Protecting CUI isn’t getting any easier, and providers in the DIB are looking for ways to protect sensitive data above and beyond network and app security.  One such method gaining prominence is the implementation of CMMC-compliant enclaves. Enclaves are logical or physical isolation zones engineered to meet the requirements of CMMC, particularly for Levels 2 and 3. 

This blog delves into the concept, design, implementation, and strategic value of CMMC-compliant enclaves. It focuses on their role in achieving certification, reducing assessment scope, and managing compliance risk, empowering you with the knowledge to make strategic decisions.

Understanding the CMMC Context

The CMMC framework establishes three certification levels:

• Level 1 focuses on basic safeguarding and includes 15 requirements drawn from FAR 52.204-21. These are designed to protect FCI and represent the minimum cybersecurity hygiene expected of contractors. 
• Level 2 incorporates all 110 controls from NIST SP 800-171, requiring a more robust and systematic cybersecurity posture to protect CUI. 
• Level 3 builds upon Level 2 by incorporating selected practices from NIST SP 800-172, providing enhanced security against Advanced Persistent Threats (APTs).

While Level 1 can be addressed through enterprise-wide improvements, Levels 2 and 3 often require more targeted approaches that can be solved with enclaves.

What Is a CMMC-Compliant Enclave?

A CMMC-compliant enclave is a dedicated and secure area, either created through technology like VLANs and firewalls or physically separated, where all necessary CMMC controls are fully implemented. These enclaves are specifically designed to handle CUI and maintain compliance with Level 2 or Level 3 requirements.

Per CMMC Assessment and Scoping Guides, a well-structured enclave must:

• Encompass all systems and assets that process, store, or transmit CUI.
• Operate independently from the rest of the enterprise network.
• Implement comprehensive boundary controls and enforce strict access restrictions.

By focusing security controls within a defined perimeter, organizations can strategically limit the scope of their CMMC assessments, simplifying compliance efforts.

Why Build an Enclave? 

Implementing an enclave isn’t just a compliance shortcut-it’s a strategic move that brings tangible business and security benefits, reassuring you of the soundness of your decision.

Implementing an enclave is a strategic move that brings tangible business and security benefits:

• First, it allows for scope reduction. Instead of applying all 110+ security controls enterprise-wide, organizations can use them only to systems and users within the enclave. This significantly simplifies the assessment process and reduces compliance overhead. 
• Next is cost control. With fewer systems and users in scope, the costs associated with implementing, documenting, and assessing cybersecurity controls are significantly reduced. 
• Enclaves help mitigate risk. If a security incident occurs, the damage can be confined within the enclave, protecting the broader organization. 
• Lastly, enclaves lead to assessment efficiency. Clear boundaries and focused controls enable C3PAOs and DCMA DIBCAC assessors to more easily evaluate your environment, resulting in smoother audits and faster certifications.

How to Build the Right Enclave

Designing a compliant enclave is a complex and enterprise-level initiative that requires meticulous planning and execution. The process begins with identifying all assets that process, store, or transmit CUI. This inventory becomes the foundation for your enclave.

From there, you must determine how to segment these assets. Logical segmentation (such as VLANs and firewall rules) may suffice for some, while others will require physical separation or isolated virtual environments. Access control is another critical piece—enclaves should employ multifactor authentication, strict role-based access, and robust session management to limit entry points.

Every enclave must be supported by a System Security Plan (SSP). This plan should clearly describe the enclave’s boundaries, the controls in place, how CUI flows through the environment, and any external systems it interfaces with.

You’ll also need to consider how data moves in and out of the enclave. Data flow must be tightly controlled and encrypted, both in transit and at rest. Logging, alerting, and response mechanisms should be enclave-specific and capable of rapidly detecting and mitigating threats.

Practical Use Cases of CMMC-Compliant Enclaves

CMMC-compliant enclaves are versatile and can be adapted to fit various organizational contexts, inspiring you with the potential of this strategy.

For example, a small defense contractor could create an enclave within their existing network to handle CUI. At the same time, a larger organization might establish a physically separate enclave for its CUI-handling systems. For SMBs, enclaves provide a cost-effective path to compliance. Rather than trying to retrofit an entire IT environment, SMBs can isolate their CUI-handling systems and secure only what’s necessary.

In agency/subcontractor collaborations, enclaves facilitate secure cooperation without requiring full network integration. Each party maintains its own compliant environment while still contributing to the larger project.

For organizations operating in multi-tenant or cloud environments, enclaves can be established using FedRAMP High or DoD IL4 or IL5 cloud services, enabling compliant operations within shared infrastructures.

Challenges in Implementing CMMC Enclaves

While the benefits of enclaves are substantial, they come with their own set of challenges. A common pitfall is improper scoping, which occurs when all assets that handle CUI are not included. This oversight can result in failed assessments and necessitate costly rework.

Another risk is inadequate documentation. A vague or outdated SSP, or a poorly defined enclave boundary, can derail even the most technically sound implementations.

There’s also the danger of over-segmentation. While isolation is key, excessive separation can create operational silos, increase costs, and slow down workflows.

Finally, enclaves rarely operate in complete isolation. They often need to interact with enterprise services, third-party tools, or external partners. Poorly managed interfaces can become compliance liabilities.

Strategic Recommendations for Implementing CMMC Enclaves

To maximize the effectiveness of your enclave strategy, begin with a thorough understanding of your CUI environment.

• Map out where CUI is stored, processed, and transmitted, and define the smallest viable scope for your enclave.
• Next, leverage existing security frameworks. Use NIST SP 800-171 and 800-172 as foundational references, and align your design with FedRAMP, ISO 27001, or other trusted frameworks to streamline compliance.
• Tailor your policies and procedures to the enclave. Avoid relying on enterprise-wide standards that may not apply. Instead, create documentation that reflects the specific configurations and risks of your enclave.
• Engage with qualified assessors early in the process to ensure a smooth evaluation. RPOs and C3PAOs can provide critical insights before you invest significant time and resources.
• Lastly, plan for scalability. Your enclave should not only meet current compliance needs but also be flexible enough to adapt to future regulatory changes or business growth.

Understand How Enclaves Can Fit CMMC Compliance with Continuum GRC

As CMMC becomes a contractual requirement across the DIB, enclaves offer a strategic pathway for organizations to achieve and sustain compliance. By isolating CUI within well-controlled boundaries, companies can reduce risk, streamline assessments, and ensure the security of sensitive government data.

We provide risk management and compliance support for every major regulation and compliance framework on the market, including:

• FedRAMP
• StateRAMP
• GDPR
• NIST 800-53
• FARS NIST 800-171
• CMMC
• SOC 1, SOC 2
• HIPAA
• PCI DSS 4.0
• IRS 1075
• COSO SOX
• ISO 27000 Series
• ISO 9000 Series
  
• ISO Assessment and Audit Standards

And more. We are the only FedRAMP and StateRAMP-authorized compliance and risk management solution worldwide.

Continuum GRC is a proactive cybersecurity® and the only FedRAMP and StateRAMP-authorized cybersecurity audit platform worldwide. Call 1-888-896-6207 to discuss your organization’s cybersecurity needs and learn how we can help protect your systems and ensure compliance.