Network ACLs vs. Security Groups in AWS: Key Differences

Network ACLs and Security Groups are essential security tools in AWS, providing access control for your infrastructure. While both serve similar purposes, they have distinct characteristics. In this article, we will explore the key differences between Network ACLs and Security Groups to help you understand their unique roles.

Network ACLs: Subnet-Level Control

- Operate at the subnet level.
- Sequential rule evaluation.
- Granular control over inbound and outbound traffic.
- Stateless nature.
- Useful for fine-tuning access policies.

Security Groups: Instance-Level Control

- Operate at the instance level.
- No particular rule evaluation order.
- Control traffic to and from individual instances.
- Stateful nature.
- Support dynamic membership.

Conclusion

Network ACLs control traffic at the subnet level with sequential rule evaluation, while Security Groups operate at the instance level without a specific rule evaluation order. Network ACLs provide granular control, while Security Groups offer simplicity and dynamic membership. Understanding these differences allows you to leverage each tool effectively and design a secure AWS infrastructure.