Stateful and Stateless Firewalls

Firewall

Firewalls help protect resources from unwanted connection requests and access. We can restrict access to our AWS resources over a network using a firewall. AWS offers two types of firewalls to protect the resources within a VPC from unwanted connection requests and access. These are called stateful and stateless firewalls. Before going into the details of these firewalls, let’s understand how data packet transfer occurs in a typical web connection between a client and server.

Request and response

Let’s assume we want to go to Google’s homepage. We’ll go to the browser and make a request to https://www.google.com, and in return, we will get a response from Google’s server showing the home page in the browser. Now, let’s examine the same request and response with the help of a Linux terminal.