What is a Proxy Firewall? Uses & Benefits

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Almost one-third of companies have over 100 firewalls set up in their network., and it’s no secret why. They protect against cyber attacks and malicious traffic. 

Proxy firewalls work similarly, except that they add another layer of security by intercepting all data requests. 

You’re at the right place if you’re curious to learn how they apply in the real world. Here’s what you should know about the uses and benefits of proxy firewalls.

Understanding Proxy Firewall

A proxy is a server that stands between you and the internet. A firewall is a security system that monitors data traffic for malicious content. Combine the two, and you’ve got a proxy firewall. 

This network security device has two main functions: intercepting outgoing requests and analyzing incoming data. That means masking your IP while protecting your network from cyber-attacks. 

Most importantly, they never directly let your real IP contact an external server. Proxy firewalls operate on strict rules on which apps can transmit data and which aren’t.

Since this system filters the data exchange at the application layer, it’s also called an application-level gateway.

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How Do Proxy Firewalls, AKA Application-Level Gateways Work? 

Application-level gateways (ALGs) mediate your conversation with an external server. Here’s what they look like in action. 

Step 1: Interception

The proxy firewall positions itself between you and the internet. It intercepts your outgoing requests for web resources to conceal your IP. Then, it forwards them as if the proxy is the request’s origin.

Step 2: Protocol Filtering

The ALG analyzes the application layer protocols, such as HTTP, FTP, or DNS, to ensure everything’s up to code. That means everything should be sticking to the predefined set of rules. 

Step 3: Content Inspection

ALGs examine the actual content of data packets. They search for signs of malicious code, viruses, or unauthorized access attempts. 

Step 4: User Authentication

The ALG must verify your identity before giving you access to the requested resource. You’ll need to enter your username, password, or other credentials.

Step 5: Connection

Finally, the proxy firewall connects to the external server on your behalf. This way, your network details are hidden, and there’s no direct exposure to cyber threats.

Step 6: Cache-Control

The ALG keeps a detailed log of all your online activities during its use. It’ll also cache the content you request access to the most often. Now, the next time you ask for the same content, you’ll receive it much faster since it’s stored locally. 

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Exploring Some Examples of How a Proxy Firewall Works 

Proxy firewalls control and filter your interaction with the internet. Since they operate simply, consider them an entry-level firewall.

For example, an employee wants to visit a social media website. Instead of connecting directly to the site, their request goes through the proxy firewall. It’ll check the request, the site’s reputation, and the presence of malware.

Meanwhile, the network administrator (the company) has set certain rules for access. Since access to social media sites is restricted, the proxy firewall won’t fulfill the employee’s request.

Let’s look at another example. 

A business has connected its branches using a Wide Area Network (WAN). The proxy firewall at each location will monitor their internet usage and protect sensitive company data. It’ll also keep a log of who’s accessing what. 

In this last scenario, a company’s app has been targeted by a DDoS attack. The malicious traffic floods the company’s servers without a proxy firewall in place. Eventually, the servers get overloaded and stop working for legitimate users.

Advantages & Disadvantages of Proxy Firewalls

Proxy firewalls have an advantage over other firewall types but have their fair share of downsides.

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Proxy firewalls are comprehensive and protocol-aware. They support many protocols, including HTTP, HTTPS, FTP, DNS, and more. Their position at the application layer opens doors for smarter security decisions instead of focusing on packet header information.

Extensive Logging Capabilities

Proxy firewalls make robust, protocol-aware logging a reality. Logging makes it much easier to identify and mitigate cyber-attacks and protect your network. It also keeps a backup of logs on all networks the proxy is protecting.


Unlike most firewall types, proxy firewalls offer much control and granularity. You can configure them however you like, whether applying different security levels for different users or keeping access logs on user activities. 


Since it operates on a proxy server, this firewall type also has caching capabilities. It stores certain resources locally, the ones you request access to the most. Caching allows for faster load speeds since they can fetch the resources from the local storage every time.

Threat Assessment

Research by IBM tells us it typically takes 280 days to contain an average cyber-attack. But that’s not true for proxy firewalls! They allow programmers to predict attacks by assessing a protocol’s threat levels and fixing all errors.

Improved Performance

Proxy firewalls can improve your web performance if used correctly thanks to good caching and load balancing. You’ll enjoy lower latency and risk-free browsing.


Difficult to Use & Setup

Over 40% of proxy firewalls are hosted entirely on-premise, which makes them pretty hard to set up. This is especially true when dealing with older proxies since they’re tricky to configure according to your network.

May Slow the Internet Connection

Proxy firewalls have two ongoing functions – setting up two connections for each request and validating them at the application layer. The extra overhead comes at a cost: slower performance. But you may be able to balance it by investing in high-end servers.


Proxy firewalls may not be compatible with all network protocols. You’ll need to develop a new proxy agent before a new protocol passes through the firewall. If your proxy doesn’t support a necessary protocol, you may need to stick with a generic proxy instead.

Encryption & Privacy Concerns

Since proxy firewalls cache certain data, your personal details may get decrypted out of the blue. Look for a trustworthy proxy provider and ensure end-to-end encryption to protect sensitive data.

Proxy Firewall vs Traditional Firewall – What Are The Differences?

Here are a few main differences between proxy firewalls and traditional firewalls. 

  • Regular firewalls protect network borders by managing traffic. Meanwhile, proxy firewalls create a safety zone between internal and external networks. They keep both traffic flows separate for an extra layer of protection.
  • Proxy firewalls create mirrored connections, but traditional ones don’t. As a result, they can’t hide where the internet traffic is coming from. That makes it easier for third parties to expose internal data.
  • Regular firewalls handle things on a basic level at layers 3 and 4. Meanwhile, proxy firewalls focus on the applications you use at layer 7. They pay closer attention to your internet activities for better security.
  • Proxy gateways serve as filters for different internet protocols. You can use them to control internet traffic, like blocking certain types of data from file-sharing or emails in a company. They decide what information can pass through and what gets blocked.
  • Unlike traditional firewalls, proxy firewalls have cache storage. They can record online activities and help with audits and analysis. Caches also allow you to control network traffic for better data flow.

Final Words

It’s clear why 95% of buyers are satisfied with their proxy firewall’s capabilities. They hide your identity, protect your server from malware, and do it on one main hub. Use our guide and find the right proxy wall to secure your network. 

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Expert in mobile proxies, internet privacy, SEO marketing and sales.
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