An anonymizer or an anonymous proxy is a tool that attempts to make activity on the

Internet The Internet (or internet) is the global system of interconnected computer networks that uses the Internet protocol suite (TCP/IP) to communicate between networks and devices. It is a '' network of networks'' that consists of private, pub ...

untraceable. It is a

proxy server In computer networking, a proxy server is a server application that acts as an intermediary between a client requesting a resource and the server providing that resource. Instead of connecting directly to a server that can fulfill a request ...

computer that acts as an intermediary and

privacy Privacy (, ) is the ability of an individual or group to seclude themselves or information about themselves, and thereby express themselves selectively. The domain of privacy partially overlaps with security, which can include the concepts of a ...

shield between a client computer and the rest of the

. It accesses the Internet on the user's behalf, protecting personal information of the user by hiding the client computer's identifying information. Anonymous proxy is the opposite of

transparent proxy In computer networking, a proxy server is a server application that acts as an intermediary between a client requesting a resource and the server providing that resource. Instead of connecting directly to a server that can fulfill a request ...

, which sends user information in the connection request header.

Purposes

There are many reasons for using anonymizers, such as minimizing risk, prevention of

identity theft Identity theft occurs when someone uses another person's personal identifying information, like their name, identifying number, or credit card number, without their permission, to commit fraud or other crimes. The term ''identity theft'' was co ...

, or protecting search histories from public disclosure. Some countries apply heavy censorship on the internet. Anonymizers can help to allow free access to all of the internet content, but they cannot help against persecution for accessing the anonymizer website itself. Furthermore, as information itself about anonymizer websites are banned in those countries, users are wary that they may be falling into a government-set trap. 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 CNN (Cable News Network) is a multinational cable news channel headquartered in Atlanta, Georgia, U.S. Founded in 1980 by American media proprietor Ted Turner and Reese Schonfeld as a 24-hour cable news channel, and presently owned by ...

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 they propose "recommended" videos accordingly, and most of the online targeted marketing is done by showing advertisements according to that region. Anonymizers are used for avoiding that kind of targeting and getting a more objective view of information. For building a reliable anonymous system, anonymous proxy signatures are helpful. It can be used in anonymous voting or other authentication processes that value anonymity.

Types of anonymizers

Protocol-specific anonymizers

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 inbound command and relays the message with the command stripped out. An example of a protocol-specific anonymizer is an

anonymous remailer An anonymous remailer is a server that receives messages with embedded instructions on where to send them next, and that forwards them without revealing where they originally came from. There are cypherpunk anonymous remailers, mixmaster anonym ...

for e-mail. Also of note are web proxies, and

bouncers A bouncer (also known as a doorman or door supervisor) is a type of security guard, employed at venues such as bars, nightclubs, cabaret clubs, stripclubs, casinos, hotels, billiard halls, restaurants, sporting events, schools, concerts, ...

for

FTP The File Transfer Protocol (FTP) is a standard communication protocol used for the transfer of computer files from a server to a client on a computer network. FTP is built on a client–server model architecture using separate control and data ...

and

IRC Internet Relay Chat (IRC) is a text-based chat system for instant messaging. IRC is designed for group communication in discussion forums, called '' channels'', but also allows one-on-one communication via private messages as well as chat an ...

. Potentially anonymity integrated with RFID tags could pose as an option.

Protocol-independent anonymizers

Protocol independence can be achieved by creating a

tunnel A tunnel is an underground passageway, dug through surrounding soil, earth or rock, and enclosed except for the entrance and exit, commonly at each end. A pipeline is not a tunnel, though some recent tunnels have used immersed tube cons ...

to an anonymizer. There are various technologies to do so. Protocols used by anonymizer services may include

SOCKS A sock is a piece of clothing worn on the feet and often covering the ankle or some part of the calf. Some types of shoes or boots are typically worn over socks. In ancient times, socks were made from leather or matted animal hair. In the late ...

PPTP The Point-to-Point Tunneling Protocol (PPTP) is an obsolete method for implementing virtual private networks. PPTP has many well known security issues. PPTP uses a TCP control channel and a Generic Routing Encapsulation tunnel to encapsulate PP ...

, or

OpenVPN OpenVPN is a virtual private network (VPN) system that implements techniques to create secure point-to-point or site-to-site connections in routed or bridged configurations and remote access facilities. It implements both client and server appl ...

. 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 Telnet is an application protocol used on the Internet or local area network to provide a bidirectional interactive text-oriented communication facility using a virtual terminal connection. User data is interspersed in-band with Telnet control i ...

Use of multiple relays

Proxies can be daisy chained. Chaining anonymous proxies can make

traffic analysis Traffic 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 ...

far more complex and costly by requiring the eavesdropper to be able to monitor different parts of the Internet. An anonymizing remailer can use this concept by relaying a message to another remailer, and eventually to its destination. Even stronger anonymity can be gained by using

Tor Tor, TOR or ToR may refer to: Places * Tor, Pallars, a village in Spain * Tor, former name of Sloviansk, Ukraine, a city * Mount Tor, Tasmania, Australia, an extinct volcano * Tor Bay, Devon, England * Tor River, Western New Guinea, Indonesia Sc ...

. Tor is not merely a proxy chain, but an

onion router Onion routing is a technique for anonymous communication over a computer network. In an onion network, messages are encapsulated in layers of encryption, analogous to layers of an onion. The encrypted data is transmitted through a series of net ...

, which means that routing information (as well as message content) is

encrypted In cryptography, encryption is the process of encoding information. This process converts the original representation of the information, known as plaintext, into an alternative form known as ciphertext. Ideally, only authorized parties can deci ...

in such a way as to prevent linking the origin and destination. Like all anonymity networks, Tor cannot end-to-end encrypt messages destined for the public internet; it must be arranged between the sender and recipient. Tor's onion service protocol does, however, provide

end-to-end encryption End-to-end encryption (E2EE) is a system of communication where only the communicating users can read the messages. In principle, it prevents potential eavesdroppers – including telecommunications service providers, telecom providers, Internet ...

, along with the ability to anonymize servers, making them more censorship-resistant. Another anonymity network is the Invisible Internet Project (I2P). Unlike Tor, I2P is a fully internal network. The philosophy behind I2P is that each node 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. 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. These other users do not need to trust you, as they blend their traffic with yours and other users' traffic in their own mix nodes. The network is highly dynamic and fully 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 stays within the I2P network, a routing user's I2P can remain end-to-end encrypted and will never show on public websites' logs.

Examples

Examples of anonymizer websites include Anonymouse, Anonymiz.com, Anonymize,

Anonymizer 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 acce ...

, IDZap, Ultimate Anonymity, The Cloak and GhostSurf Platinum.

References

{{Reflist Anonymity