https://developers.google.com/speed/public-dns/docs/using#configure_your_network_settings_to_use_google_public_dns
https://www.opendns.com/setupguide/
http://superuser.com/questions/114880/should-i-use-google-public-dns-service-for-my-desktop
http://superuser.com/questions/424934/what-are-the-pros-and-cons-of-using-an-alternative-dns-instead-of-the-isp-dns-se
http://www.howtogeek.com/167239/7-reasons-to-use-a-third-party-dns-service/
https://www.doileak.com/blog-DNS%20Server%20for%20privacy.html
