DNS Filtering: Why Do You Need It And What’s The Best Approach?

Our lives would be unimaginable without the internet. However, it is also home to a wide range of harmful content, ranging from malware to phishing scams. Malicious web actors hold the potential to harm our devices and compromise our personal information. As a result, many organizations are turning to DNS filtering to mitigate these risks.


Let’s take a deep dive into understanding what DNS-layer security is, why businesses need DNS security and DNS filtering, and what are the multiple approaches to DNS filtering.

Why Does Your Business Need DNS Security?

A report by the Ponemon Institute found that 54% of organizations have experienced one or more DNS attacks in 2021-22.

DNS security refers to the measures put in place to protect the Domain Name System (DNS) from various cyber threats, such as phishing attacks, malware, DDoS attacks, and other forms of cybercrime.

DNS is a critical component of the internet infrastructure. It is responsible for translating domain names into IP addresses, allowing computers to communicate with each other over the internet. As a result, DNS security is essential to ensure the reliability and safety of the internet.

DNS Security is Vital for Several Reasons:

  • Protecting against phishing attacks

DNS security measures such as Domain Name System Security Extensions (DNSSEC) can help prevent phishing attacks. It ensures that users are directed to the correct website, not a fake site designed to steal personal or financial information.

  • Preventing malware infections

DNS security measures can also prevent malware infections by blocking access to malicious websites or redirecting users to a safe website. This can help prevent the spread of malware across a network.

  • Ensuring the availability of websites

DDoS attacks can overwhelm DNS servers, causing websites to become unavailable. DNS security measures such as rate limiting, and traffic filtering can help prevent DDoS attacks and ensure the availability of websites.

  • Protecting against DNS cache poisoning

DNS cache poisoning is a technique attackers use to replace legitimate DNS entries with malicious ones, redirecting users to fake websites. DNS security measures such as DNSSEC and DNS over HTTPS (DoH) can help prevent DNS cache poisoning attacks.

  • Safeguarding the integrity of the DNS system

DNS security measures can also protect the integrity of the DNS system by preventing unauthorized changes to DNS records, ensuring that DNS servers are secure, and preventing DNS hijacking.

DNS security is essential for ensuring the reliability, availability, and security of internet-based resources. With the increasing number of cyber threats and attacks targeting the DNS system, it is more important than ever to implement DNS security measures to protect against these threats and ensure the integrity of the internet infrastructure.

What is DNS Filtering?

DNS filtering blocks or allows access to websites based on their domain names. Domain Name System (DNS) is a protocol that translates domain names into IP addresses, making it possible for devices to communicate with each other over the internet. DNS filtering works by intercepting DNS requests. It either redirects them to a different IP address or blocks them altogether. 

DNS Filtering vs. URL Filtering

URLs are the addresses that are used to access specific pages on a website. URL filtering is a means of blocking or allowing access to websites based on their URLs. Unlike DNS filtering, which blocks access to entire domains, URL filtering can block specific pages or sections of a website.

While DNS filtering is often used to block malicious content, URL filtering is more commonly used to block access to inappropriate or distracting content, such as social media or gaming websites.

Organizational Benefits of DNS Filtering

DNS filtering has very relevant benefits for organizations. It’s an essential weapon to have in your cybersecurity arsenal. The multi-dimensional use cases of DNS filtering extend its usefulness beyond blocking harmful content. In today’s corporate culture, robust DNS filtering rules and web access policies directly impact an organization’s overall productivity and reputation.

Let’s explore three essential benefits of DNS filtering:

  • Protection against rampant cyber threats 

DNS filtering can help protect businesses from cyber threats such as malware, Ransomware, phishing attacks, and other types of cybercrime. According to a report by Verizon, 94% of malware is delivered via email, and phishing attacks are the most common cause of data breaches. DNS filtering can help prevent users from accessing malicious websites and downloading malware, reducing the risk of cyber-attacks.

  • Boosting team productivity and focus

DNS filtering can also help improve employee productivity by preventing access to non-work-related websites and reducing the risk of distractions. According to a recent study, the average employee spends about 2 hours daily on non-work-related websites, which can significantly impact productivity. DNS filtering can help reduce employees’ time on non-work-related websites, thereby improving productivity.

  • Ensuring regulatory compliance

DNS filtering can also help businesses ensure compliance with regulations such as the Children’s Online Privacy Protection Act (COPPA) and the Health Insurance Portability and Accountability Act (HIPAA). For example, COPPA requires websites to obtain parental consent before collecting personal information from children under 13, while HIPAA requires healthcare providers to protect the privacy and security of patient information. DNS filtering can help businesses ensure compliance with these regulations by preventing access to non-compliant websites and blocking the transmission of sensitive data.

Suggested reading: DNS Filtering – A Comprehensive Guide

3 Essential DNS Filtering Approaches to Know

DNS Filtering can take multiple approaches. Here are the popular ways DNS security and filters are implemented across industries:

Approach 1: Policy-based DNS Filtering

Policy-based DNS filtering is a method of controlling website access based on pre-defined policies. These policies can be customized to meet the specific needs of an organization. For example, a company might want to block access to social media sites during work hours but allow access during lunch breaks. Policy-based DNS filtering can also block access to malicious websites based on their reputation or category, such as phishing or malware-coded websites.

Policy-based DNS filtering is often implemented using a DNS firewall or a DNS filtering service. These services are configured to block website access based on a set of pre-defined policies. The advantage of policy-based DNS filtering is that it allows organizations to have granular control over website access. However, defining policies and keeping them current requires a lot of time and effort.

Approach 2: DNS Sink-holing

DNS sink-holing is a method of redirecting DNS requests to a non-existent or “blackhole” IP address. This method is often used to block access to malicious websites. When a user tries to access a malicious website, the DNS request is intercepted and redirected to a blackhole IP address. As a result, the user is unable to access the website.

DNS sink-holing is often implemented using a DNS server configured to redirect requests to a blackhole IP address. The advantage of DNS sink-holing is that it can be used to block access to a large number of malicious websites without the need for pre-defined policies. However, it is less effective against more sophisticated attacks, such as those that use domain generation algorithms to create new domains.

Approach 3: DNS Filtering with Machine Learning

DNS filtering with machine learning is a method of blocking access to websites based on their content. This method uses machine learning algorithms to analyze website content and determine whether it is malicious. The advantage of leveraging machine learning is that it can identify new and previously unknown threats that other methods might miss.

DNS filtering with machine learning is often implemented using a cloud-based service that uses machine learning algorithms to analyze website content in real time. The service can be configured to block access to websites based on their reputation or category, such as phishing or malware websites. The advantage of DNS filtering with machine learning is that it can be highly effective against new and emerging threats. However, it requires significant computing power and can be expensive to implement.

As a Closing Note 

In conclusion, DNS filtering has become essential for businesses to enhance their overall cybersecurity posture. The technology helps prevent access to malicious websites, blocks malware from communicating with command-and-control servers, and ultimately safeguards your organization’s network from crippling cyber threats.

With its highly customizable settings and flexible deployment options, Ace Managed DNS Filtering offers businesses an unmatched level of control over their DNS security. This solution is ideal for organizations of all sizes that require a comprehensive and highly effective cybersecurity solution to protect their network from a wide range of cyber threats. Its advanced features and functionality can leave even the most perplexed cybercriminals scratching their heads in defeat.

About Nolan Foster

With 20+ years of expertise in building cloud-native services and security solutions, Nolan Foster spearheads Public Cloud and Managed Security Services at Ace Cloud Hosting. He is well versed in the dynamic trends of cloud computing and cybersecurity.
Foster offers expert consultations for empowering cloud infrastructure with customized solutions and comprehensive managed security.

Find Nolan Foster on:

Leave a Reply

Your email address will not be published. Required fields are marked *


Copy link