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ATO Path and Assumptions

Use this document to lock the working strategy before writing detailed control narratives. The wrong authorization path or baseline will create rework across the SSP, POA&M, assessment plan, and continuous monitoring package.

Working Position

DecisionCurrent Template AnswerOwnerEvidence Needed
Authorization pathAgency Authorization[FILL IN: owner]Sponsoring agency and AO confirmation
Target baselineFedRAMP Moderate by default; High-ready technical posture where practical[FILL IN: owner]FIPS 199 worksheet
Cloud service modelSaaS with managed infrastructure and Kubernetes workloads[FILL IN: owner]Architecture diagram and service inventory
Deployment boundary[FILL IN: production boundary][FILL IN: owner]Boundary diagram
Data residencyUnited States only unless explicitly approved[FILL IN: owner]Hosting region list and data-flow review
Operator residencyUS-person operations for federal boundary where required[FILL IN: owner]Staffing and support model
3PAO[FILL IN: candidate 3PAO][FILL IN: owner]Engagement plan
Initial package date[FILL IN: target date][FILL IN: owner]Roadmap and POA&M burn-down

Readiness Standard

The template goal is ATO compatibility, not an authorization claim. A control is ready only when the behavior is implemented, the owner is named, the evidence exists, and the evidence can be reproduced without manual archaeology.

Stakeholders

RoleNameResponsibilityBackup
System Owner[FILL IN]Owns system mission, boundary, and risk posture.[FILL IN]
Authorizing Official[FILL IN]Accepts or rejects residual risk.[FILL IN]
ISSO[FILL IN]Coordinates security package and control evidence.[FILL IN]
ISSM[FILL IN]Owns security program oversight.[FILL IN]
Platform Engineering Lead[FILL IN]Owns Kubernetes, GitOps, CI/CD, and runtime controls.[FILL IN]
Application Engineering Lead[FILL IN]Owns application controls, tests, and release changes.[FILL IN]
Privacy Lead[FILL IN]Owns PII inventory, minimization, retention, and privacy risk.[FILL IN]
3PAO Lead[FILL IN]Owns assessment planning and reporting.[FILL IN]

Open Assumptions

AssumptionWhy It MattersValidation PathStatus
The first federal target can accept FedRAMP Moderate.Determines baseline scope and evidence burden.Complete FIPS 199 with agency sponsor.Open
Production can run in a US-only cloud boundary.Supports data residency and personnel requirements.Confirm region, support, and subprocessors.Open
Identity can support phishing-resistant MFA.Required for higher-assurance identity posture.Validate IdP and WebAuthn or PIV/CAC support.Open
CI/CD can generate SBOM, provenance, and signed artifacts.Supports supply-chain and change-control evidence.Add pipeline controls and preserve artifacts.Open
Monthly ConMon can be automated from GitHub, cluster scans, and dashboards.Reduces ongoing authorization cost.Define evidence exporters and storage locations.Open

Authorization Risks

RiskImpactMitigationPOA&M Needed
Boundary is unclear.Control inheritance and assessment scope become disputed.Create a boundary diagram and data-flow diagram before SSP drafting.Yes
Evidence is manual.Controls may be considered partially implemented.Prefer automated scan output, signed release artifacts, and immutable logs.Yes
Crypto is not FIPS validated.SC controls may fail at Moderate or High.Select validated modules or document inherited cloud-provider validation.Yes
Access review process is not repeatable.AC and IA controls remain partial.Schedule quarterly access-review issues with exports attached.Yes
Continuous monitoring is treated as a one-time task.Authorization may be delayed or lost after approval.Build monthly ConMon rhythm before assessment.Yes

Immediate Decisions

  • Confirm agency sponsor and target authorization path.
  • Complete FIPS 199 categorization.
  • Confirm target baseline: Low, Moderate, or High.
  • Confirm production boundary and hosting regions.
  • Decide which controls are inherited from cloud, GitHub, identity, and managed services.
  • Identify 3PAO timeline and required pre-assessment evidence.
  • Create initial POA&M items for every known gap.