18/01/2012 § Hinterlasse einen Kommentar
Due to #SOPA and #PIPA (or similar pieces of legislation), it could be that the United States government (or any other government) will (one day) enforce blocking diverse DNS-entries – and even outlaw the information on how to circumvent those blockades.
Since it is unlikely that I’ll visit the US again in this lifetime, I shall put this information up without much risk. Of course, WordPress is based in the US, so this information is only half secure. Read it. Copy it. Prepare yourself.
Anyway, here it is:
How to circumvent DNS blockades
What follows is the content of the article: „What is a DNS block and 3 ways to get around it“ by blogjunkie.net
Recently the Malaysian Commission for Multimedia and Communications (MCMC) issued a directive to local ISPs to filter a number of file sharing websites because they violate the Copyright Act. While some of the content may be in violation of the Act, some think the Government is being too heavy handed by issuing a blanket order to block these sites.
I don’t want to debate the Government’s decision, but I believe that sometimes there are legitimate reasons to access websites that your Government / ISP / employer doesn’t want you to. This article will explain what is DNS filtering and show you 3 ways to get around it.
What is DNS blocking?
DNS blocking or filtering is a common method of denying access to certain websites. Let’s have a look at how it works.
Each website is hosted on a web server that has a IP address. For example, the IP address for Facebook is 188.8.131.52. If you type those numbers in your web browser, you will arrive at Facebook’s website. Try it – http://184.108.40.206/.
However, IP addresses are not very user friendly. It’s easier to remember facebook.com than 220.127.116.11 isn’t it? Therefore the inventors of the internet also created a phone book called the Domain Name System, or DNS.
The DNS translates domain names into IP addresses so that you don’t have to remember random strings of numbers. Each ISP (e.g. Streamyx, P1, etc) have their own DNS servers that functions as phone books for their subscribers.
Whenever you type a website address into your browser, your browser first asks the ISP’s phone book what the IP address for that website. Once it’s figured out the IP address it will then load the website for you.
With DNS blocking, the ISP is simply removing the record for the blocked websites from their phone book. So when you try to load one of the blocked websites, all you get is a blank screen in your browser because it doesn’t know what the IP address is.
3 ways to get around DNS blocking
1. Use another DNS server / phone book
What do you do if your phone book doesn’t contain the address you are looking for? You use another phone book!
Besides your ISP, other organizations also offer DNS servers. One such organization is Google. You can manually tell your computer to refer to Google’s DNS servers – 18.104.22.168 and 22.214.171.124 – and it should now be able to access the blocked sites again (unless Google also blocks them).
Google has detailed instructions on how to tell your Windows, Mac or Linux computer to use their DNS. For iPhone users, you can go to the Settings app » Wi-Fi Networks » tap the blue arrow for your current Wi-Fi network » type 126.96.36.199 in the DNS field.
2. Use a Proxy server
A proxy server is a server that acts as an intermediary, relaying your request for connection to a webpage, file, or service on the Internet. It gets you around the DNS block because the proxy server should not rely on our local ISP’s DNS servers (phone books).
The downside to using a proxy is that all your passwords, cookie information, etc is being relayed though the intermediary. However if trying to access file sharing websites it’s probably not too much of a security concern.
There are many public proxy servers available – just try Googling for ‘free proxy server’. However many of the free ones plaster you with ads in return for their service. I have found a really good one with no ads at http://labnol-proxy-server.appspot.com/.
The proxy server above is created with Google App Engine. The creator even has a tutorial to show you how to make your own proxy server (188.8.131.52).
Addendum: Find out IP-Addresses: What is the IP Address(es) of websiteipaddress.com?
The IP address(es) of websiteipaddress.com: 184.108.40.206
3. Use a VPN
A VPN is a secure connection from your computer to another computer or server. It works in pretty much the same way as a proxy sever, but it’s more secure. The TUVPN blog has a post that explains the differences between VPN and proxy servers.
The important thing is that using a VPN will also bypass the DNS block. If you only need to bypass these DNS blocks occasionally, Hotspot Shield is a free VPN service that you can use. It works for both Mac and PC and is a usable solution – just be prepared for the ads.
With great power comes great responsibility
I do not condone piracy. I believe that you should pay the content producers to support their work. The main reason I use VPNs is to get around Amazon.com’s geographic restrictions to buy digital content. Yes, I bypass filtering so that I can pay for content!
My guide here is to empower you with the knowledge to get around censorship from your government, ISP or employer if there are legitimate reasons for it. Use your knowledge wisely and responsibly!
Oops: No DNS-blocking in SOPA or PIPA any more
But anyway: What the US wanted now, anyone could want tomorrow.
So remember this, and copy it, and be prepared.