Clarifying Cloud Foundations PaaS vs. IaaS for Federal Modernization

This ATARC cATO Working Group paper explains how Federal agencies should choose between Infrastructure-as-a-Service (IaaS) and Platform-as-a-Service (PaaS) to support secure modernization and faster mission delivery. The report outlines how misunderstanding cloud service models increases costs, delays Authorization to Operate (ATO) timelines and duplicates compliance efforts. IaaS offers maximum control but requires agencies to manage infrastructure, security and maintenance. PaaS embeds security, automation and compliance into the platform, reducing operational burden and enabling continuous delivery. Case studies demonstrate dramatic reductions in deployment timelines and compliance workload when automation and inherited controls are used. The paper recommends shared platforms, continuous authorization and outcome-focused acquisition to accelerate Federal cloud modernization.