AWS Certified Advanced Networking - Specialty Exam Guide

Layer 3

The next layer of security would be on layer 3, which should secure all IP communication. Layer 3 spans all our subnets and all of the internet. Essentially, when we talk about layer 3 protection, we are talking about stateless firewalls. These work in a way that allows everyone to connect from the get-go and then once bad actors on the network are detected, the IP addresses or ranges of these actors are blocked. Layer 3 firewalling can also help with specific network isolation requirements that need to be implemented due to compliance reasons. For example, we would only want a certain IP address range to communicate with another specific IP address range.

This can be simply implemented with layer 3 stateless rules. Stateless firewalls ...