Understanding IA.L1-3.5.1 (Identification and Authentication Requirements)
TheCMMC 2.0 Level 1practiceIA.L1-3.5.1aligns withNIST SP 800-171, Requirement 3.5.1, which mandates that organizationsidentify system users, processes acting on behalf of users, and devicesto ensure proper access control.
To comply with this requirement, anOrganization Seeking Certification (OSC)must maintain documentation that demonstrates:
A unique identifier (username) for each system user
Mapping of system accounts to specific individuals
Identification of devices and automated processes that access systems
Why " C. User names associated with system accounts assigned to those individuals " is Correct?
This documentation directly satisfies IA.L1-3.5.1because it showshow system users are uniquely identified and linked to specific accountswithin the environment.
Alist of users and their assigned accountsconfirms that the organization has a structured method oftracking access and authentication.
It allows auditors to verify thateach user has a distinct identityand that access control mechanisms are properly applied.
Why Other Answers Are Incorrect?
A. Procedures for implementing access control lists (Incorrect)
While access control lists (ACLs) are relevant for authorization, they do notidentify users or devicesspecifically, making them insufficient as primary evidence for IA.L1-3.5.1.
B. List of unauthorized users that identifies their identities and roles (Incorrect)
Identifying unauthorized users does not fulfill the requirement of trackingauthorizedusers, devices, and processes.
D. Physical access policy stating " All non-employees must wear a special visitor pass or be escorted " (Incorrect)
This pertains tophysical security, not system-baseduser identification and authentication.
Conclusion
The correct answer isC. User names associated with system accounts assigned to those individuals, as thisdirectly satisfies the identification requirement of IA.L1-3.5.1.
[References:, CMMC 2.0 Level 1 Practice IA.L1-3.5.1, NIST SP 800-171, Requirement 3.5.1, , , ]
