Module # 3

What is Tor ?

Tor stands for The Onion Router. It is a free software and network that helps people use the internet more privately and anonymously.When you use normal internet, your data usually goes directly from your device to the website. Your IP address (your internet identity) can be seen by websites or internet providers.But Tor works differently.Tor sends your internet traffic through many different computers (called nodes or relays) around the world. Each relay only knows the previous and next step, not the whole path.Because the data passes through many layers of encryption, it is called “Onion Routing” (like layers of an onion).

Platforms Where Tor is Available

Tor can be used on different operating systems and devices.

1. Windows

Tor Browser is available for Windows computers.

2. Linux

Works on most Linux distributions like Ubuntu, Kali Linux, Debian, Arch etc.

3. macOS

Tor Browser is also available for Apple Mac computers.

4. Android

Android users can use Tor Browser from the Play Store or official website.

5. iOS (iPhone / iPad)

There is no official Tor Browser, but apps like Onion Browser allow Tor access.

What is an Onion Website?

An Onion website is a special type of website that works only on the Tor network.Normal websites use domains like:

But Onion websites use a different domain that ends with:

Example of an onion address:

These addresses look long and random because they are automatically generated for security.

Onion Routing Explained

Onion Routing is the technology used by Tor to protect a user's privacy on the internet. It works by sending internet data through several different computers in the Tor network instead of sending it directly to a website. Before the data leaves the user’s device, it is wrapped in multiple layers of encryption, just like the layers of an onion. Because of these layers, the system is called onion routing. As the data travels through the Tor network, each relay (computer) removes only one layer of Encryption and then passes the data to the next relay. This process continues until the data reaches its final destination.The important idea behind onion routing is that no single computer in the network knows the complete path of the data. The first node only knows the user’s device but not the final website, while the last node knows the website but not the real user. Because the information is divided in this way, it becomes very difficult for anyone to trace the original user or track their online activity. This method helps provide a higher level of privacy and anonymity when browsing the internet using Tor.

Tor Encryption Basics

Encryption in Tor is the main technology that protects a user's privacy. Encryption means converting normal readable data into a coded form so that other people cannot understand it. When someone uses Tor, their internet traffic is encrypted multiple times before it leaves their device. This is called layered encryption, and it works like the layers of an onion. The Tor browser first selects several relays (servers) in the Tor network and then wraps the data in different layers of encryption for each relay. As the data travels through the network, every relay removes only one layer of encryption and forwards the data to the next relay. Because each relay only removes its own layer, no relay can see the full information about both the sender and the final destination. This system helps make tracking users much harder and improves anonymity on the internet.

Another important part of Tor encryption is that every connection uses temporary encryption keys that change regularly. These keys are used to protect the communication between the user and each relay in the network. Even if someone tries to monitor the traffic, they will only see encrypted data that is extremely difficult to decode. This method ensures that the user's identity, location, and browsing activity remain protected while the data travels across different relays in the Tor network.

Hidden Services (Tor)

Hidden Services are special services on the Tor that allow websites or servers to stay anonymous while still being accessible to users on the Tor network. These services are often called Onion Services because they use addresses that end with “.onion”. Unlike normal websites, hidden services do not reveal the real location or IP address of the server that hosts the website. This means both the visitor and the website owner can remain anonymous.When a user wants to visit a hidden service, the connection does not go directly to the server. Instead, Tor creates a secure connection through several relays inside the Tor network. The hidden service also connects to the network using Tor and publishes special information that allows users to find it. Then Tor creates a meeting point inside the network, called a rendezvous point, where the user and the hidden service connect without knowing each other’s real identities. Because of this system, the real IP address of both sides stays hidden.Hidden services are used for different purposes such as private communication, secure websites, and services that require strong privacy protection. They allow people to host websites or platforms without exposing their real location on the internet.