Anonymity and the Internet - Facts And Information
When communicating with others over the Internet, it is frequently preferred to not use any sort of identifiable handle (such as a "user name" or other arbitrary way of identifying who is speaking). The most popular worldwide example of this is within the Japanese forum 2channel. A common joke is that the poster 'Anonymous' is actually one person, which is obviously impossible given the number of posts attributed to that name. The forum prides itself on the total anonymity of those who post to the channel. The administrators of 2channel see the anonymous posting as a real benefit to those who post to the forum, because it is the argument, not the credibility of the author, that is being debated. This is in stark contrast to other Internet forums, such as Slashdot. In Slashdot-style forums, the ability to post anonymously is available, but other users of the forum tend to hold the content of the post in a lower regard than they would if a user with a registered username sent the same post. The Slashdot forum encourages this tendency by attributing posts like this to "Anonymous Coward," implying that the poster lacks the courage to stand by his or her statement.
When sending messages over the Internet, many people enjoy a sense of anonymity (or at least pseudonymity). Many popular systems, such as Usenet, e-mail, instant messaging, web forums, and P2P systems, foster this perception because there is often no obvious way for a casual user to connect other users with a "real world" identity.
On a technical level, all computers on the Internet use the Internet Protocol to speak to each other. Two-way communication at the protocol level requires that both parties know the IP address of the other. If communications are logged (for example, by the owner of a web-based bulletin board) or intercepted, the IP address of otherwise anonymous recipients may be discovered. Sometimes IP addresses are exposed directly as a feature of the communication system (often the case on Internet Relay Chat networks; also true for "anonymous" Wikipedia editors). Casual users often do not feel that knowledge of their IP address is enough for other participants to connect their online activities to their "real world" identities. Depending on their technical, physical, and legal access, a determined party (such a government prosecutor, or plaintiff in a lawsuit, or a determined stalker) may be able to do so, especially if they are assisted by the records of the Internet Service Provider which has assigned the IP address. Some IP addresses represent a specific computer. Others, due to proxies and Network Address Translation may represent any number of computers or users. It is usually easy to identify which ISP assigned the address, and this may reveal some identifying information about a person, such as geographic location or with the use of geo software the affiliation with a certain organization.
To achieve strong anonymity, intermediate services may be employed to thwart attempts at identification, even by governments. These attempt to use cryptography, passage through multiple legal jurisdictions, and various methods to thwart traffic analysis to achieve this. Examples include anonymous remailers, Anonymous P2P systems, and services of the Anonymizer company, among others.
More recent approaches in internet anonymity involve the use of Onion Routers such as Tor or Mix Cascades as in JAP. Onion routers and Mixes send information over encrypted protocols to several intermediate computers around the world in order to make identification more difficult.
This has been countered with advances in text analysis, in which the identity of a writer is determined by comparing the writing style of a piece to styles of pieces in which the author is known.