# NIST SP 800-53 Rev. 5 SA-8(18) — Trusted Communications Channels - Source: https://support.icompaas.com/compliance/nist-sp-800-53-rev-5/sa-8-18-trusted-communications-channels - 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) › SA — System and Services Acquisition - Last updated: 2026-06-05 - Publisher: iCompaas, Inc. (https://www.icompaas.com) **NIST SP 800-53 Rev. 5**·Control `SA-8(18)`·high·Component: **System and Services Acquisition** ## What this control requires > Ensure communication channels are trustworthy relative to their security roles by restricting access and applying end-to-end protections to guard against interception, modification, and trust mismatches. This control supports the Secure Channel Enforcement Layer capability within the System and Services Acquisition family. > > — NIST SP 800-53 Rev. 5, Control SA-8(18) ### In plain English Ensure communication channels are trustworthy relative to their security roles by restricting access and applying end-to-end protections to guard against interception, modification, and trust mismatches. In practice, this means you can prove you access 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 Services Acquisition**, the assessor will trace your implementation back to the catalogue reference (Control SA-8(18)) and look for objective evidence on the latest two assessment cycles. ## How to implement #### Physical Security **Inheritance.** For cloud-only operations, inherit physical controls from the provider's SOC 2 / ISO 27001 report and document the inheritance in the SoA. ### Operational checklist - **Access.** Document the trigger, the owner and the cadence. - **Security.** Document the trigger, the owner and the cadence. - **Physical.** Document the trigger, the owner and the cadence. - **Review.** Document the trigger, the owner and the cadence. - **System.** Document the trigger, the owner and the cadence. - **Scope:** management, enforcement, system, identity, review, services, capability, roles. ## Evidence to collect - **Identity Scan.** IAM / IdP exports — Entra ID, Okta, IAM Identity Center, Workspace directory — showing accounts, roles, MFA state and last sign-in. Identity analytics (Okta, SailPoint, Access Analyzer) demonstrates least-privilege. Focus: Trusted Communications Channels. ## 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. - [**ISO/IEC 27001:2022 A.7.2** — Physical entry](https://support.icompaas.com/compliance/iso-27001-2022/a-7-2-physical-entry) - [**NIST SP 800-171 Rev. 3 3.15.2** — System Security Plan](https://support.icompaas.com/compliance/nist-sp-800-171-rev-3/3-15-2-system-security-plan) - [**CIS Controls v8 9.2** — Use DNS Filtering Services](https://support.icompaas.com/compliance/cis-controls-v8/9-2-use-dns-filtering-services) - [**SOC 2 (2017 TSC) CC6.2** — Access Provisioning](https://support.icompaas.com/compliance/soc-2-trust-services-criteria/cc6-2-access-provisioning) ## Related controls in NIST SP 800-53 Rev. 5 - [**Control SA-8(9)** — Trusted Components](https://support.icompaas.com/compliance/nist-sp-800-53-rev-5/sa-8-9-trusted-components) - [**Control SA-3** — System Development Life Cycle](https://support.icompaas.com/compliance/nist-sp-800-53-rev-5/sa-3-system-development-life-cycle) - [**Control SA-8(23)** — Secure Defaults](https://support.icompaas.com/compliance/nist-sp-800-53-rev-5/sa-8-23-secure-defaults) - [**Control SA-8(14)** — Least Privilege](https://support.icompaas.com/compliance/nist-sp-800-53-rev-5/sa-8-14-least-privilege) - [**Control SA-8(22)** — Accountability And Traceability](https://support.icompaas.com/compliance/nist-sp-800-53-rev-5/sa-8-22-accountability-and-traceability) - [**Control SA-12(14)** — Identity And Traceability](https://support.icompaas.com/compliance/nist-sp-800-53-rev-5/sa-12-14-identity-and-traceability) ## 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 SA-8(18)` Topics: identity accessidentity managementaccess reviewprivileged accessphysical security ## 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.