[Anunayj]

Well there are a couple of ways one can do this!

1. Recursively lookup DNS, so domains will have to be blocked at the registrar level, since DNS is unencrypted, it can be blocked at ISP level as well.

2. Use a protocol alternative to DNS, a good mature example is GNS. It aims to replace DNS, with a built from group up, modernish protocol. Using a DHT and public-key cryptography.

3. There are "block chain" solutions to the whole domain problem, look at Handshake, ENS etc.