December 10, 2020

What Is a DNS Filter & How Is It Used?

GoGuardian Team
A illustration of two children sitting on top of a computer screen holding laptops. A lap top and smart phone are on each side of the computer monitor.

Guarding digital footprints while online is a collective responsibility. For instance, if you have a business website that customers log in to every day, you must guarantee the data security and privacy.

Because data privacy has become a sensitive issue with advancing technology, most companies and individuals are adopting the most effective ways to combat breaches. These include using DNS filters to protect devices and networks from hacking, malware, viruses, and cybercrime.

Many myths surround the usage of DNS filters for blocking malicious websites and protecting devices from external harm. For example, some people believe that there is no need to have a DNS filter for your network if you already have an antivirus.

In this article, we debunk the myths and misconceptions about DNS filtering and discuss the benefits of using an open DNS content filter in your school network.

What Is a DNS Filter?

The Domain Name System (DNS) is like a universal phonebook for the web. It is responsible for translating a URL to a language that computers understand.

When you insert a URL on a browser, the DNS changes the words into numbers that a computer can understand, known as an IP address. Your browser then displays the information found at that address. It is not easy to remember the numbers of IP addresses, so DNS translates them to common words.

A DNS filter blocks a website that it believes to be a threat to its users. The website could be hosting harmful content or be created by hackers to steal sensitive information from users.

DNS filtering is a process of blocking access to all websites that have been deemed a threat. A DNS filter blocks a website's IP address so that it is not available when users click on its link on search engines. Most websites that fall into a DNS filters' jaws include gambling, adult content, torrenting sites, and other productivity sinks.

Every business needs a dedicated DNS filter to remain secure online and protect its information system from data loss and cybercrime. Networks can be exposed to threats like viruses and malware, but with a DNS filter, you can significantly reduce the risk of cyber threats. With a dedicated DNS filter, you can block up to 88 percent of malware on the internet from reaching your network.

How DNS Filtering Works

When building your website, you have to purchase a domain name from a domain name registry to host your site on the internet. This domain name acts as your internet address. When users want to find your website online, they must enter the domain name, or URL, in their browser and wait for your website to load.

This is where DNS filtering comes in. The DNS looks up your IP address and connects a browser to a web server to obtain the information you are looking for. This process often takes just seconds. The web page is loaded on the screen once the browser connects to the web server.

When DNS filtering happens, your browser is blocked from connecting to web servers and relaying the information a user is searching for. This happens when a website is suspected to be malicious or fraudulent or is otherwise blocked by your network administrator. Any request to connect to a malicious website is subjected to controls, helping to ensure a network is safe from threats.

A DNS maintains an updated list of malicious websites in real-time. When a user tries to access a website blocked by DNS filters, they are redirected to a local IP address explaining why they cannot connect to the website.

Controlling access to malicious websites is possible via your Internet Service Provider (ISP), at the router level, or through a web filtering provider. You can list websites that you believe are harmful to your network in the filter, and it will prevent access to those websites. Having an open DNS web filter helps protect your network from cyber attacks that can result in data loss.

It is important for schools and other institutions to opt for DNS filtering to block access to a category of websites like pornography, adult content, gambling, and gaming. It helps you keep students focused when using the internet in class.

Can You Bypass an Open DNS Filter?

A simple answer to this question is yes. You can bypass an open DNS filter. When you ask your ISP or web filtering provider to filter internet connection, some of your users may still find a way to bypass the DNS and access malicious websites. Be sure to guard against these proven ways that people use to bypass DNS filters:

  • Installing a VPN in the browser: There are many Virtual Private Networks (VPNs) that can be installed on a browser to bypass restrictions. A VPN guarantees unrestricted access to all websites, including adult content or streaming content not permitted in your country.
  • Using DNS servers to bypass regional blocking: Your ISP normally sets a DNS server in your settings every time you connect to a network. That means to access a restricted website, users can manually set their connection to a DNS server that bypasses filtering.
  • Proxy servers: Users can bypass a content filter using a proxy server, although it may not be as reliable as a premium VPN.
  • Fix with a URL shortener: In some cases, you can trick your browser into thinking that you are accessing a different website by simply shortening the URL of a blocked website. If the URL shortener redirects to a different website, you may still be blocked in the process of accessing the site.

Why Do You Need a DNS Filter?

If your network keeps growing, you may need a DNS filter for automatic scaling GoGuardian provides the best DNS filter that helps you scale your network and make it more efficient for hundreds of users accessing it in real-time. It also enables you to offer basic filtering for BYOD guests and staff.

For schools, a reliable DNS filter is essential to ensure that students don't access illegal or malicious websites while on the school network. Of students that browsed with a GoGuardian device: The average student attempts to visit 57 flagged websites per month and 12 blocked websites per month. You can manage how your staff and students access the internet at a granular level so that you protect your organization network from external threats that can result in data loss.

Bottom Line

DNS filtering is useful for any organization looking to prevent data breaches and attacks by malware. With a reliable DNS filter for your network, you can stop users from accessing and downloading malware that could harm your systems. Get the best DNS filtering system for your school from GoGuardian.