DNS Coach

Coach DNS is back to answer your toughest DNS questions!
This week, you wanted to know: Why is IP Anycast better than Unicast DNS?

  • Simply put, Unicast is a one-to-one association between network address and network endpoint. If one of these servers goes down, 1/3 of your queries are going to be dropped because that server is no longer available on your network.
  • But Anycast uses one-to-many association where each name server IP corresponds to hundreds of systems world-wide. DNS queries are sent to the closest name server to the client, so speeds are faster and more can be customized per locale. With multiple networks dynamically responding to the same IP address, network performance and uptime are drastically increased.