AC	Access Control
IoT	Internet of Things
HEAD	Hierarchical, Extensible, Advanced, and Dynamic
DAC	Discretionary Access Control Model
MAC	Mandatory Access Control Model
RBAC	Role-based Access Control Model
ABAC	Attribute-based Access Control Model
IS	Information System
HGABAC	Hierarchical Group and Attribute-based Access Control
HoBAC	Higher-order Attribute-based Access Control
CBAC	Category-based Access Control
CSPM	Cloud Security and Privacy Metamodel
WCMS	Web Content Management System
E${}_{\mathrm{x}}$	Explicit
I${}_{\mathrm{m}}$	Implicit
AU	Authorization Unit
PU	Procedural Unit
S${}_{\mathrm{t}}$	Setting