1.5.1. Shared Responsibility: Microsoft's Role

💡 First Principle: Microsoft's fundamental responsibility is the "security of the cloud," which means they are accountable for protecting the global physical and logical infrastructure that delivers all Azure services, allowing customers to build on a secure foundation.

Scenario: You are designing a CI/CD pipeline in Azure DevOps. You are concerned about the physical security of the data centers where Azure DevOps services run and the patching of the underlying operating systems for Azure DevOps agents that Microsoft manages.

In the Azure Shared Responsibility Model, Microsoft's responsibility is to protect the infrastructure that runs all of the services offered in Azure. This "security of the cloud" includes protecting the global infrastructure (Regions, Availability Zones) and the hardware, software, networking, and facilities that run Azure services.

Key Microsoft Responsibilities ("Security of the Cloud"):

• Physical Security: Data centers, servers, networking hardware.
• Network Controls: Global Azure network backbone and infrastructure.
• Host OS: Operating systems of the physical hosts providing Azure services.
• Virtualization Layer: The hypervisor that isolates customer Virtual Machines.
• Managed Services Infrastructure: Underlying infrastructure for Azure DevOps (e.g., Azure Pipelines agents, Azure Boards), Azure App Service, Azure Functions, Azure Storage, etc. This includes patching and security configuration of these underlying hosts and platform components.

⚠️ Common Pitfall: Assuming Microsoft's responsibility extends to the customer's data or application logic running on the platform. Microsoft secures the container, but the customer secures the contents.

Key Trade-Offs:

• Control vs. Security Burden: By using Azure's managed services, you cede control over the underlying infrastructure in exchange for Microsoft taking on the significant burden of securing it.

Reflection Question: How does Microsoft's "security of the cloud" responsibility, by managing the physical security and underlying infrastructure for managed Azure services (like Azure DevOps), enable a DevOps engineer to focus on pipeline security, application code, and data, rather than the foundational environment?