An anonymizer or an anonymous proxy is a tool that attempts to make activity on the Internet untraceable. It is a proxy server computer that acts as an intermediary and privacy shield between a client computer and the rest of the Internet. It accesses the Internet on the user's behalf, protecting personal information by hiding the client computer's identifying information.
There are many purposes for using anonymizers. Anonymizers help minimize risk. They can be used to prevent identity theft, or to protect search histories from public disclosure.
However, anonymizers can also be used by individuals wishing to avoid the consequences of engaging in criminal, disruptive, or socially unacceptable behaviour online. For example much of the child pornography distributed through the internet is accessed through anonymizers. Also, they are used to bypass web technologies that limit online content access to a certain number of minutes or quantity of data.
Some countries, especially dictatorships or Islamic countries, fail to serve the rights of minority groups, or oppress any opposition to their government. These countries apply heavy censorship on the internet, sometimes with the death penalty. Anonymizers can help in allowing free access to all of the internet content, but cannot help against persecution for accessing the Anonymizer website itself. Furthermore, as information itself about Anonymizer websites are banned in these countries, users are wary that they may be falling into a government set trap.
Libertarian and other movements concerned with the growing Orwellian grip of governments in free societies advocate using Anonymizer services in order to avoid government or other organized tracking.
Anonymizers are also used by people who wish to receive objective information with the growing Target marketing on the internet and targeted information. For example, large news outlets such as CNN target the viewers according to region and give different information to different populations. Websites such as YouTube obtain information about the last videos viewed on a computer, and propose "recommended" video's accordingly, and most of the online targeted marketing is done by showing advertisements according to that region. Anonymizers are used for avoiding this kind of targeting and getting a more objective view of information.
Use of anonymizersEdit
Protocol specific anonymizersEdit
Sometimes anonymizers are implemented to work only with one particular protocol. The advantage is that no extra software is needed. The operation occurs in this manner: A connection is made by the user to the anonymizer. Commands to the anonymizer are included inside a typical message. The anonymizer then makes a connection to the resource specified by the in-bound command and relays the message with the command stripped out.
Protocol independent anonymizersEdit
In this case either the desired application must support the tunneling protocol, or a piece of software must be installed to force all connections through the tunnel. Web browsers, FTP and IRC clients often support SOCKS for example, unlike telnet.
Use of multiple relaysEdit
One example of "daisy-chained" anonymizing proxies is the "Tor network". Tor does not encrypt your traffic from end to end, rather it builds up a series of encrypted connections through the relays in the Tor network. An additional layer of encryption should be used with Tor if end-to-end encryption is required. See risks of using anonymous proxy servers.
Another example is I2P - the Anonymous Network. It works similarly to Tor, yet with some crucial differences: I2P is an internal network. It is totally decentralized and does not rely on central lists servers and unlike Tor it uses no bidrectional tunnels, which makes timing attacks far more difficult, and it is end-to-end encrypted. As you never know if a given mix logs all connections or not, the only way to be really sure there is no logging is to run your own anonymizing mix node and blend your traffic with those of other users, who in turn need not trust you, as they blend their traffic with yours and other users' traffic in their own mix nodes. This is the philosophy behind i2p - each nodes routes traffic for others and blends its own traffic in, whereas one's own traffic will be relayed by other peers through so-called tunnels made-up of various other peers. The network is highly dynamic and totally decentralized. It also takes care of other nodes learning about your node existing, for without peers using your node, there would be no traffic to blend yours with. As all traffic always stay within the i2p network, a routing user's i2p will never show on public websites' logs.
Another example of multiple relays is sending an e-mail to an anonymizing remailer, which relays it to another remailer, which eventually relays it to its destination.
- "How Anonymizers Work". The Living Internet. http://www.livinginternet.com/i/is_anon_work.htm. Retrieved 2007-08-03.
- "List of the 13 Internet enemies". Reporters Without Borders. http://www.rsf.org/article.php3?id_article=19603. Retrieved January 9, 2008.
- Anonymizer to provide censor-free internet to China (Anonymizer.com website)
- US FBI uses 'Anonymizer trap' to catch online pedofiles (Security Focus website)
- "How to use Bitcoin, the most imnportant creation in history" - Article on the Libertarian News website
- About targeted advertising on an anonymizer (FastCompany Anonymizer website) - an article describing the typical targeted advertising avoidance by most anonymizer services, while this one enables continued online targeted marketing
- The hack of the year