A peek inside the elusive world of the Dark Web
If you watch crime-related television shows like “CSI: Cyber” or “Criminal Minds," you’ve probably heard of the mysterious and dangerous Dark Web, a place where evil hackers perpetrate their nefarious computer crimes, where shady deeds are done and illegal purchases go down.
Much like “the cloud,” the Dark Web is shorthand for technology that most people really don’t understand very well. The Dark Web isn’t all that different from the regular Web (the “surface web,” as it’s sometimes called). They’re both based on the Internet and the Internet Protocol (IP) that drives it. The difference is the level of anonymity the Dark Web offers.
When you access your banking information over the Internet using the HTTPS protocol (indicated by the https:// that starts the URL, and the green lock that most browsers display to allay your security fears), your information is secure. No one can see it in transit between your computer and the bank’s computer. But secure isn’t the same as anonymous.
Let’s back up just a bit and look at how the Internet works. Data moving between computers (even that streaming movie from Netflix) is divided into packets. And although it may appear that a packet sent from one computer to another computer goes directly from point A to point B, that’s not the case. The original Internet was built to survive an atomic war, which might disable significant parts of the network. So, each packet contains the address of its destination, and it’s passed between computers, each one, in turn, trying to move the packet closer to its final destination (or failing and letting the source of the packet know it was lost). Obviously, there’s a lot going on to make that happen. The point is that, typically, five to 10 intermediate computers (called routers) handle that packet in between A and B. Because the data inside the packet is secured by encryption, your bank balance can’t be read by those intermediaries, but each one knows where the packet started and where it’s going. So, no anonymity–anyone along the route could know you bank with Wells Fargo.
That means if I want to buy illegal drugs online (one of the most popular things one can do on the Dark Web), someone who can tap into those routers (say the FBI) can locate both me and the person selling the drugs. Not so good for either of us.
The same problem applies to governments trying to communicate with their intelligence agents. So the U.S. Naval Research Laboratory developed Tor, which stands for “The Onion Router.” As you might expect, Tor routes packets from one computer while hiding their source and destination from intermediaries, creating a “darknet.”
Tor works by installing software on your computer that knows how to communicate securely with the Tor network, a group of 4,500 computers (nodes) also running the Tor software. The Tor software randomly selects a group of Tor nodes through which your message will pass. You send your message to the first (entry) node. It’s then passed through the selected group of Tor nodes and leaves the Tor network via the last, or exit, node. The important point is that the only information exposed at each node is the address of the previous node and the address of the next node. The details of how this is accomplished are pretty technical, involving strong encryption and the mathematics of large prime numbers. Basically, it’s magic.
Here’s an analogy that might help. Each node in the Tor network provides you with a locking box marked on the outside with its node address. Only that node can unlock the box. Your message (with its destination address written on the outside) is placed in the box from the exit node, which, in turn, is placed in the box from the preceding node, until we get to the box from the entry node (which now contains a bunch of locked boxes–the analogy breaks down if you try and imagine how they all fit).
You give the locked box to the entry node. It opens that box with its key, sees the address of the next node, and gives the locked box to that node, which repeats the process until the exit node is reached. The exit node looks at the address on the outside of your message and delivers it there. As you can see, this is a little like peeling an onion; hence, The Onion Router.
Of course, the message itself should be encrypted with a key only the final destination can open, so it can’t be intercepted on the regular Internet between the exit node and the destination. But to the destination computer, your message appears to have originated at the Tor exit node, rather than your computer. Presto! You’re anonymous.
Note that using Tor doesn’t guarantee complete anonymity. For example, if you download an application that talks back to its owner via the regular Web, you’ve lost your anonymity. The same thing happens if you buy drugs with your credit card or have them sent to your home. It’s extremely difficult to be completely anonymous online, despite what you see on TV. And using Tor carries its own risks. The NSA is said to have an above-average interest in people who use Tor, since they must be hiding something.
More about the Dark Web next month!
