Tor encrypts your data and protects you by bouncing your communications round a distributed network of volunteer relays. The idea is that these volunteers protect you because they don’t know who or where you are. And the best part is, it’s totally free and open-source software!
In this post, we’ll explore some of the lesser-known aspects of Tor, with 10 facts that will make you an expert in all things onion routing. Let’s get started!
- You can use Tor to share sensitive information
The Tor Project was created to help political activists share information without fear of censorship from oppressive governments that might block certain websites for their citizens. It was funded primarily by the U.S. Government through the U.S. Naval Research Laboratory and the Electronic Frontier Foundation. Tor was originally known as The Onion Routing project since it encrypts your data in layers like an onion, each layer of encryption being peeled away with every relay until it reaches its destination (the core Tor client is called Vidalia ).
Tor can also be used for general privacy and anonymity by anyone who wishes to improve their safety when browsing the web, using instant messaging services, or communicating over other mediums that you might not want eavesdroppers listening in on.
- You can use Tor to access blocked websites
Thanks to the decentralized network of volunteer relays, Tor is currently the best way to navigate around censorship and website blocking. Great examples of situations where this may be useful include: – A human rights activist in Iran who wishes to discuss government corruption with other dissidents – An American student who wants access to certain educational or research materials that are blocked by their university’s internet policies – A Chinese citizen who wants to search for information about democracy and other issues banned by their government Tor can also provide a safe haven for people living under oppressive regimes, though this is not always true .
At the time of writing, the Tor network has only 16 active exit relays (companies or individuals that accept and forward your connection), but there are over 7,000 entry relays. This means connections may take longer to establish and/or be less reliable than normal.
- You can use Tor even if you have a government-issued internet provider
It’s important to remember that ISPs are not allowed to log any information about users of their service, so they won’t be able to see who you are or where you’re browsing from. Likewise, Internet Service Providers (ISPs) cannot block access to certain websites, like companies or governments might do in countries with repressive regimes (such as China). For companies, the threat of losing paying customers is usually enough to keep them from using active blocking techniques. However, ISPs are legally required to follow government orders to either log your data or restrict access to certain websites. In these situations, a VPN can help protect your anonymity, though it’s not as effective as Tor and it’s more vulnerable to DNS leaks . Using Tor with a VPN might be an effective way to increase security.
- A single onion route can be used multiple times
When you connect to the Tor network, your data is wrapped twice and also encrypted multiple times. Each time your data is wrapped, the next ‘hop’ along the way is chosen randomly. If you connect from country X to country Y, and then another country Z before exiting the Tor network, you would end up having to use many different routes to get out of the network.
To understand this process a little better: Imagine that there’s a box with a number of packets inside of it (we’ll call it a ‘packet’). Each packet has first been encrypted with one key, then additionally wrapped with another key (which we’ll call in this case ‘A’, and which we’ll later refer to as ‘A’). Then each packet is encrypted with a third key (which we’ll call ‘B’), and then wrapped with one more key (which we’ll call in this case ‘B’). Finally, each encryption is applied a fourth time and another key (which we’ll refer to as ‘C’).
Now if you want to get the packet back out, you would need to have all four keys (A, B, C, and D) or three of them in order to retrieve the original packet. However, this also means that there are four possible ways of decrypting any one of the encryption programs. This could mean a complete loss if an attacker were able to obtain all four keys before the decryption process was done.
Keys A, B, C and D are often referred to as a ‘key ring’. As an example, keys A, B, C and D are kept in a key ring that is normally kept in a safe. In order for someone to return the packet to you they would need all four keys or one of them along with their own private key. As long as the private ends up with the correct key ring they can return your packet back to you.
This brings us back to the original idea behind Digital Signatures: You make a digital signature on any data that you want to associate with your name or property (such as a purchase order). So when that data is signed, your private key is returned along with a copy of the signature. In this case the return of the signed data and the encrypted data would both be bundled together in a ‘packet’.
- Tor has its own hidden internet protocol (the onion router)
The Tor network is also known for being an ‘anonymous’ network by using encryption methods other than TCP/IP or IPsec. The Tor onion router uses a specialized version of TCP called SOCKS . Its own custom version of DNS called STUN was created to hide the location of servers offering access to this layer.
- Tor was originally developed for the U.S Navy
Tor was originally developed by the Naval Research Laboratory in response to the Department of Defense’s needs for a method to allow military intelligence employees to communicate securely. Tor is now one of many tools that the Pentagon reportedly uses to help achieve online anonymity and protect their data. The U.S. government also provided grants that helped support privacy-enhancing researchers by helping them find other grants and awards so they could continue working on research. Although Tor began in part with funding from the government, it has since become an open-source project funded solely through donations from nonprofits and companies (including Google).
- Tor is funded by the government and a variety of nonprofits
In addition to being used by millions of individuals, Tor has also been used to create a cell phone version that can be used in countries with repressive regimes. Tor is also funded, in part, by the CIA. The National Science Foundation has given more than $1.8 million to researchers who have been able to help develop and improve the network.
- A number of websites are blocked from being accessible through Tor
Tor is sometimes used in countries with severe censorship to bypass blocked websites or sites that may be known or suspected for having illegal content on them. The Tor network is also used for applications such as web hosting. Some websites have been blocked because their content is considered illegal or harmful by the government. Some countries have blocked Internet Relay Chat (IRC) on the basis of the availability of hidden services and anonymity offered by the Tor network, and many blocking policies have been lifted in recent years as a result of these issues.
- The U.S Army operates its own Tor node
The largest deployment of the Tor network is by users in China who use it to access social media sites such as Facebook, other popular sites, and more that are blocked in China. The U.S Army also has a node to allow their users to connect and send and receive emails through Tor.
- Most European onion routers use the .onion suffix
Almost all of the major onion routers have chosen some form of non-anonymous suffix for the service name and IP address, such as in most cases in .onion or .gnuzilla (for GnuZilla). There are still a few instances of .exit, which is used by only a few networks.
Bonus. Tor hidden services are only available via the Tor network
There are a few known and well-known websites that offer access to content that’s considered illegal or obscene. These sites are typically called “hidden services” (although they can also be accessed via different methods). They’re specified by having the.onion suffix (but not by having a particular server to direct people to). For example, the popular hacking forum HackForum uses .onion in its URL. Some of these sites were actually created before Tor existed, and some of them were created as alternatives to what most people believed should be happening in that type of environment.