Hosting your own DNS servers usually means that all queries will be resolved from a single physical location. If a visitor far from your DNS server is trying to access your website, the DNS response can take a while to reach them. If your DNS server malfunctions or becomes unavailable for some reason your internet site or services will be inaccessible.
Devices connected to the Internet or any other network use an IP address to send data to each other. End users who want to visit your web site types URL (i.e. www.google.com) in browsers instead of an IP address. DNS translates the domain name into the IP address of the website. Once you have found the IP address, your computer can connect to the web server and the web page is displayed. When an end user in the UK tries to access your website in Turkey, DNS response will take a little longer to return.
In Anycast, a server cluster shares the same IP address. Your website's DNS information is copied to the Altosec servers at different locations around the world. Anycast DNS allows to direct the request as close as possible. Your visitors automatically receive information from the nearest location to ensure fastest loading time and also lower latency.
Here is an example to make it clear. You need to get medicine from a pharmacy. You search the address of a pharmacy in the GPS navigation app on your mobile phone. The app will take you to your nearest pharmacy. If the road is closed, it will reroute you to the next closest pharmacy.
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