Onion routingOnion routing is a technique for anonymous communication over a computer network. In an onion network, messages are encapsulated in layers of encryption, analogous to the layers of an onion. The encrypted data is transmitted through a series of network nodes called "onion routers," each of which "peels" away a single layer, revealing the data's next destination. When the final layer is decrypted, the message arrives at its destination. The sender remains anonymous because each intermediary knows only the location of the immediately preceding and following nodes.
Internet censorship in ChinaChina censors both the publishing and viewing of online material. Many controversial events are censored from news coverage, preventing many Chinese citizens from knowing about the actions of their government, and severely restricting freedom of the press. China's censorship includes the complete blockage of various websites, apps, video games, inspiring the policy's nickname, the "Great Firewall of China", which blocks websites.
Internet censorship circumventionInternet censorship circumvention, also referred to as going over the wall () or scientific browsing () in China, is the use of various methods and tools to bypass internet censorship. Various techniques and methods are used to bypass Internet censorship, and have differing ease of use, speed, security, and risks. Some methods, such as the use of alternate DNS servers, evade blocking by using an alternate address or address lookup system to access the site.
Traffic analysisTraffic analysis is the process of intercepting and examining messages in order to deduce information from patterns in communication. It can be performed even when the messages are encrypted. In general, the greater the number of messages observed, the greater information be inferred. Traffic analysis can be performed in the context of military intelligence, counter-intelligence, or pattern-of-life analysis, and is also a concern in computer security. Traffic analysis tasks may be supported by dedicated computer software programs.
Tor (network)Tor, short for The Onion Router, is free and open-source software for enabling anonymous communication. It directs Internet traffic via a free, worldwide, volunteer overlay network that consists of more than seven thousand relays. Using Tor makes it more difficult to trace a user's Internet activity. Tor protects personal privacy by concealing a user's location and usage from anyone performing network surveillance or traffic analysis. It protects the user's freedom and ability to communicate confidentially through IP address anonymity using Tor exit nodes.
