# NIST SP 800-53 Rev. 5 SC-3(1) — Hardware Separation

- Source: https://support.icompaas.com/compliance/nist-sp-800-53-rev-5/sc-3-1-hardware-separation
- Section: [Compliance](https://support.icompaas.com/compliance) › [NIST SP 800-53 Rev. 5 Controls](https://support.icompaas.com/compliance/nist-sp-800-53-rev-5) › SC — System and Communications Protection
- Last updated: 2026-06-05
- Publisher: iCompaas, Inc. (https://www.icompaas.com)

**NIST SP 800-53 Rev. 5**·Control `SC-3(1)`·high·Component: **System and Communications Protection**

## What this control requires

> Employ hardware separation mechanisms to isolate security functions. Use microprocessor-based ring architectures and hardware-enforced address segmentation to support distinct storage objects with separate access attributes. This control supports the Hardware-Enforced Isolation Framework capability within the System and Communications Protection family.
> 
> — NIST SP 800-53 Rev. 5, Control SC-3(1)

### In plain English

Employ hardware separation mechanisms to isolate security functions. In practice, this means you can prove you policy management-level controls on a defined cadence.

## Why it matters

SP 800-53 is the catalogue every U.S. federal authorisation (FedRAMP, FISMA, CMMC) and most regulated industries point at. A missing control surfaces as a Plan of Action & Milestones (POA&M) item that an Authorizing Official must approve before the Authority To Operate is granted or renewed.

This control is rated **high**. Auditors expect a named owner, a remediation SLA, and a tooling artefact that evidences continuous operation.

## What an auditor looks for

A 3PAO (FedRAMP) or Independent Assessor (NIST RMF) tests against NIST SP 800-53A assessment procedures. For each control they expect a documented implementation that addresses every assessment objective (Examine, Interview, Test) and an implementation summary in the System Security Plan.

Within **System and Communications Protection**, the assessor will trace your implementation back to the catalogue reference (Control SC-3(1)) and look for objective evidence on the latest two assessment cycles.

## How to implement

#### Policy Management

**Docs.** Keep each policy in version-controlled Markdown alongside the code that implements it; ship a signed PDF snapshot at each annual review and link the SHA into the SoA.

### Operational checklist

-   **Policy.** Document the trigger, the owner and the cadence.
-   **Access.** Document the trigger, the owner and the cadence.
-   **Security.** Document the trigger, the owner and the cadence.
-   **Separation.** Document the trigger, the owner and the cadence.
-   **Network.** Document the trigger, the owner and the cadence.
-   **Scope:** management, attributes, system, functions, protection, hardware, capability, storage.

## Evidence to collect

-   **Policy Document.** A signed and version-controlled policy / standard / procedure document.

Signed policy or standard documents the safeguard. Focus: Hardware Separation.

## Common pitfalls

-   Policies that no engineer has read; the version in Confluence drifts from the version that's actually being enforced.

## How it maps to other frameworks

Computed from shared tags, control component and key-operation subjects — handy when you are reconciling controls across an audit.

-   [**NIST SP 800-171 Rev. 3 3.14.3** — Security Alerts, Advisories, and Directives](https://support.icompaas.com/compliance/nist-sp-800-171-rev-3/3-14-3-security-alerts-advisories-and-directives)
-   [**HIPAA (45 CFR Part 164) 164.308(a)(5)(i)** — Security Awareness and Training](https://support.icompaas.com/compliance/hipaa/164-308-a-5-i-security-awareness-and-training)
-   [**BSI C5:2020 SP-01** — Documentation, communication and provision of policies and instructions](https://support.icompaas.com/compliance/bsi-c5-2020/sp-01-documentation-communication-and-provision-of-policies-and-instructions)

## Related controls in NIST SP 800-53 Rev. 5

-   [**Control SC-16(2)** — Anti-Spoofing Mechanisms](https://support.icompaas.com/compliance/nist-sp-800-53-rev-5/sc-16-2-anti-spoofing-mechanisms)
-   [**Control SC-39(1)** — Hardware Separation](https://support.icompaas.com/compliance/nist-sp-800-53-rev-5/sc-39-1-hardware-separation)
-   [**Control SC-49** — Hardware-Enforced Separation And Policy Enforcement](https://support.icompaas.com/compliance/nist-sp-800-53-rev-5/sc-49-hardware-enforced-separation-and-policy-enforcement)
-   [**Control SC-3(5)** — Layered Structures](https://support.icompaas.com/compliance/nist-sp-800-53-rev-5/sc-3-5-layered-structures)
-   [**Control SC-3(4)** — Module Coupling And Cohesiveness](https://support.icompaas.com/compliance/nist-sp-800-53-rev-5/sc-3-4-module-coupling-and-cohesiveness)
-   [**Control SC-39(2)** — Separate Execution Domain Per Thread](https://support.icompaas.com/compliance/nist-sp-800-53-rev-5/sc-39-2-separate-execution-domain-per-thread)

## References

-   [NIST Computer Security Resource Center — NIST SP 800-53 Rev. 5](https://csrc.nist.gov/Projects/risk-management/sp800-53-controls)
-   Catalogue identifier: `Control SC-3(1)`

Topics: governance risknetwork segmentationpolicy management

## Related compliance guidance

- [NIST SP 800-53 Rev. 5: a practical implementation guide for cloud teams](https://support.icompaas.com/compliance/nist-sp-800-53-rev-5): Start with the full NIST SP 800-53 implementation guide — scope, roadmap, evidence and how the assessment runs.
- [NIST SP 800-171 and CMMC: a practical guide to protecting CUI in the cloud](https://support.icompaas.com/compliance/nist-sp-800-171-rev-3): If your obligation is protecting CUI in your own systems for a federal or defence contract, this derived subset — not the full catalogue — is the requirement.
- [SOC 2 compliance: a practical implementation guide for cloud-native SaaS teams](https://support.icompaas.com/compliance/soc-2-trust-services-criteria): Most commercial SaaS already hold a SOC 2 Type 2, and FedRAMP 20x Class A is designed for providers that have one.
