Security in the Cloud
Cloud computing shifts some security responsibilities to the provider, but not all. The shared responsibility model defines who secures what — the provider secures the infrastructure, and you secure your data, configurations, and applications.
Shared Responsibility Model
- Cloud provider responsibility — physical security, hypervisor, network infrastructure
- Customer responsibility — data encryption, IAM policies, application security, OS patching
- Shared — network controls, logging, compliance
Network Segmentation
Virtual Private Clouds (VPCs) isolate your resources in a private network. Subnets, security groups, and network ACLs control traffic flow. Public subnets face the internet; private subnets are accessible only from within the VPC.
A common misconfiguration: placing databases in public subnets with open security groups. Always put data stores in private subnets with strict ingress rules.
Key Takeaway
Cloud security is a shared responsibility. You own your data, IAM, and application security — the provider owns the physical infrastructure.