Understanding Shared Responsibility Model in AWS, Azure & Google Cloud

The shift to cloud computing has revolutionized the way businesses operate. However, with this flexibility comes the critical need to understand security responsibilities. One of the most important concepts to grasp is the Shared Responsibility Model. Whether you use AWS, Microsoft Azure, or Google Cloud Platform (GCP), knowing who is responsible for what—between you and the cloud provider is essential for compliance, risk management, and security. In this 3000+ word guide, we break down the shared responsibility model in AWS, Azure, and GCP in detail.

What is the Shared Responsibility Model?

The shared responsibility model defines the division of security and compliance tasks between the cloud service provider (CSP) and the customer. In traditional on-premise environments, businesses manage the entire stack—from physical servers to application logic. In contrast, in the cloud, some responsibilities shift to the provider.

The division of responsibilities typically depends on the type of cloud service model you're using:

• IaaS (Infrastructure as a Service): You manage OS, data, apps; provider manages network, storage, compute.
• PaaS (Platform as a Service): You manage data and apps; provider manages runtime, OS, and infrastructure.
• SaaS (Software as a Service): You manage only data and user access; provider manages nearly everything else.

Why is Understanding This Model Important?

Misunderstanding the shared responsibility model is one of the top causes of cloud security incidents. Many companies assume that the cloud provider is responsible for all aspects of security—which is incorrect. Knowing your role helps you:

• Prevent misconfigurations
• Meet compliance and regulatory standards
• Reduce costs by focusing on relevant tools and protections
• Manage risks effectively

Shared Responsibility in AWS

Amazon Web Services (AWS) uses a very clear model: "Security OF the cloud" is AWS’s responsibility, while "Security IN the cloud" is yours.

AWS Responsibilities

• Physical infrastructure (data centers, hardware)
• Global network and regions
• Compute, storage, database, networking infrastructure
• Managed services security (e.g., RDS, DynamoDB)

Customer Responsibilities

• Data classification and protection
• Identity and access management (IAM)
• Application-level security
• Operating system patches and configurations (for EC2)
• Firewall rules and network ACLs

Shared Responsibility in Microsoft Azure

Microsoft Azure offers a similar model but presents it in the context of shared ownership across infrastructure, platform, and software services.

Azure Responsibilities

• Physical data center and network security
• Host infrastructure and virtualization
• Platform-level controls and services
• Compliance with global standards

Customer Responsibilities

• Information and data classification
• Endpoint security
• Account and identity management (Azure AD)
• Custom application code and configurations
• Network security (NSGs, firewalls)

Shared Responsibility in Google Cloud Platform (GCP)

Google Cloud also adheres to a shared responsibility structure, with detailed documentation on user and provider roles based on service type.

GCP Responsibilities

• Physical infrastructure, hardware, and facilities
• Network layer security and uptime
• Service availability and patching of managed services

Customer Responsibilities

• Application development and deployment
• Data encryption and access control policies
• IAM role definitions and monitoring
• Configuration of network policies

Comparative Table: AWS vs Azure vs GCP

Responsibility	AWS	Azure	Google Cloud
Data Center Security	AWS	Azure	GCP
Identity & Access Mgmt	Customer	Customer	Customer
OS Patching (IaaS)	Customer	Customer	Customer
Service Patching (SaaS)	AWS	Azure	GCP
Compliance	Both	Both	Both

Best Practices for Managing Your Responsibilities

• Understand Your Role: Review your cloud provider’s documentation regularly to stay updated on responsibilities.
• Enable Logging & Monitoring: Use tools like AWS CloudTrail, Azure Monitor, and Google Cloud Operations.
• Use Identity Best Practices: Enable MFA, rotate keys, and enforce least privilege access.
• Automate Compliance Checks: Tools like AWS Config, Azure Policy, and GCP Security Command Center help maintain posture.
• Patch Management: Use automated patching for IaaS and always update libraries and runtime for PaaS and containers.

Conclusion

The shared responsibility model is a foundational concept for cloud security. It ensures that both the cloud provider and the customer know their roles in securing cloud environments. By understanding how AWS, Azure, and Google Cloud divide responsibilities, businesses can make informed decisions, stay compliant, and protect their assets more effectively.

If you're not sure how to manage your responsibilities, Tial Wizards offers consulting, audits, and implementation services to help you align with shared responsibility frameworks. Visit Tial Wizards to get started.