OpenDNS

OpenDNS, now a part of Cisco, was a company that provided domain name system (DNS) resolution services with security features. Founded in 2006, OpenDNS offered a free and paid service that functioned as an alternative to the DNS servers provided by internet service providers (ISPs).

The core function of OpenDNS was to translate human-readable domain names (like example.com) into IP addresses that computers use to locate each other on the internet. However, OpenDNS distinguished itself through additional services, including:

• Phishing Protection: OpenDNS filtered malicious websites known for phishing attacks, preventing users from unknowingly entering their credentials on fraudulent sites.
• Malware Blocking: The service blocked access to websites distributing malware, helping to prevent infections.
• Content Filtering: OpenDNS allowed users to configure content filtering rules, blocking access to certain categories of websites, such as adult content or social media. This was particularly useful for parents seeking to protect their children online.
• Typosquatting Protection: OpenDNS offered protection against typosquatting, where users are redirected to malicious websites due to common misspellings of popular domain names.
• DNSCrypt Protocol Support: OpenDNS supported DNSCrypt, a protocol that encrypts DNS traffic between the user's computer and the OpenDNS servers, improving privacy.

OpenDNS offered both free and paid services. The free service provided basic security features, while the paid service offered more advanced features, such as detailed reporting, whitelisting and blacklisting of specific domains, and priority support. The paid services targeted businesses and educational institutions.

Cisco acquired OpenDNS in 2015. While the OpenDNS name is still used, the technology and services are now integrated into Cisco's security portfolio and often branded under the Cisco Umbrella name, particularly concerning enterprise-level security. The core function of providing DNS resolution with added security remains the same.