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Review on Multi-Factor Authentication (MFA) Sources and Operation Challenges

In recent years, with the mushrooming of internet-enabled mobile devices, there has been a corresponding increase in information and data being transmitted and received. This development has raised concerns about security and one of the crucial components associated with it: authentication. With a wide variety of services and communication being executed online nowadays, user authentication has come to encompass diverse fields, from online bill payments, management of entry, or access rights to vital correspondence, and much more. This paper looks at what authentication is and traces its checkered evolution, from its earliest simple single-factor version, then growing into two-factor mode and finally morphing into multi-factor (MFA) authentication. Now MFA, incorporating biometrics, is gaining widespread acceptance across numerous fields, mainly because it is dependable, quick, user-friendly, and ensures advanced safety and security. This paper, in addition to reviewing some sophisticated and potential MFA sources, also briefly dwells on the different ways MFA is being integrated.