Tor (The Onion Router): Free software for enabling anonymous communication on the internet.
What is Tor (The Onion Router)?
Tor is free and open-source software designed to enable anonymous communication over the Internet. It directs Internet traffic through a volunteer network consisting of thousands of relays to conceal a user’s location and usage from anyone conducting network surveillance or traffic analysis. The name “Onion Router” comes from the idea of layering, much like an onion, where each relay peels back one layer of encryption to reveal the next relay destination.
How Does Tor Work?
- Multi-Layered Encryption: When data is sent over the Tor network, it’s encrypted in multiple layers.
- Relay Network: This encrypted data then bounces through a series of relays, each peeling away one layer of encryption to reveal the next destination.
- Exit Node: The final relay, known as the exit node, sends the data to its final destination. Importantly, even the exit node can’t see both the source and destination of the data.
- Entry Guard: To prevent single points of failure or compromise, Tor uses “entry guards,” or trusted first-relay points that a user’s Tor client will stick to for a longer period.
Why Use Tor?
- Anonymity: It’s an effective way to browse the Internet anonymously, shielding users from tracking and surveillance.
- Privacy: Ideal for those who require a high degree of privacy for personal or professional reasons.
- Access to the Deep Web: Tor enables access to ‘.onion’ websites that are part of the deep web, hidden from traditional search engines.
- Censorship Circumvention: Users can bypass Internet censorship and firewalls to access websites otherwise blocked in their region.
Risks and Downsides
- Slow Speeds: Due to its multi-hop architecture, browsing can be slow.
- Illegal Activity: The network can be used for nefarious activities, leading some to view Tor with suspicion.
- Potential Monitoring: Though rare, compromised exit nodes can potentially monitor or alter outgoing traffic.
Application in Various Fields
- Journalism: Reporters use Tor to communicate more safely.
- Activism: Activists use Tor to protect their identity while spreading information.
- Law Enforcement: Agencies use Tor for reconnaissance and to visit websites without leaving government IP addresses in web logs.