# SC-07 (04) External Telecommunications Services — NIST 800-53 Rev5 control

> FedRAMP Consolidated Rules for 2026 v2026.07.14.01 · updated 2026-07-14
> Canonical page: /control/sc-7.4

Canonical id: `sc-7.4` · family `SC`

> (a) Implement a managed interface for each external telecommunication service; (b) Establish a traffic flow policy for each managed interface; (c) Protect the confidentiality and integrity of the information being transmitted across each interface; (d) Document each exception to the traffic flow policy with a supporting mission or business need and duration of that need; (e) Review exceptions to the traffic flow policy [frequency] and remove exceptions that are no longer supported by an explicit mission or business need; (f) Prevent unauthorized exchange of control plane traffic with external networks; (g) Publish information to enable remote networks to detect unauthorized control plane traffic from internal networks; and (h) Filter unauthorized control plane traffic from external networks.

_Control title and statement: NIST SP 800-53 Rev5 catalog (the pinned commit is in `/api` under `control_text`). The FedRAMP rules reference these controls by id only; everything below is what FedRAMP says about this id._

## Rev5 baseline membership

- certification class C (in the annual independent assessment)
- certification class D (in the annual independent assessment)

## Key Security Indicators that reach it

- `KSI-CNA-MAT` — Minimizing Attack Surface (Cloud Native Architecture)
  Machine-based information resources are persistently reviewed to ensure they have a minimal attack surface and that lateral movement is minimized if compromised.

## FedRAMP guidance

_No FedRAMP-specific guidance attaches to this control._

## Annual independent assessment

In the annual assessment subset for class C, D.