Policy Enforcement Point: How It Works in Zero Trust

The key role of a Policy Enforcement Point (PEP) can be understood by comparing it to a doorman at a party: he only lets you in if you’re on the guest list. It is a key component within Zero Trust architectures, where it is responsible for turning security policies into actual controls. 

 

With the proliferation of non-human identities, the uncontrolled expansion of the cloud, and distributed environments, the PEP is equivalent to stationing a guard at every door, rather than relying on perimeter-based security measures that no longer work.

 

This is an operational requirement at a time when the NSA continues to highlight deficiencies in access policies as one of the main entry points for cyber threats.

Therefore, below we share a guide on exactly how a Policy Enforcement Point works in hybrid and cloud environments, examples of where to place it, and some mistakes to avoid.

How a Policy Enforcement Point Functions as a Control Point in Hybrid and Cloud Architectures

Understanding how a Policy Enforcement Point works in theory is simple: it intercepts requests for access to a resource and determines whether to grant or deny access. In hybrid and cloud environments, Policy Enforcement Points must be located anywhere that could serve as an open door to the systems or information in a digital environment.

To perform this task, PEPs work in a sort of team with other components:

• Of particular note is the role of the PDP (Policy Decision Point), which is responsible for analyzing requests, deciding whether to grant or deny access, and communicating the decision to the PEP.
• Other components include the PAP (which manages access policies), the PIP (which provides additional information on the attributes needed for the PDP to make decisions), and the PRP (which stores access authorization policies).

In practice, the Policy Enforcement Point operates as follows:

• It all begins when someone (or something—that is, a non-human entity) attempts to access a resource. The Policy Enforcement Point intercepts the request when it “knocks on the door,” before it can open it. 
• The PEP translates the request into XACML and sends it to the Policy Decision Point, which evaluates whether that action should be allowed.
• The PDP consults the policies to be applied via the PRP, which are managed by the PAP. If it needs additional context (e.g., which device is connecting from? What is the data’s sensitivity classification?), it can consult the PIPs.
• With all the information on the table, the PDP issues its verdict: allow or deny access—and in cases where the policy does not cover the situation or there is an evaluation error, it returns exception states that the PEP must handle securely. The decision is then returned to the PEP, which ultimately determines whether to open the door or keep it closed. 

Examples of Policy Enforcement Point locations in companies that protect every access point

• PEPs on web pages, installed on gateways and proxies, among other locations.
• Role-based PEPs located at various login points (for example, at entry points to corporate applications).
• PEPs for dynamic roles, which evaluate whether users have an authorized role, in addition to complying with the specific XACML rule.
• External PEPs.
• PEPs in password vaults, thereby protecting access to credential storage tools. 

When Controls Fail: Common Mistakes in PEP Implementation

• Applying generic policies with the same rules for all accesses and data types without considering their sensitivity or compliance requirements.
• Fragmented management, resulting in policies that exist in silos disconnected from one another.
• Setting rules and configurations but failing to update them in response to new threats or security requirements.
• Failing to test or validate Policy Enforcement Points to verify that access decisions are functioning correctly.

Avoiding these mistakes requires a platform capable of centrally orchestrating identity policies and consistently enforcing them at every PEP, thereby making Zero Trust a reality.

Soffid AM integrates Policy Enforcement Point management into a converged architecture with IGA and PAM—so that policies aren’t just on paper, but are controls that operate at every access point, in real time.

Want to see how this works in your environment? Tell us about your architecture, and we’ll show you how Soffid enforces access control in practice. Contact our team.