Proxy vs. Firewall – Comprehensive Comparison in 2023

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By Jack

A comparison between Proxy vs. Firewall would be handy for any computer user with internet access.

That is because both Proxy and firewalls are security measures that can protect a computer from various network threats. So, continue reading this article to get a better idea about them.

Introduction to the Functionality of Firewall and Proxy

In general, both firewall and proxy technology perform in conjunction with protecting the computer. A firewall is placed at a lower level, and it can filter all varieties of data packets (IP packets).

On the other hand, proxy servers manage the network traffic that is related to applications installed in a system. A proxy server can either reject or allow the requests that come from outside clients to assure maximum privacy.

Considering the functionality, a proxy server can be placed as a part of your system’s firewall. The purpose of a firewall is to prevent unauthorized connections from accessing your system. The proxy server plays the role of a mediator in connecting your system with a public network (the internet).

Proxy vs. Firewall – a Comparison Table

The aspect comparedFirewallProxy
Basic functionalityA firewall can monitor and filter all the incoming and outgoing traffic on a given local network.A proxy server connects an external client with a server to communicate with each other.
What does it filter?Firewalls filter data by monitoring IP packets that are traversed. Then, it blocks packets that may have harmful content to the system.The proxy server filters the client-side requests that are made to connect to the network.
What is the amount of generated overhead?Relatively moreRelatively less
What does it involve?The firewall involves network and transport layer data.Proxy servers work on application layer data.

Describing the Functionality of a Firewall

To make this Proxy vs. Firewall comparison a better one, we describe each aspect separately. First, let’s see how we can describe the functionality of a firewall.

Basically, the firewall works as a barrier to network traffic. However, it doesn’t block all the traffic; instead, it identifies and blocks potentially harmful connections only. In a way, a firewall works as a filter at the level of IP packets.

As a result, it can work effectively to protect, monitor, and audit local networks. This system can protect your local area network from potential intruders, IP spoofing, etc. This is an integrated solution when it comes to network security. As a result, it can offer security for both hardware and software aspects of the system.

A firewall is a system that comprises of packet filtering system as well as a proxy server. A proxy server in the firewall can also be considered as an application gateway.

A packet filtering system is used to detect all incoming and outgoing packets. If the system detects a suspicious packet, that will be blocked.

To do that, the firewall has a special set of rules. The traversing packets on the network will be compared according to that set of rules by the firewall. This set of rules applies to the network and the transport layer header.

For instance, the source and destination address, protocol, port number, etc., are observed under this rule. If there is a mismatch, the respective packets will be blocked immediately.


However, on the other hand, the proxy server can filter the application-level data, considering the message. We will explain it in detail in the below section, which is dedicated to the Proxy server.

The firewall has a couple of major strategies to deploy a successful operation and protect your data. With these strategies, a firewall can manage access and even enforce the required security policy. It utilizes service control, direction control, behavioral control, and user control strategies.

● Service Control

This firewall strategy specifies determining which internet services should be accessed. In this case, both inbound and outbound services are controlled.

● Direction Control

This strategy is to determine the route through which the respective data on the network should be traversed.

● Behavior Control

This strategy decides how the services should be utilized on the network.

● User Control

User control is the strategy that manages the access of a user to a given service within the network.

Describing the Functionality of a Proxy Server

In the world of network security, both proxy servers and application gateway have the same aspects. In other words, a proxy server is another name for an application gateway. It is called an application gateway, particularly because it controls the traffic based on applications.

A proxy server or an application gateway doesn’t observe the raw packets coming in or going out. Instead, it filters traversing data based on the header fields, content, and even the message size. Apart from that, there can be other parameters that can be used to filter data on a certain network.

As we have mentioned earlier, a proxy server can be identified as an element of a firewall. In other words, the firewall and proxy server should work together to deliver better security.

A firewall alone is not powerful enough to protect a network from all potential threats. That is particularly because it cannot necessarily tell apart port numbers.

In general, proxy servers play the role of a proxy and determines how the application-specific traffic flows. In that case, it determines URLs.

proxy server

Well, if you are curious about how proxies work, you should read this section as well. The proxy server stays between the original server and the client. Then, it utilizes a special server process, so it receives requests from the client.

The proxy server will then open the request and check its content to verify its legitimacy. If the content appears to be legitimate, the request will be accepted. Then, the proxy server will send the respective request to the original server, taking the client’s place.

On the other hand, if the request is not legitimate, it will be dropped immediately. Then, it will send an error message to the external user.

There is another advantage associated with proxy servers when compared to firewalls. When the proxy server receives a request, it deploys caching. Upon receiving a request, the server first checks if the respective page is already stored in cache memory. If it is already stored, the page will be reopened in no time.

However, if the page is not in the cache, the respective request will be sent to the server. As you can realize, this is a very efficient way to reduce potential traffic. This approach can practically minimize the load on the real server and speed up the process.

Proxy vs. Firewall – the Key Differences

In this section of our Proxy vs. Firewall comparison, we will emphasize their key differences. This will give you a better idea of these two aspects.

  1. In general, a firewall is mainly used to block potentially harmful traffic that can damage your system. It plays the role of a barrier for both incoming and outgoing traffic related to public networks. However, when it comes to a proxy server, it works as a component of a firewall. With the assistance of a proxy server, it establishes a connection between the client and the server. If the client is harmless and legitimate, it will play the role of client and server simultaneously.
  2. Firewalls are designed to monitor IP packets on your data network and filter them accordingly. On the other hand, a proxy server is designed to filter the requests that come from applications installed. That is why proxies are often called application gateways as well.
  3. In general, the overheads related to a firewall are more if you compare it with a proxy. That is especially because proxy servers use caching to minimize the usage of resources as much as possible.
  4. Firewalls are designed to use the network and transport layer data to monitor data traversing. However, when it comes to a proxy, it processes application layer data as well.

The Bottom Line

So, that’s our Proxy vs. Firewall comparison. A firewall and a proxy server should work together to deliver the expected protection to the network.

Nevertheless, a proxy server can be considered a part of a firewall, and it can boost the efficiency of a firewall.