designing the DNS from the scratch

[Reindl Harald]

Am 09.07.2017 um 09:31 schrieb Abdulhadi Ettwejiri:
> we are ISP company , we are providing Internet to our customer, Recently 
> one of our VIP customer ask for DNS service, and need the response time 
> 3msec, we don't have enough knowledge of DNS,
> 
> 
>       1-To achieve the goal of my customer about the response time I
>       need to know what’s the optimal design solution for DNS (
>       Authoritative or Recursive(,or there is other design.

that question is wrong from the begin and it depends *what* type of dns 
service

if you provide just resolvers for your customer using on his computers 
as resolver it's a recursive (and no recursive server these days should 
answer to the whole internet because of amplification attacks)

if you want to host the nameserver for your customers domains it's 
authoritative

> 2-If the answer in the previous question an “authoritative”, is there 
> any registration & technical requirements for so (i.e. ccTLD, …   )
a domain points to nameservers, on the machine hosting the nameservers 
you have open port 53 TUDP *and* TCP and the zone needs to be setup

here you go:
https://www.iana.org/help/nameserver-requirements