https://blog.wongcw.com/2018/10/14/icann%e5%8d%b3%e5%b0%86%e4%b8%badns%e7%b3%bb%e7%bb%9f%e6%9b%b4%e6%8d%a2%e5%8a%a0%e5%af%86%e5%af%86%e9%92%a5-%e4%bd%86%e5%8f%aa%e4%bc%9a%e5%be%88%e8%bd%bb%e5%be%ae%e5%bd%b1%e5%93%8d%e5%88%b0%e4%bd%a0/