---
title: "NIST 800-171 3.13.7 (SC.L2-3.13.7): Split Tunneling"
description: "NIST SP 800-171 3.13.7 Split Tunneling: 1 SPRS point, allowed on a CMMC POA&M. The text, what assessors check and the evidence."
url: https://policycortex.com/nist-800-171/system-and-communications-protection/3.13.7
sealed: 2026-11-11
amended: 2026-11-11
register: nist-800-171/system-and-communications-protection/3.13.7
records: 7
digest: sha3:b6a9b1382ae981739667d58f36f5d5d3b6108843fd5185e4d6bb42955ea69cf8
---

# NIST 800-171 3.13.7 (SC.L2-3.13.7): Split Tunneling

NIST 800-171 / System and Communications Protection / 3.13.7

"Prevent remote devices from simultaneously establishing non-remote connections with organizational systems and communicating via some other connection to resources in external networks (i.e., split tunneling)." ([NIST SP 800-171 Rev. 2, requirement 3.13.7](https://doi.org/10.6028/NIST.SP.800-171r2))

CMMC Level 2 practice SC.L2-3.13.7.

## What 3.13.7 means in practice

A remote device connected to your network must not be connected to another network, such as the internet, at the same time. Configure VPN clients to send all traffic through the tunnel, or otherwise stop the device from bridging the two.

## SPRS points and the CMMC POA&M

- **CMMC Level 2 practice**: SC.L2-3.13.7
- **SPRS points**: 1 point. When it is not met, the DoD Assessment Methodology subtracts 1 from the score of 110.
- **CMMC POA&M**: Allowed. It is worth 1 point, and 32 CFR 170.21(a)(2)(ii) admits requirements worth 1 point. Conditional status also needs a score of at least 88, and the item must be closed within 180 days.

Sources: [NIST SP 800-171 DoD Assessment Methodology, version 1.2.1 (June 24, 2020), Annex A](https://www.acq.osd.mil/asda/dpc/cp/cyber/docs/safeguarding/NIST-SP-800-171-Assessment-Methodology-Version-1.2.1-6.24.2020.pdf); [32 CFR 170.21, Plan of Action and Milestones requirements](https://www.ecfr.gov/current/title-32/section-170.21).

## What an assessor checks for 3.13.7

NIST SP 800-171A gives one determination statement for 3.13.7.

- Determine if remote devices are prevented from simultaneously establishing non-remote connections with the system and communicating via some other connection to resources in external networks (i.e., split tunneling).

[NIST SP 800-171A (June 2018), assessment objectives for 3.13.7](https://doi.org/10.6028/NIST.SP.800-171A)

## Evidence that shows 3.13.7 is met

- VPN client or concentrator settings that force all traffic through the tunnel.
- Device management settings that stop users from changing the VPN configuration.
- A test from a connected device showing internet traffic goes through the tunnel.

## How PolicyCortex gathers the evidence

PolicyCortex reads this evidence with the collectors below, read only, and grades 3.13.7 from it. Each line says what the product checks.

- **Azure: VPN gateways.** Reads Azure VPN gateway configuration and checks that split tunneling is prevented for remote access connections.

## Related pages

- **Calculator**: [SPRS score calculator: mark 3.13.7 and the other 109 requirements and see the score.](https://policycortex.com/sprs-score-calculator#family-SC)
- **Sample package**: [Sample package: an SSP, a POA&M and an evidence chain the product generated from demonstration data.](https://policycortex.com/sample-package)
- **Family**: [All 16 System and Communications Protection requirements (3.13).](https://policycortex.com/nist-800-171/system-and-communications-protection)
- **Previous**: [3.13.6: Deny by Default](https://policycortex.com/nist-800-171/system-and-communications-protection/3.13.6)
- **Next**: [3.13.8: Encryption in Transit](https://policycortex.com/nist-800-171/system-and-communications-protection/3.13.8)
- **All requirements**: [All 110 NIST SP 800-171 requirements, by family.](https://policycortex.com/nist-800-171)

Meet the requirement once. Keep the evidence current. [Request Access](https://app.policycortex.com/auth?mode=request-access) · [Book a call](https://policycortex.com/book)

## Register colophon

| Seq | Label | SHA3-256 | Prev |
|---|---|---|---|
| REC 0000 | REQUIREMENT | 72921d203ef1 | 99669b9a4a79 |
| REC 0001 | MEANING | 00aaa7402b1b | 72921d203ef1 |
| REC 0002 | POINTS AND POA&M | 30aa7c7942c2 | 00aaa7402b1b |
| REC 0003 | ASSESSMENT OBJECTIVES | f1c2cd25f73e | 30aa7c7942c2 |
| REC 0004 | EVIDENCE | 2c8de4c28214 | f1c2cd25f73e |
| REC 0005 | COLLECTORS | b04fdc69e2a1 | 2c8de4c28214 |
| REC 0006 | RELATED | b6a9b1382ae9 | b04fdc69e2a1 |

Head sha3:b6a9b1382ae981739667d58f36f5d5d3b6108843fd5185e4d6bb42955ea69cf8. Each digest is SHA3-256 over the previous digest, the register key, the record label, and the record copy; a second party can recompute it from this document.