
Knowledge base
February 15, 2025
DNS filtering: Protect your Network from Online Threats
Cyber threats are becoming more sophisticated and companies need to take their network security seriously. DNS filtering is a powerful solution that helps block unwanted Web sites and cyber attacks even before they can do damage. But what makes DNS filtering so effective? 🤔
✅ What is DNS Filtering?
DNS filtering is a cloud-based security technology that works at the DNS level. It prevents users from visiting malicious Web sites by analyzing Internet traffic and blocking it where necessary. This provides protection against:
🔹 Phishing – Blocks fraudulent websites trying to steal login credentials.
🔹 Malware & Ransomware – Prevents malicious software from accessing the network.
🔹 Unwanted Content – Filters dangerous or inappropriate websites.
🔹 Zero-day attacks – Detects and blocks new threats in real time.
🚀 Why is DNS Filtering important?
DNS filtering provides proactive protection against cyber threats and has multiple benefits:
🔹 Prevents cyber attacks before they do damage.
🔹 Increases network performance by blocking harmful traffic.
🔹 Provides control and insight into Internet usage within the organization.
🔹 Easy deployment without additional hardware or complex configurations.
🔥 How does DNS Filtering work?
1️⃣ A user tries to access a Web site.
2️⃣ DNS filtering checks the domain against a database of threats.
3️⃣ Harmful websites are blocked, safe sites are allowed through.
4️⃣ Reports and monitoring provide insight into network traffic and threats.
🏆 Advantages over traditional web filters
🔹 AI-driven detection for faster and smarter protection.
🔹 No software installation required – Works at the network and device level.
🔹 Automatic updates against the latest cyber threats.
🌍 Who is DNS Filtering suitable for?
✅ Companies looking to proactively secure their network.
✅ Schools and educational institutions seeking to ensure secure Internet access.
✅ Government agencies complying with data protection regulations.
✅ Managed Service Providers (MSPs) protecting customers from cyber threats.
🔍 What is the difference between DNS Filtering and URL Filtering?
Although both DNS filtering and URL filtering are meant to block malicious Web sites, they work differently.
🔹 DNS filtering works at the domain name system (DNS) level. This means that an entire website (such as malwarewebsite.com) is blocked even before a connection is established. This provides faster and network-wide protection without the need for additional software.
🔹 URL filtering analyzes individual Web addresses (URLs) within a Web site. This means that only certain pages within a domain are blocked, such as malwarewebsite.com/dangerousfile. This allows fine-grained control, but the process is slower and usually requires an additional proxy server or software on the device.
🔹 One important difference: URL filtering can also block domains
With some URL filtering solutions, it is possible to blacklist not only individual pages but also entire domains. This is similar to DNS filtering, but often works slower because the browser first loads part of the Web site before the filtering intervenes. DNS filtering instantly blocks the entire domain name at the network level, which is more efficient and secure.
🚀 What is the best choice?
For most businesses, DNS filtering is the best first line of defense. It provides fast, network-wide protection without additional software. URL filtering can be used as a supplement when specific pages or content within a domain need to be blocked.
🎯 DNS Filtering at ALTA-ICT
At ALTA-ICT, we integrate DNS filtering into our modern workstations¹ to provide businesses with a secure and efficient work environment. Want to know how DNS filtering can protect your organization from cyber threats?
📩 Contact us for more information!
References
¹https://alta-ict.nl/diensten/moderne-werkplek/
About the author
My name is Alta Martes, a specialist in Microsoft 365 and Google Workspace, with a focus on modern workplace management, cloud security and identity & access management. With years of experience, I help organizations optimize their IT infrastructure and create a secure, efficient digital workplace.
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