VPN and proxies – What are they?

Virtual Private Network (VPN) and proxies are data encapsulation software that does IP encapsulation in either Layer 2 or Layer 3 or maybe even both. VPNs and proxies are often used for bypassing firewall restrictions, anonymity, access Intranets of certain organisations and visiting websites that are blocked by your ISP.

So how do they work? After the packet data from Layer 3 is ready to be sent, the packet will be encapsulated with the VPN’s IP address before proceeding to Layer 2. This will hide your computer’s real IP address but if you’re using a proxy, there might be headers (X-Forwarded-For) which are sent to reveal your IP address. This is done for some public proxies to prevent abuse from users. If the data exchange link between the VPN/proxy and computer is encrypted, Firewalls will not be able to look through the data to detect and block certain content. This is especially useful if you’re using China’s networks which are filtered and blocked by the Great Firewall of China (Golden Shield Project) or if you’re within a school or campus network. Proxies are also mostly limited for web browsing usage due to limited support from program developers. For example, most games with multiplayer cannot be run through a proxy.

There are many opensource VPN projects such as SoftEther, OpenVPN, Tinc, StrongSwan and many more while proxy software include but are not limited to ShadowSocks and Glype. These software requires a server and needs to be setup and configured by a person with some knowledge in networking. However, there are many free open proxies which do not require any setup. One of the most famous free and open proxy would be Tor and another one would be I2P.

Tor was started out as a project by the USA Navy and funded by the US government to allow complex encrypted communications within the government officials, officers and the US Army. It became a even more popular tool after Edward Snowden’s whistle blowing in 2013. He recommended the use of Tor and PGP to protect users’ privacy. Security wise, it’s possible to reveal your IP address while connecting through Tor if, and only if you did not disable Javascript and you visit a website that uses certain Javascript code that can reveal your IP address. Therefore, many steps and actions are required to fully protect your anonymity while surfing on the Tor network. Both the American and Russian government has also invested a lot of money into decrypting the Tor network. As of now, Tor is still “unbreakable”. Besides all these political drama, Tor is notorious for being misused by a lot of users to launch large scale Distributed Denial of Service attacks, browse child pornography, buy illegal drugs online and even offer assassination services.

In conclusion, VPN and proxy services are very useful and helpful tools that enables people from China to reach out to the world behind the Great Firewall of China. However, it is also a very destructive tool if abused by evil people with evil intentions.

Author: Huiren

I use free software and sometimes contribute to free software. I write about mostly technical problems I face and how I overcome them

6 thoughts on “VPN and proxies – What are they?”

  1. Hi Huiren

    Appreciate your post here. Would like to check with you on the following:
    1. Let’s say we are using a public computer and we plug in USB thumbdrive with TOR installed and browse the website, are we able to have access to gmail/facebook if the computer has disallowed access to gmail/facebook?
    2. Will the adminstrator of the computer be able to track what we have browsed with TOR on thumbdrive?

    Thanks.

    1. 1) Yes.

      2) On the network level, no, its not possible as long as you have WebRTC and Javascript disabled on your browser. Make sure you delete your browser history and make sure there are no screen monitoring tools. Some big companies have screen monitoring tools that takes screenshot of all their employees’ screen every few 30 seconds or so.

      1. Thanks for the reply. So do you mean we have to disable WebRTC and Javascript on TOR browser settings? And after which, we delete TOR browser history?

        1. Yes. You can use NoScript which effectively disables Javascript or disable Javascript through the browser settings.

          WebRTC can be disabled in the browser settings.

  2. Thanks once again. Can you also elaborate on the difference between VPS and VPN?
    So we can’t install programs on VPN but we can do it on VPS?

    1. A VPS is a virtual private server. A big server is virtualized using virtualisation technologies such as KVM and the product of this virtualisation would be many small VPS.
      The performance of your VPS depends on who your hosting provider is and how much resources your are allocated to for your VPS. This is because some hosting providers overload their big servers with too many small VPS. You can read more about what a VPS is on Wikipedia – http://en.wikipedia.org/wiki/Virtual_private_server

      A VPN is a virtual private network. It is related to networking and has nothing to do with virtualisation technologies. VPN softwares provides IPSec encryption for your data. You can read more about what a VPN is on Wikipedia – http://en.wikipedia.org/wiki/Virtual_private_network and what IPSec is – http://en.wikipedia.org/wiki/IPsec

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