OpenDNS, NortonDNS and ClearCloud Filter Malicious Domains

David Glosser’s posting on the Malware Domain Blocklist blog reminded me that Sunbelt Software launched the ClearCloud DNS service that filters malicious domains. As David noted, ClearCloud is similar in its capabilities to Symantec’s NortonDNS service. The service that actually defined this space is OpenDNS, which by now is a very mature offering. There is also Google Public DNS, which, unlike the other 3, does not seem to filter known malicious domains, though it provides some other security benefits.

I’m glad to see the increasing availability of security solutions that are:

  • Easy to set up: while client software may be available, it’s not even necessary
  • Easy to use: the user does not need to do anything to maintain the service’s effectiveness
  • Affordable: the services are available for free
  • Efficient: the protection occurs in the provider’s cloud

We need more security tools that are easy to set up and use, that are cheap, and that don’t slow down our systems.

Of course, these DNS-based security services aren’t going to solve all our IT security woes. But they reach into the areas that are often left without protection at all: people and companies that don’t care or don’t have the ability to protect systems with more sophisticated, multi-layered defenses.

Lenny Zeltser


About the Author

Lenny Zeltser develops products and programs that use security to achieve business results. He is the CISO at Axonius and Faculty Fellow at SANS Institute. Lenny has been leading efforts to establish resilient security practices and solve hard security problems for over two decades. A respected author and practitioner, he has been advancing tradecraft and contributing to the community. His insights build upon real-world experience, a Computer Science degree from the University of Pennsylvania, and an MBA degree from MIT Sloan.

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