AWS Network Firewall is a managed network security service that provides inbound and outbound traffic filtering for Amazon Virtual Private Clouds (VPCs). It is based on the open-source firewall software, Vyatta, and is designed to be highly scalable and resilient. It is a fully managed service that is available on a pay-as-you-go basis, so you only pay for what you use.
AWS Network Firewall is designed to help protect your VPC and the resources within it from unauthorized access over the internet. It does this by allowing you to create and manage firewall rules that control inbound and outbound traffic to your VPC. You can specify which IP addresses, protocols, and port numbers are allowed or denied access to your VPC, and you can use security groups to further fine-tune your firewall rules.
AWS Network Firewall includes several features that make it easy to set up and maintain firewall rules. It integrates with security groups, so you can use your existing security groups as the source or destination for your firewall rules. It also includes automatic rule updates, which means that the firewall rules are automatically updated to reflect changes to your VPC, such as when you add or remove resources.
In addition to controlling access to your VPC, AWS Network Firewall can also help protect against data loss by inspecting and monitoring traffic for signs of data exfiltration. It can alert you to suspicious activity and block traffic that appears to be attempting to extract data from your VPC.
AWS Network Firewall is a stateful, protocol-aware firewall service, which means it can track the state of each connection and apply the appropriate firewall rules. For example, if you allow inbound traffic from a specific IP address on a certain port, AWS Network Firewall will automatically allow the corresponding outbound traffic from your VPC to that IP address on that port