Discovering Tor Browser: The Digital Fortress for Online Privacy

Raffaela Crisci : 15 November 2025 16:12

Tor Browser (short for The Onion Router) is a free, open-source web browser designed specifically to protect users’ online privacy. Using a network of servers distributed around the world, Tor allows users to browse the internet anonymously, hiding their identity and geographic location, and making it difficult to track their online activity.

Tor has its roots in the early 2000s, but the onion routing concept on which it is based dates back to the 1990s, developed at the U.S. Naval Research Laboratory.

Initially created to protect the communications of undercover agents, the project was later declassified and made public, spawning a community of developers and users who helped make it the tool we know today. In 2002, Roger Dingledine and Nick Mathewson, along with Paul Syverson, launched the first public version of the Tor network.

How does Tor work?

The Tor Browser works by routing your internet traffic through a centralized network of volunteer-run servers around the world. These servers, called “nodes,” encrypt the traffic so that neither the site you’re visiting nor third parties can easily identify the source of the traffic.

1. Onion Routing (Onion Routing) :
   • Layered Structure : Onion routing is the heart of Tor technology. When a user sends a request through Tor, the data is encapsulated in multiple layers of encryption, like an onion. Each node in the Tor network removes a single layer of encryption before forwarding the message to the next node, revealing only the next destination. No single node knows the origin and final destination of the data, making it difficult to trace its path.
2. Nodes and Circuits :
   • Ingress, Intermediary, and Egress Nodes : Traffic passes through three main nodes: an ingress node, an intermediary node, and an egress node. The ingress node knows the user’s IP address, but not the traffic content or final destination. The egress node knows the final destination, but not the original user’s IP address. Intermediaries simply route the traffic.
   • Circuits : Each Tor session uses a circuit, which is a path through three randomly selected nodes. These circuits are periodically changed to increase security.
3. Encryption :
   • AES and RSA : Tor uses a combination of symmetric (AES) and asymmetric (RSA) encryption to secure data as it passes through the network. Each node in the circuit has a unique AES key that decrypts one layer of the encrypted message, while RSA keys secure the session.
   • Perfect Forward Secrecy : Tor implements Perfect Forward Secrecy, which means that each session uses temporary cryptographic keys that are destroyed after use, ensuring that even if one key were compromised, it would not compromise past or future sessions.

Access to the Dark Web : Tor is also known for allowing access to hidden websites, known as “.onion” services, which are inaccessible through standard browsers and search engines. These sites can be used for legitimate purposes, such as protecting communications in oppressive regimes, but also for illicit activities.

Over the years, the Tor Project has faced several challenges, including government censorship attempts and network attacks designed to deanonymize users. However, thanks to the support of the open-source community and continuous innovation, Tor has remained a key pillar of online privacy.

Criticisms, limitations, social and political impact

Tor is not without its critics and limitations. Accessibility to the Dark Web has led to a series of ethical and legal implications. On the one hand, Tor has been a crucial tool for investigative journalists, activists, and dissidents operating in repressive environments, allowing them to communicate securely and anonymously. On the other hand, Tor’s anonymous nature has made it a haven for illegal activities, such as drug trafficking, tax evasion, and child pornography. This duality has led to growing scrutiny from law enforcement and governments, who often view Tor as a tool used exclusively by criminals.

Tor isn’t a panacea. It can’t protect against malware or local man-in-the-middle attacks. Furthermore, connection speeds can be limited, especially for bandwidth-intensive activities.

Conclusions

The Tor Browser remains one of the most powerful tools for protecting online privacy. Its complex onion routing architecture, combined with robust encryption, makes it an essential tool for anyone wishing to browse anonymously. However, like any technology, it is not foolproof and requires careful and informed use to maximize security.

The future of Tor Browser will continue to evolve as new threats and challenges emerge, but its importance as a bastion of online freedom and privacy is unquestionable.

Raffaela Crisci
Member of the Dark Lab group. Computer Engineer graduated with honors from the University of Sannio, with specialization in Cyber Security. Expert in Cyber Threat Intelligence with experience in a leading multinational company. Strong discipline and organizational skills developed through sports

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