The firewall creates a barrier that traffic going in the other direction must pass through. It functions as a filter at the IP packet level and offers an effective method for protecting, monitoring, and auditing the local network against external network security threats, IP address spoofing, and routing attacks.
A proxy server is also known as an application gateway because it controls traffic at the application level. Despite examining raw packets, it filters data based on header fields, message size, and content.
The firewall and proxy server work in integration. However, the proxy server is a component of the firewall that, when used in conjunction with the firewall, provides performance and greater efficiency.