Knox Systems now supports customers seeking IL5 accreditation, the highest cloud security certification that enables software providers to work with the U.S. military.
Federal cloud authorization, from civilian to defense
Selling software to the U.S. government means navigating two major frameworks: FedRAMP for civilian agencies, and the DoD Cloud Computing SRG for defense. Here's how they relate, when you need each, and how to operate across both.
How the Frameworks Stack UpFedRAMPNIST SP 800-53IL4FedRAMP + DoD overlaysIL5FedRAMP High + NSS
Trusted across 16 inheritable ATOs and top federal Sponsors
Before FedRAMP or DISA Impact Levels, there is FIPS 199 — the standard that classifies every federal system by the impact of a security breach.
FIPS 199 rates systems across confidentiality, integrity, and availability, then categorizes each as Low, Moderate, or High. Those categories determine the required security controls. FedRAMP applies FIPS 199 to cloud systems. The DoD Cloud Computing SRG builds on FedRAMP, and Impact Levels extend those requirements for defense use.
Confidentiality · Integrity · AvailabilityLow · Moderate · High
Civilian vs. defense
Two frameworks, one lineage
FedRAMP standardizes cloud security for civilian agencies. The DoD Cloud Computing SRG takes that same baseline and adds defense-specific requirements on top.
FedRAMP
The standard for civilian federal agencies
FedRAMP produces a standardized, reusable authorization package assessed against NIST SP 800-53. Each agency reviews that package and issues its own ATO based on mission and risk tolerance.
NIST SP 800-53Low · Moderate · High
DoD CC SRG
The framework for defense cloud security
Governed by DISA, the DoD Cloud Computing SRG applies Impact Levels (IL2, IL4, IL5, IL6) on top of FedRAMP baselines to address DoD-specific data sensitivity and mission requirements.
DISAIL2 · IL4 · IL5 · IL6
CUI and Impact Levels
How the DoD measures data sensitivity
Controlled Unclassified Information (CUI) is sensitive government data that is not classified, but still requires protection, such as export-controlled data, critical infrastructure information, health information, law enforcement data, and mission-related operational data. Impact Levels define how sensitive DoD data is and what protection it requires.
IL2Impact Level 2
Low-sensitivity, public or non-critical data
Roughly aligned with FedRAMP Moderate
Not typically relevant for most SaaS companies
IL4Impact Level 4
Primary level for CUI workloads
Based on FedRAMP Moderate or High, plus DoD FedRAMP+ controls and CNSSI 1253 overlays, depending on data categorization
Supports confidentiality / integrity levels up to MMx or HHx
Requires a DISA Provisional Authorization (PA)
IL5Impact Level 5
Unclassified National Security Systems and National Security Information (NSS / NSI)
Based on FedRAMP High, plus DoD FedRAMP+ controls, CNSSI 1253 overlays, and NSS controls
Elevated-protection CUI may also be hosted here when required
Requires stronger isolation and access controls than IL4
Layered, not separate
Impact Levels extend FedRAMP. They don't replace it.
The frameworks stack. FedRAMP is the baseline. Impact Levels are a DoD construct applied on top of that baseline to address defense data sensitivity and mission requirements. Each level builds on everything below it and adds more.
FedRAMPIL4IL5Civilian agenciesThe federal baseline.NIST 800-53 · Agency ATODoD CUI workloadsLayered on FedRAMP.FedRAMP+ · DISA PANSS / NSI workloadsNational security systems.FedRAMP High · DISA PA
Quick comparison
FedRAMP vs. IL4 vs. IL5
The same security lineage, escalating by data sensitivity and mission requirements.
FedRAMP
IL4
IL5
Governing body
GSA / FedRAMP PMO
DISA
DISA
Primary use
Civilian agencies
DoD CUI workloads
DoD NSS / NSI workloads
Security baseline
NIST SP 800-53
FedRAMP Moderate or High + DoD overlays
FedRAMP High + DoD overlays
Data type
Low, Moderate, High
CUI
NSS / NSI (with some elevated CUI)
Authorization
Agency ATO
DISA Provisional Authorization
DISA Provisional Authorization
Typical entry point
Moderate
IL4
IL5
See where your product lands across both frameworks.
Many companies move through all three over time, FedRAMP for baseline authorization and civilian adoption, IL4 for initial DoD entry, and IL5 for deeper defense and national security work.
You need FedRAMP if
You're selling to civilian agencies
You want broad federal market access
You need IL4 if
You're selling to the Department of Defense
Your product handles CUI
You're entering DoD environments
You need IL5 if
You're supporting national security workloads
Your system is classified as NSS / NSI
Higher isolation and assurance are required
Not sure which level applies to you? Talk it through with our team.