Tech_Interview_Prep

Cloud-Native Network Security

Security groups, network ACLs, and private networking that control traffic flow within a cloud environment.

What it is

Cloud-native network security controls traffic flow using the cloud provider's own primitives — security groups, network ACLs, private networking — rather than traditional physical network appliances.

Key points

  • Security groups: stateful, instance-level firewalls — allow rules are typically sufficient since return traffic is automatically permitted, which is different from traditional stateless firewall rule design.
  • Private networking (VPCs, private subnets, private endpoints): keeps resources like databases off the public internet entirely, so they're unreachable regardless of any credential compromise elsewhere.
  • Defense in depth at the network layer: security groups plus network ACLs plus private subnets layer independent controls — a misconfiguration in one shouldn't fully expose a resource if the others are configured correctly.
  • Most real-world cloud breaches trace back to a network resource left unintentionally public — network security review is disproportionately high-leverage relative to its complexity.