Understanding Access Control in CMMC

Access control refers to the process ofgranting or denyingspecific requests to:

Obtain and use information

Access information processing services

Enter specific physical locations

TheAccess Control (AC) domain in CMMCis based onNIST SP 800-171 (3.1 Access Control family)and includes requirements to:

✅Implement policies for granting and revoking access.

✅Restrict access to authorized personnel only.

✅Protect physical and digital assets from unauthorized access.

Since the questionbroadly asks about the process of granting or denying access to information, services, and physical locations, the correct answer isA. Access Control.

Why the Other Answers Are Incorrect

B. Physical access control

❌Incorrect.Physical access controlis asubsetof access control that only applies tophysical locations(e.g., keycards, security guards, biometrics). The question includesinformation and services, makinggeneral access controlthe correct choice.

C. Mandatory access control (MAC)

❌Incorrect.MAC is a specific type of access controlwhere access is strictly enforced based onsecurity classifications(e.g., Top Secret, Secret, Confidential). The questiondoes not specify MAC, so this is incorrect.

D. Discretionary access control (DAC)

❌Incorrect.DAC is another specific type of access control, whereownersof data decide who can access it. The question asksgenerallyabout granting/denying access, makingaccess control (A)the best answer.

CMMC Official References

CMMC 2.0 Model - AC.L2-3.1.1 to AC.L2-3.1.22– Covers access control requirements, includingcontrolling access to information, services, and physical spaces.

NIST SP 800-171 (3.1 - Access Control Family)– Defines the general principles of access control.

Thus,option A (Access Control) is the correct answer, as it best aligns withCMMC access control requirements.