Evaluating access control systems: From DAC to PBAC

June 5, 2023

I-phone touching up to key-pad thumbnail image

In today’s rapidly evolving cyber-physical landscape, securing access to sensitive information and resources is vital to the health of just about any organization. One crucial aspect of securing systems is implementing effective access control mechanisms. Discretionary Access Control (DAC) is an access control model that enables organizations to define and enforce permissions based on individual user discretion. But what is it and how does it differ from Policy-Based Access Control (PBAC)? Don’t worry—you’ll know more in minutes.

Understanding Discretionary Access Control (DAC)

In the context of physical security, DAC plays a vital role in safeguarding cyber-physical systems. By implementing DAC, organizations can regulate access to critical infrastructure, ensuring that only authorized personnel can interact with these systems. For instance, in an industrial facility, DAC can be applied to control access to sensitive machinery or operational control systems, preventing unauthorized individuals from tampering with or disrupting crucial processes.

The principle of least privilege is a fundamental concept in DAC that promotes the idea of granting users only the minimum level of access necessary to perform their tasks. By adhering to this principle, organizations can minimize the potential damage caused by accidental or intentional misuse of privileges. In a cyber-physical environment, this ensures that individuals can access only the specific components they need for their job, reducing the attack surface and preventing unauthorized alterations.

Enhancing access control with Policy-Based Access Control (PBAC)

While DAC provides a flexible framework for access control, it may not always suffice for complex security requirements. This is where PBAC comes into play. PBAC is an access control model that uses policies to define access rights based on various attributes and conditions. By leveraging PBAC, organizations can implement more sophisticated access control mechanisms that align with their specific security needs.

In a PBAC system, security policies define the conditions under which access is granted or denied. These policies take into account attributes such as user roles, time of access, location and the sensitivity of the resource being accessed. PBAC can complement DAC by enabling organizations to enforce granular access control policies that align with their specific security requirements.

In a cyber-physical environment, PBAC helps establish comprehensive security policies by considering not only the users and their permissions but also the contextual factors that may impact access decisions. For example, in a high-security facility, a PBAC policy might dictate that access to certain areas is restricted to specific individuals during certain times, even if they possess the necessary DAC permissions. PBAC adds an extra layer of security and ensures that access control decisions align with the organization’s overall security objectives.

PBAC also facilitates dynamic access control, allowing organizations to adapt access permissions in real-time based on changing conditions or evolving threats. This capability is particularly crucial in cyber-physical systems, where the physical environment and associated risks can fluctuate rapidly. By combining DAC with PBAC, organizations can establish a robust and adaptive access control system that addresses the complex security challenges presented by cyber-physical environments.

Putting it all together

Implementing robust access control mechanisms is a must for maintaining the security of cyber-physical systems. Discretionary Access Control (DAC) provides individuals with control over their resources, allowing them to determine access permissions through Access Control Lists (ACLs). In physical security, DAC plays a critical role in granting authorized personnel access to sensitive infrastructure while preventing unauthorized access. Plus, the integration of Policy-Based Access Control (PBAC) further enhances access control mechanisms by enabling organizations to define security policies based on contextual factors. By leveraging DAC and PBAC, organizations can establish a comprehensive access control system that balances individual discretion, centralized administration and dynamic security policies, ensuring the protection of cyber-physical systems and minimizing vulnerabilities.

Contact Alert Enterprise and we’ll show you how to control access according to individual schedules and specifications with the first-ever Policy-Based Access Control cloud service.

Let's chat.