China 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. Methods used to block websites and pages include DNS spoofing, blocking access to IP addresses, analyzing and filtering URLs, packet inspection, and resetting connections.
The Great Firewall is the combination of legislative actions and technologies enforced by the People's Republic of China to regulate the Internet domestically. Its role in internet censorship in China is to block access to selected foreign websites and to slow down cross-border internet traffic. The Great Firewall operates by checking transmission control protocol (TCP) packets for keywords or sensitive words. If the keywords or sensitive words appear in the TCP packets, access will be closed. If one link is closed, more links from the same machine will be blocked by the Great Firewall. The effect includes: limiting access to foreign information sources, blocking foreign internet tools and mobile apps, and requiring foreign companies to adapt to domestic regulations.
The OpenNet Initiative (ONI) was a joint project whose goal was to monitor and report on internet filtering and surveillance practices by nations. Started in 2002, the project employed a number of technical means, as well as an international network of investigators, to determine the extent and nature of government-run internet filtering programs. Participating academic institutions included the Citizen Lab at the Munk Centre for International Studies, University of Toronto; Berkman Center for Internet & Society at Harvard Law School; the Oxford Internet Institute (OII) at University of Oxford; and, The SecDev Group, which took over from the Advanced Network Research Group at the Cambridge Security Programme, University of Cambridge.
Google China is a subsidiary of Google. Once a popular search engine, most services offered by Google China were blocked by the Great Firewall in the People's Republic of China. In 2010, searching via all Google search sites, including Google Mobile, was moved from mainland China to Hong Kong.
Psiphon is a free and open-source Internet censorship circumvention tool that uses a combination of secure communication and obfuscation technologies, such as a VPN, SSH, and a Web proxy. Psiphon is a centrally managed and geographically diverse network of thousands of proxy servers, using a performance-oriented, single- and multi-hop routing architecture.
Censorship in the People's Republic of China is mandated by the PRC's ruling party, the Chinese Communist Party (CCP). It is one of the strictest censorship regimes in the world. The government censors content for mainly political reasons, such as curtailing political opposition, and censoring events unfavorable to the CCP, such as the 1989 Tiananmen Square protests and massacre, pro-democracy movements in China, the persecution of Uyghurs in China, human rights in Tibet, Falun Gong, pro-democracy protests in Hong Kong, and aspects of the COVID-19 pandemic. Since Xi Jinping became the general secretary of the Chinese Communist Party in 2012, censorship has been "significantly stepped up".
Internet censorship is the legal control or suppression of what can be accessed, published, or viewed on the Internet. Censorship is most often applied to specific internet domains but exceptionally may extend to all Internet resources located outside the jurisdiction of the censoring state. Internet censorship may also put restrictions on what information can be made internet accessible. Organizations providing internet access – such as schools and libraries – may choose to preclude access to material that they consider undesirable, offensive, age-inappropriate or even illegal, and regard this as ethical behavior rather than censorship. Individuals and organizations may engage in self-censorship of material they publish, for moral, religious, or business reasons, to conform to societal norms, political views, due to intimidation, or out of fear of legal or other consequences.
Server Name Indication (SNI) is an extension to the Transport Layer Security (TLS) computer networking protocol by which a client indicates which hostname it is attempting to connect to at the start of the handshaking process. The extension allows a server to present one of multiple possible certificates on the same IP address and TCP port number and hence allows multiple secure (HTTPS) websites to be served by the same IP address without requiring all those sites to use the same certificate. It is the conceptual equivalent to HTTP/1.1 name-based virtual hosting, but for HTTPS. This also allows a proxy to forward client traffic to the right server during TLS/SSL handshake. The desired hostname is not encrypted in the original SNI extension, so an eavesdropper can see which site is being requested. The SNI extension was specified in 2003 in RFC 3546
UC Browser is a web browser developed by mobile internet company UCWeb, a subsidiary of the Alibaba Group. It was the most popular mobile browser in India, Indonesia, and Mali, as well as the second most popular one in China as of 2017. Its world-wide browser share as of May 2022 is 0.86% overall according to StatCounter.
An Internet outage or Internet blackout or Internet shutdown is the complete or partial failure of the internet services. It can occur due to censorship, cyberattacks, disasters, police or security services actions or errors.
Internet 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.
Lantern is a free internet censorship circumvention tool that operates in some of the most extreme censorship environments, such as China, Iran, and Russia. It uses wide variety of protocols and techniques that obfuscate network traffic and/or co-mingle traffic with protocols censors are reluctant to block. It also uses domain fronting. It is not an anonymity tool like Tor.
Morgan Marquis-Boire is a New Zealand-born hacker, journalist, and security researcher. Marquis-Boire previously served as an advisor to the Freedom of the Press Foundation. He was a Special Advisor to the Electronic Frontier Foundation (EFF) and advisor to the United Nations Interregional Crime and Justice Research Institute. He was the Director of Security at First Look Media and a contributing writer at The Intercept. He has been profiled by Wired, CNN, Süddeutsche Zeitung, and Tages Anzeiger. He was one of Wired Italy 's Top 50 people of 2014. In March 2015 he was named a Young Global Leader.
GitHub has been the target of censorship from governments using methods ranging from local Internet service provider blocks, intermediary blocking using methods such as DNS hijacking and man-in-the-middle attacks, and denial-of-service attacks on GitHub's servers from countries including China, India, Iraq, Russia, and Turkey. In all of these cases, GitHub has been eventually unblocked after backlash from users and technology businesses or compliance from GitHub.
GreatFire (GreatFire.org) is a website that monitors the status of websites censored by the Great Firewall of China and helps Chinese Internet users circumvent the censorship and blockage of websites in China. The site was first launched in 2011 by an anonymous trio. GreatFire is funded by sources inside and outside China, including the US-government-backed Open Technology Fund.
The Cyberspace Administration of China is the national internet regulator and censor of the People's Republic of China.
Shadowsocks is a free and open-source encryption protocol project, widely used in China to circumvent Internet censorship. It was created in 2012 by a Chinese programmer named "clowwindy", and multiple implementations of the protocol have been made available since. Shadowsocks is not a proxy on its own, but (typically) is the client software to help connect to a third-party SOCKS5 proxy, which is similar to a Secure Shell (SSH) tunnel. Once connected, internet traffic can then be directed through the proxy. Unlike an SSH tunnel, shadowsocks can also proxy User Datagram Protocol (UDP) traffic.
Domain fronting is a technique for Internet censorship circumvention that uses different domain names in different communication layers of an HTTPS connection to discreetly connect to a different target domain than is discernable to third parties monitoring the requests and connections.
In 2015, the government of Kazakhstan created a root certificate which could have enabled a man-in-the-middle attack on HTTPS traffic from Internet users in Kazakhstan. The government described it as a "national security certificate". If installed on users' devices, the certificate would have allowed the Kazakh government to intercept, decrypt, and re-encrypt any traffic passing through systems it controlled.
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