Mandatory Access Control
Media Access Control
Medium Access Control
message authentication code
Message Authentication Code
Mission Assurance Category
Modification, Access, and Creation

  A means of restricting access to objects based on the sensitivity (as represented by a security label) of the information contained in the objects and the formal authorization (i.e., clearance, formal access approvals, and need-to-know) of subjects to access information of such sensitivity. Mandatory Access Control is a type of nondiscretionary access control.
Source(s):
NIST SP 800-53 Rev. 4 under Mandatory Access Control CNSSI 4009

  An access control policy that is uniformly enforced across all subjects and objects within the boundary of an information system. A subject that has been granted access to information is constrained from doing any of the following: (i) passing the information to unauthorized subjects or objects; (ii) granting its privileges to other subjects; (iii) changing one or more security attributes on subjects, objects, the information system, or system components; (iv) choosing the security attributes to be associated with newly-created or modified objects; or (v) changing the rules governing access control. Organization-defined subjects may explicitly be granted organization-defined privileges (i.e., they are trusted subjects) such that they are not limited by some or all of the above constraints.
Source(s):
NIST SP 800-53 Rev. 4 under Mandatory Access Control

  Message Authentication Code.
Source(s):
NIST SP 800-108
NIST SP 800-185
NIST SP 800-56C [Superseded]

  a data authenticator generated from the message, usually through cryptographic techniques. In general, a cryptographic key is also required as an input.
Source(s):
NIST SP 800-15 under message authentication code

  A means of restricting access to system resources based on the sensitivity (as represented by a label) of the information contained in the system resource and the formal authorization (i.e., clearance) of users to access information of such sensitivity.
Source(s):
NIST SP 800-44 Version 2 under Mandatory Access Control

  A cryptographic checksum on data that uses a symmetric key to detect both accidental and intentional modifications of the data.
Source(s):
NISTIR 7711 under Message Authentication Code