DNS
From Cship
The Domain Name System (DNS) resolves domain names to IP-adresses.
Every computer on the Internet has an unique address (a little bit like a telephone number). These are 4 numbers from 0 to 255 separated with a dot, for example 85.13.138.4 is the IP-address for cship.org.
Because of remembering such a number is very difficult the DNS was invented. This service maps an URL to it it's IP-address. If you type cship.org into your browser the request is send to the DNS-server that was automatically given to you by your ISP on dialing into the Internet. A lot of addresses are already cached so the DNS-server sends the IP-address for the URL back to you. If the DNS-server has no cached information on the site requested by you he asks one of the 13 root servers which know all addresses. If the DNS server from your provider is censoring he just refuse to send you the real IP-address; he sends you nothing or an IP from a "sorry" website.
This is used for example from some german providers. It is a very cheap and easy censoring method and the same is true for bypassing it. To bypass this censorship method you can use another DNS server or try almost all other bypass methods.
It is possible to tunnel almost everything over a DNS tunnel.
[edit] Public DNS servers from OpenDNS:
- 208.67.222.222 (resolver1.opendns.org)
- 208.67.220.220 (resolver2.opendns.org)
- instructions to use
[edit] Public DNS servers from the ORSN network:
- 217.146.139.5 (ns1.de.eu.orsn.net)
- 62.157.101.211 (resolver.data-union.net)
- instructions to use
