# SC-31(3)_measure-bandwidth-in-operational-environments

> Measure the bandwidth of [organization-defined] in the operational environment of the system.

- Skill: `cyberstrikeus/sc-31-3-measure-bandwidth-in-operational-environments` (Agent Skill)
- Install (CLI): `npx skillmds@latest add cyberstrikeus/sc-31-3-measure-bandwidth-in-operational-environments`
- Raw SKILL.md: https://api.skillmd.com/api/skills/cyberstrikeus/sc-31-3-measure-bandwidth-in-operational-environments/raw
- Safety review: PASS (external: skill-scanner PASS, skillspector PASS)
- Works with: Claude Code, Claude.ai, OpenAI Codex
- Category: Coding & Dev Tools
- Author: cyberstrikeus (https://skillmd.com/u/cyberstrikeus)
- Updated: 2026-09-17
- Page: https://skillmd.com/skills/cyberstrikeus/sc-31-3-measure-bandwidth-in-operational-environments

---


# SC-31(3) Measure Bandwidth in Operational Environments

> **Enhancement of:** SC-31

## High-Level Description

**Family:** System and Communications Protection (SC)
**Framework:** NIST SP 800-53 Rev 5

Measuring covert channel bandwidth in specified operational environments helps organizations determine how much information can be covertly leaked before such leakage adversely affects mission or business functions. Covert channel bandwidth may be significantly different when measured in settings that are independent of the specific environments of operation, including laboratories or system development environments.

## What to Check

- [ ] Verify SC-31(3) Measure Bandwidth in Operational Environments is documented in SSP
- [ ] Confirm control is operating effectively
- [ ] Review evidence of continuous monitoring for SC-31(3)
- [ ] Verify enhancement builds upon base control SC-31

## How to Test

### Step 1: Review Documentation

Examine the System Security Plan (SSP) and related artifacts for SC-31(3) implementation details. Verify the organization has documented how this control is satisfied.

### Step 2: Validate Implementation

```
# For cloud environments, use cloud-audit-mcp tools
# For on-premises, review system configurations directly

# Example: Check if account management policies exist
grep -r "account.management\|access.control" /etc/security/ 2>/dev/null
```

### Step 3: Test Operating Effectiveness

Verify the control is actively functioning, not just documented. Check logs, configurations, and operational evidence.

## Tools

| Tool            | Purpose                               | Usage                                |
| --------------- | ------------------------------------- | ------------------------------------ |
| cloud-audit-mcp | Check encryption and network controls | `cloud_audit_encryption`             |
| nmap            | Network scanning                      | `nmap -sV --script ssl-enum-ciphers` |

## Remediation Guide

### Control Statement

Measure the bandwidth of [organization-defined] in the operational environment of the system.

### Implementation Guidance

Measuring covert channel bandwidth in specified operational environments helps organizations determine how much information can be covertly leaked before such leakage adversely affects mission or business functions. Covert channel bandwidth may be significantly different when measured in settings that are independent of the specific environments of operation, including laboratories or system development environments.

## Risk Assessment

| Finding                                                                | Severity | Impact                                          |
| ---------------------------------------------------------------------- | -------- | ----------------------------------------------- |
| SC-31(3) Measure Bandwidth in Operational Environments not implemented | High     | System and Communications Protection            |
| SC-31(3) partially implemented                                         | Medium   | Incomplete System and Communications Protection |

## CWE Categories

| CWE ID  | Title                                |
| ------- | ------------------------------------ |
| CWE-311 | Missing Encryption of Sensitive Data |

## References

- [NIST SP 800-53 Rev 5 - SC-31(3)](https://csrc.nist.gov/projects/cprt/catalog#/cprt/framework/version/SP_800_53_5_1_1/home?element=sc-31.3)
- [NIST SP 800-53A Rev 5 (Assessment Procedures)](https://csrc.nist.gov/pubs/sp/800/53/a/r5/final)
- [NIST SP 800-53 Rev 5 Full Catalog](https://csrc.nist.gov/pubs/sp/800/53/r5/upd1/final)

## Checklist

- [ ] Control documented in SSP
- [ ] Implementation evidence collected
- [ ] Operating effectiveness validated
- [ ] Continuous monitoring in place
- [ ] Related controls (none) reviewed