Access control models (MAC, DAC, ABAC) in Cybersecurity - Step-by-Step Execution

Concept Flow - Access control models (MAC, DAC, ABAC)

User Requests Access

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Check Access Control Model

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MAC

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Access Granted or Denied Based on Model Rules

When a user requests access, the system checks which model applies (MAC, DAC, or ABAC) and then decides access based on rules, ownership, or attributes.

Execution Sample

Cybersecurity

User requests file access
System checks MAC labels
System checks DAC ownership
System checks ABAC attributes
System grants or denies access

This sequence shows how a system processes an access request using MAC, DAC, and ABAC models.

Analysis Table

Step	Access Control Model	Check Performed	Condition	Access Decision
1	MAC	Check user and object security labels	User label >= Object label	Access Granted
2	MAC	Check user and object security labels	User label < Object label	Access Denied
3	DAC	Check if user is owner or has permission	User is owner or permission granted	Access Granted
4	DAC	Check if user is owner or has permission	User is not owner and no permission	Access Denied
5	ABAC	Evaluate user, resource, environment attributes	Attributes satisfy policy rules	Access Granted
6	ABAC	Evaluate user, resource, environment attributes	Attributes do not satisfy policy rules	Access Denied

💡 Access decision made based on model-specific checks and conditions.

State Tracker

Variable	Start	After Step 1	After Step 3	After Step 5	Final
User Label	Low	Low	Low	Low	Low
Object Label	Medium	Medium	Medium	Medium	Medium
User Ownership	No	No	Yes	Yes	Yes
User Attributes	Role=User	Role=User	Role=User	Role=Admin	Role=Admin
Access Decision	None	Denied	Granted	Granted	Granted

Key Insights - 3 Insights

Why does MAC deny access when user label is lower than object label?

Because MAC enforces strict rules based on security labels; if the user's clearance is lower than the object's classification, access is denied as shown in execution_table step 2.

How does DAC differ in deciding access compared to MAC?

DAC bases access on ownership and permissions set by the owner, not on fixed labels. As seen in steps 3 and 4, if the user owns the resource or has permission, access is granted.

What makes ABAC more flexible than MAC and DAC?

ABAC uses multiple attributes (user role, time, location) to decide access dynamically, allowing complex policies as shown in steps 5 and 6.

Visual Quiz - 3 Questions

Look at the execution_table, at which step does MAC deny access?

A Step 1

B Step 2

C Step 3

D Step 5

💡 Hint

Check the 'Access Decision' column for MAC model steps.

According to variable_tracker, what is the User Ownership after Step 3?

A Yes

B Unknown

C No

D Low

💡 Hint

Look at the 'User Ownership' row under 'After Step 3' column.

If the user attributes change to Role=Guest, how would ABAC's access decision change in execution_table?

A No change in access decision

B Access Granted at Step 5

C Access Denied at Step 6

D Access Granted at Step 3

💡 Hint

Refer to ABAC steps 5 and 6 where attributes affect access.

Concept Snapshot

Access Control Models:
- MAC: System-enforced, based on security labels.
- DAC: Owner-controlled, based on permissions.
- ABAC: Attribute-based, flexible policies using user/resource/environment attributes.
Access is granted or denied by checking these rules when a user requests access.

Full Transcript

Access control models determine how systems decide if a user can access a resource. Mandatory Access Control (MAC) uses fixed security labels and strict rules, denying access if the user's clearance is lower than the object's classification. Discretionary Access Control (DAC) lets resource owners decide who can access their resources, granting access if the user is the owner or has permission. Attribute-Based Access Control (ABAC) uses multiple attributes like user role, resource type, and environment conditions to make flexible access decisions. When a user requests access, the system checks the relevant model's rules and grants or denies access accordingly.