What is Shared Responsibility Model?

Understanding Shared Responsibility Model

The Shared Responsibility Model clarifies security obligations between cloud providers and their customers, recognizing that while providers secure underlying infrastructure, customers must protect what they put in the cloud. Responsibilities vary by service model: Infrastructure-as-a-Service typically leaves OS and application security to the customer, while the provider ensures physical data centers and networking. Platform-as-a-Service extends provider responsibilities to OS and runtime, leaving the customer responsible for data, configurations, and user access. Software-as-a-Service providers handle nearly all aspects except user management and data security settings. Effective usage requires that organizations thoroughly review provider documentation to identify where their accountability lies, enforce adequate security configurations, and integrate cloud controls into existing risk management frameworks. Pitfalls include misunderstanding boundaries (e.g., assuming the cloud provider handles app-level patches), ignoring security best practices because “it’s in the cloud,” and failing to handle data privacy obligations. A well-executed shared responsibility approach ensures both parties uphold their portion of security, reducing misconfigurations and creating a cohesive, defense-in-depth architecture.