The primary purpose of multi-factor authentication (MFA) is to enhance security by creating a layered defense. It requires a user to provide two or more distinct verification factors (e.g., something you know, something you have, something you are) to gain access to a resource. By requiring multiple credentials, MFA ensures that even if one factor, such as a password, is compromised, an unauthorized user still cannot gain access. This is especially critical in cloud environments where resources are accessible over public networks, making them a prime target for credential theft and unauthorized access attempts.

B. To simplify the authentication process:

MFA inherently adds steps to the login process, making it more complex, not simpler, than single-factor authentication.

C. To reduce costs:

Implementing MFA solutions typically involves initial and ongoing costs. Its primary goal is security enhancement, not direct cost reduction.

D. To improve performance:

The additional verification steps in MFA introduce a slight latency to the authentication process, which does not improve system performance.

1. Cisco Official Documentation: In the "What Is Multi-Factor Authentication (MFA)?" guide for Cisco Duo, it is stated: "MFA adds an additional layer of security, making it harder for unauthorized users to gain access to a device or network... A password alone is not enough to protect valuable company assets."

Source: Cisco, "What Is Multi-Factor Authentication (MFA)?" Cisco.com.

Reference: Accessed under the "How Does MFA Work?" section, Paragraph 1.

2. Peer-reviewed Academic/Standards Publication: The National Institute of Standards and Technology (NIST) Special Publication 800-63B outlines digital identity guidelines. It explicitly defines MFA as a method to achieve a higher assurance level of authentication than single-factor methods.

Source: NIST Special Publication 800-63B, "Digital Identity Guidelines: Authentication and Lifecycle Management."

Reference: Section 5.1.3, "Multi-Factor Authentication (MFA)," Page 18.

3. University Courseware: Course materials from reputable computer science programs consistently describe MFA as a mechanism to bolster security against the weaknesses of single-factor (password-based) systems.

Source: MIT OpenCourseWare, 6.857 Computer and Network Security, Fall 2014.

Reference: Lecture 15 Notes, "Authentication," Section 3, which discusses the progression from passwords to stronger two-factor authentication to mitigate security risks.