CGI Proxy: How It Works and What Is It Used For?

Whenever you deal with online data routing, you will likely encounter a proxy server. Most users are familiar with client-side proxies that provide an extra layer of anonymity by obfuscating the original IP address. For example, residential proxies are client-side because genuine internet users connect to them to bypass geographical restrictions or scrape the web.

A CGI proxy is a server-side component that manages client requests that include CGI scripts. These proxies are typically located on the same server and allow a more dynamic website structure. As you can see, they are significantly different from other proxies and demand a separate explanation in the vast proxy network constellation.

What Is a CGI Proxy?

CGI stands for Common Gateway Interface (not to be confused with Computer-Generated Imagery). This technology lets a web server communicate with external programs, called CGI scripts, to enhance website structure. To be more precise, it enables the display of dynamic content, which includes user interaction and personalization.

Readers familiar with IT will see similarities with JavaScript coding language, which developers also use to create dynamic and interactive websites. However, one of the key differences is that JavaScript is a client-side scripting language that executes on a client's device, typically in a web browser environment.

On the other hand, CGI optimizes website generation tasks on the server side. It can return a more personalized HTML structure according to client's requests, fetch information from external databases, and launch CGI scripts for numerous additional features. The latter include chatbots, search engines, shopping carts, and many more benefits crucial for modern e-commerce.

You may already see a potential issue: what if there are too many client CGI requests to a single web server? It will decrease the response time, forcing some users to go elsewhere and damage the website's ranking on search engines. Instead, networking professionals deploy CGI proxies to redistribute requests and save server resources. In this case, a CGI proxy is similar to (and can be considered a type of) reverse proxy, which is an essential load-balancing tool for content delivery networks (CDNs).

How CGI Proxies Differ from Other Proxies

Proxies are highly versatile and customizable networking technology, so there are many proxy types. In comparison, a virtual private network (VPN) can be considered a type of proxy because it also reroutes clients' data flow through a third-party server. However, a VPN is primarily focused on creating a secure and encrypted tunnel between the user's device and the internet, providing access to geographically restricted data and adding a layer of online anonymity. This is not the case with CGI proxies.

So, the first difference is that CGI proxy is a server-side component, and most internet users will not be aware of its existence. Whenever a web server (that uses a CGI proxy) sees a client request that includes CGI scripts, it reroutes it to a CGI proxy for processing. In this case, a web server acts as an intermediary between the client and CGI scripts that return a satisfactory response.

Let's take another example. SOCKS proxies are particularly popular among casual internet users to maintain unrestricted internet access by switching IPs. These proxies utilize the TCP connection, which is often used in peer-to-peer (p2p) traffic. In contrast, a CGI proxy does not obfuscate clients' IP addresses, cannot add an extra anonymity level to P2P traffic, and is not optimized for online privacy protection.

However, a CGI proxy can be considered a type of HTTP proxy. Both proxy types intercept and process HTTP requests and also transmit the response directly to the client. An HTTP request must include CGI script elements to be rerouted to the CGI proxy, which then processes it and returns an accurate response.

Use Cases for CGI Proxies

Just like there are numerous proxy server types, there are countless proxy use cases. Residential proxies excel at avoiding censorship and web scraping, while reverse proxies protect web servers from overloading and downtime. Meanwhile, a CGI proxy is primarily deployed in web development. Here are the five most common CGI proxy use cases.

Real-Time Data

One of the most visible CGI proxy use cases is the display of real-time data on a website without the need to refresh it. The everchanging currency exchange information on financial websites or temperature swings in weather forecast pages are often enabled by CGI.

At this point, it is worth noting that CGI technology is relatively old, at the hands of developers since the early 1990s. Although numerous alternatives, like Node.js, Django, or Ruby on Rails, exist, CGI proxies are still widely deployed among web servers to optimize CGI handling. Not only are they widely implemented on numerous web servers, but combined with CGI proxies, this data exchange method is highly efficient.

Getting back to real-time data display, CGI proxy can fetch financial, weather forecasts, or any other statistical data from external databases. One way of doing so is launching a CGI script to send an HTTP request to an API, which grabs the required data, sends it back to the CGI, and, finally, to the client.

Social Media Feed

Integrating social media feeds into a website is a great way to make it more attractive to visitors. Business websites can display positive user reviews, news sites include prominent personality posts, and personal blogs expand their audience reach. Such websites use CGI to grab information from social networks, which can also be displayed in real time, as per the previous example.

Once again, a CGI makes an API call to social networks. This benefits both parties because social networks get visibility on third-party websites, which are now rich with informative content. Depending on the scale of the website, a CGI proxy can be used to redistribute traffic from different social networks to reduce web server load.

IoT Device Data

IoT devices are now common in many households, from smart doorbells to Google's Nest devices to Amazon's Alexa and more. CGI scripts are used to fetch IoT data for a centralized display on a smartphone or computer and also enable remote control.

For example, Nest devices mark room temperature, which is processed by CGI and sent to the client. The owner can remotely adjust temperature settings, control the lighting, and live-stream videos.

Load Balancing

Efficient data exchange is attributed to CGI scripts, but there are tasks that are reserved for a CGI proxy server. Load balancing is one of the essential CGI proxy benefits because it makes websites load faster, saves server resources, and prevents downtime when experiencing sudden traffic increases.

A CGI proxy inspects the HTTP requests and redistributes them to correct CGI scripts. Although CGI proxies are often placed within the same web servers, they can also have a separate server or even a CGI proxy network for massive projects.

In this case, CGI proxies act as reverse proxies. Considering the ever-growing internet user count and video and audio quality increase, CGI proxies (or their alternatives) are in high demand to protect web servers from overloading.

Cybersecurity Benefits

Digital technologies that can intercept, analyze, and control web traffic have significant cybersecurity benefits. A CGI proxy can protect against SQL injections that aim to infect external databases, steal confidential data, or destroy them. It does so by filtering the requests and removing malicious elements that tamper with SQL databases.

However, this is relatively hard because experienced cybercriminals use the same CGI scripts to launch attacks, and telling malicious code from legitimate is challenging. The same logic applies to cross-site scripting attacks.

A CGI proxy also protects against distributed denial-of-service (DDoS) attacks by redistributing HTTP requests among different backend servers. It activates different CGI scripts to send traffic to a less crowded server, which denies the possibility of targeting one server and taking it down. DDoS often uses botnets to overload web servers with fake data requests, which is not possible using CGI proxy traffic redistribution.

However, it's worth noting that CGI proxy is only designed to protect web servers, external programs, and databases. Because it is server-side competent, it does not offer client-side cybersecurity features, such as IP address obfuscation for an additional layer of anonymity, local network content filtering, or access restriction to malicious websites.

Advantages and Disadvantages of Using CGI Proxies

Although each advantage has setbacks, they are eliminated if CGI proxies are configured well. For example, a senior cybersecurity specialist will easily implement required security features and protect proxies from downtime. Meanwhile, additional costs are well worth the effort if the website ranks better on search engines, drawing more traffic and revenue.

How to Set Up a CGI Proxy?

The process of setting up CGI proxies differs per provider, web server type, and required features. However, we can issue general guidelines that will outline the essential aspects when deploying them to use.

1. Choose a web server type, like Nginx, Apache, and the like.

2. Configure the chosen server to support CGI scripts and proxies.

3. Write scripts in selected programming languages. You must "inform" CGI proxies how to handle different requests and where to forward them.

4. Test the server by sending HTTP requests that include CGI scripts that fetch data from external databases or redistribute traffic between multiple backend servers.

Additionally, you should consider required cybersecurity features, like SQL injection or DDoS protection. If you expect your website to grow, make sure your proxies are scalable, and CGI script code is optimized for speedy information exchange.

Final Words

Although considered outdated by some, CGI technology will remain an inseparable part of the modern World Wide Web structure for the foreseeable future. Alternatives that run on Python or utilize Node.js are becoming more popular, but switching to them takes time, experience, effort, and money. If your business has a digital presence, you are likely to encounter CGI technology and proxies.

We'd like to remind you that CGI proxies are server-side components, so they don't provide access to geo-blocked content or add an additional layer of online anonymity. However, they efficiently reduce server load, increase website loading speed, and protect from multiple cyberattacks. Knowing what proxies meet your personal or business demands will help you choose the correct type.