. The choice and combination of authentication factors depend on the security requirements of the system and the desired user experience.