The Domain Name System (DNS) protocol is an important part of the web’s infrastructure, serving as the Internet’s phone book: every time you visit a website, your computer performs a DNS lookup. Complex pages often require multiple DNS lookups before they start loading, so your computer may be performing hundreds of lookups a day.
https://www.opendns.com/home-internet-security/
DNS nameservers are always: 208.67.222.222 208.67.220.220
Aug. 27, 2015 – Cisco (NASDAQ: CSCO) today announced it has completed the acquisition of OpenDNS http://www.cisco.com/c/en/us/about/corporate-strategy-office/acquisitions/opendns.html
Google Public DNS
https://developers.google.com/speed/public-dns/
Configure your network settings to use the IP addresses 8.8.8.8 and 8.8.4.4 as your DNS servers.
origin - http://www.pipiscrew.com/2017/08/opendns-and-google-public-dns/ opendns-and-google-public-dns