Internet censorship is control or suppression of the publishing or accessing of information on the Internet. The legal issues are similar to offline censorship.

One difference is that national borders are more permeable online: residents of a country that bans certain information can find it on websites hosted outside the country. A government can try to prevent its citizens from viewing these even if it has no control over the websites themselves. Filtering can be based on a blacklist or be dynamic. In the case of a blacklist, that list is usually not published. The list may be produced manually or automatically.

Barring total control over Internet-connected computers, such as in North Korea, total censorship of information on the Internet is very difficult (or impossible) to achieve due to the underlying distributed technology of the Internet. Pseudonymity and data havens (such as Freenet) allow unconditional free speech, as the technology guarantees that material cannot be removed and the author of any information is impossible to link to a physical identity or organization.

In some cases, Internet censorship may involve deceit. In such cases the censoring authority may block content while leading the public to believe that censorship has not been applied. This may be done by having the ISP provide a fake "Not Found" error message upon the request of an Internet page that is actually found but blocked (see 404 error for details).

In November 2007, "Father of the Internet" Vint Cerf stated that he sees Government-led control of the Internet failing due to private ownership. Many internet experts use the term "splinternet" to describe some of the effects of national firewalls.

Methods

Jo Glanville, editor of Index on Censorship observes that "censorship, for the first time in its history, is now a commercial enterprise".^[1]

Technical censorship

Some commonly used methods for (partial) censoring content are:^[2]

• IP blocking. Access to a certain IP address is denied. If the target Web site is hosted in a shared hosting server, all websites on the same server will be blocked. This affects IP-based protocols such as HTTP, FTP and POP. A typical circumvention method is to find proxies that have access to the target websites, but proxies may be jammed or blocked, and some Web sites, such as Wikipedia (when editing), also block proxies. Some large websites like Google have allocated additional IP addresses to circumvent the block, but later the block was extended to cover the new IPs.
• DNS filtering and redirection. Don't resolve domain names, or return incorrect IP addresses. This affects all IP-based protocols such as HTTP, FTP and POP. A typical circumvention method is to find a domain name server that resolves domain names correctly, but domain name servers are subject to blockage as well, especially IP blocking. Another workaround is to bypass DNS if the IP address is obtainable from other sources and is not blocked. Examples are modifying the Hosts file or typing the IP address instead of the domain name in a Web browser.
• Uniform Resource Locator (URL) filtering. Scan the requested URL string for target keywords regardless of the domain name specified in the URL. This affects the HTTP protocol. Typical circumvention methods are to use escaped characters in the URL, or to use encrypted protocols such as VPN and TLS/SSL.^[3]
• Packet filtering. Terminate TCP packet transmissions when a certain number of controversial keywords are detected. This affects all TCP-based protocols such as HTTP, FTP and POP, but Search engine results pages are more likely to be censored. Typical circumvention methods are to use encrypted connections - such as VPN and TLS/SSL - to escape the HTML content, or by reducing the TCP/IP stack's MTU/MSS to reduce the amount of text contained in a given packet.
• Connection reset. If a previous TCP connection is blocked by the filter, future connection attempts from both sides will also be blocked for up to 30 minutes. Depending on the location of the block, other users or websites may also be blocked if the communication is routed to the location of the block. A circumvention method is to ignore the reset packet sent by the firewall.^[4]
• Reverse surveillance. Computers accessing certain websites including Google are automatically exposed to reverse scanning from the ISP in an apparent attempt to extract further information from the "offending" system.^{[citation needed]}

One of the most popular filtering software programmes is SmartFilter, owned by Secure Computing in California, which has recently been bought by McAfee. SmartFilter has been used by Tunisia, Saudi Arabia and Sudan, as well as in the US and the UK.^[1]

Full block

A technically simpler method of internet censorship is to completely cut off all routers, either by software or by hardware (turning off machines, pulling out cables). This appears to have been the case on 27/28 January 2011 during the 2011 Egyptian protests, in what has been widely described as an "unprecedented" internet block.^[5][6] About 3500 Border Gateway Protocol (BGP) routes to Egyptian networks were shut down from about 22:10 to 22:35 UTC 27 January.^[5] This full block was implemented without cutting off major intercontinental fibre-optic links, with Renesys stating on 27 January, "Critical European-Asian fiber-optic routes through Egypt appear to be unaffected for now."^[5]

"By-catch"

See also Internet forum#Word censor and Anti-spam techniques#Detecting spam.

Automatic censorship sometimes stops matter which it was not intended to stop. An example is that automatic censorship against sexual words in matter for children, set to block the word "cunt", has been known to block the Lincolnshire (UK) placename Scunthorpe.

Circumvention

There are a number of resources that allow users to bypass the technical aspects of Internet censorship. Each solution has differing ease of use, speed, and security from other options. Most, however, rely on gaining access to an internet connection that is not subject to filtering, often in a different jurisdiction not subject to the same censorship laws. This is an inherent problem in internet censorship in that so long as there is one publicly accessible system in the world without censorship, it will still be possible to have access to censored material.

Proxy websites

Proxy websites are often the simplest and fastest way to access banned websites in censored nations. Such websites work by being themselves un-banned but capable of displaying banned material within them. This is usually accomplished by entering a URL address which the proxy website will fetch and display. They recommend using the https protocol since it is encrypted and harder to block.

Java Anon Proxy

Java Anon Proxy is primarily a strong, free and open source anonymizer software available for all operating systems. As of 2004^[update], it also includes a blocking resistance functionality that allows users to circumvent the blocking of the underlying anonymity service AN.ON by accessing it via other users of the software (forwarding client).^{[citation needed]}

The addresses of JAP users that provide a forwarding server can be retrieved by getting contact to AN.ON's InfoService network, either automatically or, if this network is blocked, too, by writing an e-mail to one of these InfoServices. The JAP software automatically decrypts the answer after the user completes a CAPTCHA. The developers are currently^{[citation needed]} planning to integrate additional and even stronger blocking resistance functions.

Virtual Private Networks (VPNs)

Using Virtual Private Networks, a user who experiences internet censorship can create a secure connection to a more permissive country, and browse the internet as if they were situated in that country. Some services are offered for a monthly fee, others are ad-supported.

Psiphon

Psiphon software allows users in nations with censored Internet such as China to access banned websites like Wikipedia. The service requires that the software be installed on a computer with uncensored access to the Internet so that the computer can act as a proxy for users in censored environments.^[7]

Freenet

Freenet is a decentralized, censorship-resistant distributed data store. Unlike many other P2P applications, Freenet does not have a single application which provides all functionality.

I2P

I2P is open source software that can be used for anonymous surfing, chatting, blogging and file transfers, among other things.

JonDos

JonDos is based on open source software and provides secure and fast anonymizing networking.

Tor

Tor is a free software implementation that allows users to bypass Internet censorship while granting strong anonymity.

Sneakernets

Sneakernet is a term used to describe the transfer of electronic information, especially computer files, by physically carrying data on storage media from one place to another. A sneakernet can move data regardless of network restrictions simply by not using the network at all.^[8]

Around the world

In 2006, Reporters without Borders (Reporters sans frontières, RSF, a Paris-based international non-governmental organization that advocates freedom of the press) published a list of the 13 "enemies of the Internet":^[9] The organization classifies a country as an enemy of the internet because "all of these countries mark themselves out not just for their capacity to censor news and information online but also for their almost systematic repression of Internet users."^[10] The list is updated annually and includes 12 countries in 2009 and 2010.^[11]

On the 12th, March 2011, Reporters Without Borders published the updated list of the Internet Enemies:

•  Burma
•  China
•  Cuba
•  Tunisia
•  Iran
•  North Korea
•  Saudi Arabia
•  Syria
•  Turkmenistan
•  Uzbekistan
•  Vietnam
•  Egypt

During the Arab Spring of 2011 mediajihad (or media struggle) was extensive.^[12]

Portal censorship

Major portals occasionally exclude web sites that they would ordinarily include. This renders a site invisible to people who do not know where to find it. When a major portal does this, it has a similar effect as censorship. Sometimes this exclusion is done to satisfy a legal or other requirement, other times it is purely at the discretion of the portal.

Examples

• Google.de and Google.fr remove Neo-Nazi and other listings in compliance with German and French law.^[13]

Major web portal official statements on site removal

• Google:^[14] "Google may temporarily or permanently remove sites from its index and search results if it believes it is obligated to do so by law, if the sites do not meet Google's quality guidelines, or for other reasons, such as if the sites detract from users' ability to locate relevant information."
• Yahoo!:^[15] Yahoo!'s terms of service state that they reserve the right to "pre-screen, refuse or remove" any content that they feel violates the terms of service or deem distasteful; however, removing information is never obligatory. Yahoo! also does not reserve the right to pre-screen any information.

Commonly targeted websites

• Pornographic and fetishism websites.
• Pedophile-related and other websites considered highly objectionable (see also CIRCAMP)
• Media sharing website (e.g. Flickr and YouTube^[16])
• Social networks (e.g. Facebook, MySpace and Twitter)
• Wikipedia
• Wikileaks^[17]
• Political blogs^[18]
• Nazi and similar websites — particularly in France and Germany^[19]
• Religious websites
• Filesharing and P2P-related websites
• Google - particularly in mainland China and Cuba^[20]
• Censorship-circumvention websites
• Foreign websites
• 4chan

See also

Template:Wikipedia-Books

• Censorship by Google
• Computer surveillance
• Content-control software
• Criticism of Wikipedia, Censorship
• Cyber-dissident
• Electronic Frontier Foundation
• For the children (politics)
• Geolocation
• Internet Governance Forum (IGF)
• Internet police - flooding rather than censoring
• Irrepressible.info
• OpenNet Initiative
• Political repression of cyber-dissidents
• Proxy list
• Scieno Sitter
• Scientology versus the Internet
• Sociology of the Internet
• Splinternet

References

External links

• Wikia Censorship at Wikia
• Internet censorship wiki at cship.org
• Index on Censorship