If you want to become anonymous on the web, then you can use something called Tor (The Onion Router). To take advantage of this anonymity, you need to download the software which works together with a volunteer network of computers. The Tor network then disguises your identity by moving your traffic across different Tor servers, and encrypting that traffic so it can't be traced back to you. If anybody tries to snoop on your traffic, they would just see traffic coming from random exit nodes on the Tor network, rather than your computer.
So what is a Tor exit node? That's what I wanted to know, here's what I found out in a nutshell:
A Tor exit Node is the final node that Tor traffic is routed through before it reaches its final destination, i.e. the website that you wish to browse. As such, the IP address of the exit node is taken as the source of traffic, which could include any malicious traffic, in which case the exit node may have to take the blame for any wrongdoing.
So that's a definition of a Tor exit node, let's look at what a Tor node is, what Tor is used for and finally I'll talk about the safety aspect of Tor.
What is a Tor node?
Tor nodes are also called "routers" or "relays" and their job is to simply pass traffic along to the next node in the network. In addition to the exit node that I've just talked about, there are some other types of relays that make the whole Tor network work. These are middle relays and bridges.
In order to anonymize traffic on the Tor network, traffic is passed through at least three of these nodes. So, traffic is first routed through two middle relays, each of which help speed up the network and make it more robust. Once the traffic is routed through these middle relays it is then routed to the final exit relay or node.
So, the moral of the story is, if you ever wanted to do your bit for the Tor network, then it's best to provide a middle relay. That way, the IP address of your middle relay wouldn't show up as the source of traffic, even if a bad actor was to use the Tor network and your middle relay for nefarious purposes.
Bridges are also Tor relays but they aren't publicly listed on the network and they serve as alternative entry points to the Tor network. By using a bridge, you can make it more difficult (but not impossible) for your Internet Service Provider (ISP) to know that you're actually using Tor.
These Bridges are used by people in countries like China for example where the IP addresses of all publically known Tor relays are black listed.
What is a Tor used for?
Tor is short for The Onion Router (hence the logo) and was initially a worldwide network of servers developed with the US Navy to help people browse the Internet anonymously. Today, it's a not for profit organization whose main purpose is to research and develop online privacy tools.
There's a whole bunch of reasons people use Tor but can be useful to anyone that wishes to keep their Internet activities anonymous and out of the hands of advertisers, ISPs and websites that wish to track to. People use it to get around censorship restrictions in their country, police officers use it to hide their IP addresses and generally anyone that doesn't want their browsing habits linked to them.
Tor isn't just about browsing the Internet anonymously, it can also be used to host websites and Web services that can only be accessed via Tor and can't be reached by traditional search engines.
This is the dark side to Tor and what is known as the Dark Web. There are services on there for arms trading, traffic drugs and is generally seen as a hiding place for all sorts of criminal activity.
So be careful if you do decide to go onto the Dark Web.
Is it safe?
Well it depends what you mean by 'safe'. The Tor browser is absolutely safe to use and download. Also, if you're using it for the basic function of hiding your online identity or using it in place of a VPN so that you can access content not available in your country, then you should be okay.
However, if you intend to use Tor to access the Dark Web, then you could end up getting more than you bargained for.
What this means is that the Dark Web is the portion of the Internet that is often used for illegal activities such as child pornography, the sale of drugs, prostitution, etc. The Tor software is required to access the Dark Web, so it goes without saying that using the software could lead you into some pretty dark places.
Now if you consider the word 'safe' to mean totally anonymous, then Tor cannot completely guarantee this.
Tor isn’t the perfect anonymity and privacy solution. Granted it does achieve anonymity by passing encrypted traffic through the network, but your traffic has to come out somewhere and at some point will hit the visible web via a Tor exit node.
So to sum up then, if you're using Tor to hide yourself from advertisers and marketers, then Tor can be a useful tool. However, if you use it to access the Dark Web and to access some of Tor's hidden services, then be careful what you click. There's no doubt that a lot of the content is made up and some of the services are traps designed to catch people buying illegal services, but there is some horrific stuff on there (as well as the visible web), you've been warned ;)