overview.html (bcef2f514) - tor-webwml.git

bcef2f5144d86e99fd2c4c10ecff757b17a20d91

first cut of new website Roger Dingledine authored 19 years ago	`1) <!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.1//EN" "http://www.w3.org/TR/xhtml11/DTD/xhtml11.dtd"> 2) 3) <html xmlns="http://www.w3.org/1999/xhtml" xml:lang="en"> 4) <head> 5) <title>Tor: Overview</title>`
clean up my meta and br tags Roger Dingledine authored 19 years ago	`6) <meta name="Author" content="Roger Dingledine" />`
first cut of new website Roger Dingledine authored 19 years ago	`7) <meta http-equiv="content-type" content="text/html; charset=ISO-8859-1" /> 8) <link rel="stylesheet" type="text/css" href="default.css" />`
list the favicon on every page Roger Dingledine authored 19 years ago	`9) <link rel="shortcut icon" type="image/x-icon" href="/favicon.ico" />`
first cut of new website Roger Dingledine authored 19 years ago	`10) </head> 11) 12) <body> 13) <div class="menu" id="side"> 14) <!-- <img id="logo" src="tor.jpg" alt="cute tor gate" /> -->`
clean up my meta and br tags Roger Dingledine authored 19 years ago	`15) <a href="index.html">Home</a> <br />`
website patches from annalee Roger Dingledine authored 19 years ago	`16) <a href="howitworks.html">How it works</a> <br />`
clean up my meta and br tags Roger Dingledine authored 19 years ago	`17) <a href="download.html">Download</a> <br /> 18) <a href="documentation.html">Documentation</a><br /> 19) <a href="contribute.html">Contribute</a> <br /> 20) <a href="developers.html">Developers</a> <br /> 21) <a href="research.html">Research</a> <br /> 22) <a href="people.html">People</a> <br />`
first cut of new website Roger Dingledine authored 19 years ago	`23) </div><!-- #side --> 24) <div class="main" id="main"> 25)`
give Tor: Overview a differ... Roger Dingledine authored 19 years ago	`26) <h2>Tor: Overview</h2>`
first cut of new website Roger Dingledine authored 19 years ago	`27) 28) <p>`
revised overview text Roger Dingledine authored 19 years ago	`29) Tor is a network-within-a-network that allows people and groups to 30) improve their privacy and security on the Internet. It also enables 31) future software developers to create new kinds of communication tools 32) that have built-in privacy features. Tor can provide the foundation for 33) a whole range of applications that allow organizations and individuals 34) to share information over public networks without compromising their 35) privacy.`
first cut of new website Roger Dingledine authored 19 years ago	`36) </p> 37) 38) <p>`
revised overview text Roger Dingledine authored 19 years ago	`39) Individuals can use Tor to shield themselves and their family members 40) from being tracked by remote websites. They can also use it to connect 41) to resources such as news sites or instant messaging services that are 42) blocked by their local Internet service providers (ISPs).`
first cut of new website Roger Dingledine authored 19 years ago	`43) </p> 44) 45) <p>`
revised overview text Roger Dingledine authored 19 years ago	46) Groups such as the German "Diabetes People" organization recommend Tor 47) for safeguarding their members' online privacy and security. Activist 48) groups like the Electronic Frontier Foundation (EFF) are supporting 49) Tor's development as a mechanism for maintaining civil liberties online. 50) Corporations are investigating Tor as a safe way to conduct competitive 51) analysis, and are considering using Tor to test new experimental projects 52) without associating their names with these projects. A branch of the 53) US Navy uses Tor for open source intelligence gathering, and one of its 54) teams used Tor while deployed in the Middle East recently.
first cut of new website Roger Dingledine authored 19 years ago	`55) </p> 56) 57) <p>`
revised overview text Roger Dingledine authored 19 years ago	58) The variety of people who use Tor is actually part of what makes it 59) so secure. The more populous and diverse the user base for Tor is, 60) the more your anonymity will be protected. 61) </p> 62) 63) <h3>Why We Need Tor</h3> 64) 65) <p> 66) Using Tor protects you against a common form of Internet surveillance 67) known as "traffic analysis." Traffic analysis can be used to infer 68) who is talking to whom over a public network. Knowing the source 69) and destination of your Internet traffic allows others to track your 70) behavior and interests. This can impact your checkbook if, for example, 71) an e-commerce site uses price discrimination based on your country or 72) institution of origin. It can even threaten your job and physical safety
make it clearer there's mor... Roger Dingledine authored 19 years ago	`73) by revealing who and where you are. For example, someone travelling 74) abroad who connects to their employer's computers to check or send mail 75) or for other reasons will reveal her national origin and professional 76) affiliation to any local observing the network even if the connection 77) is encrypted.`
revised overview text Roger Dingledine authored 19 years ago	78) </p> 79) 80) <p> 81) How does traffic analysis work? Internet data packets have two parts: 82) a data payload, and a header used for routing. The data payload is 83) whatever is being sent, whether that's an email message, a web page, or an 84) audio file. Even if you encrypt the data payload of your communications, 85) traffic analysis still reveals a great deal about what you're doing and, 86) possibly, what you're saying. That's because it focuses on the header, 87) which discloses source, destination, size, timing, and so on. 88) </p> 89) 90) <p> 91) A basic problem, for the privacy minded, is that the recipient of your 92) communications can see who sent them by looking at headers. So can 93) authorized intermediaries like Internet service providers, and sometimes 94) unauthorized intermediaries as well. A very simple form of traffic 95) analysis might involve sitting somewhere between sender and recipient on 96) the network, looking at headers. 97) </p> 98) 99) <p> 100) But there are also more powerful kinds of traffic analysis. Some 101) attackers spy on multiple parts of the Internet and use sophisticated 102) statistical techniques to track the communications patterns of many 103) different organizations and individuals. 104) </p> 105) 106) <h3>The Solution: a Distributed, Anonymous Network</h3> 107) 108) <p> 109) Tor helps to reduce the risks of both simple and sophisticated traffic 110) analysis by distributing your transactions over several places on the 111) Internet, so no single point can link you to your destination. The idea 112) is similar to using a twisty, hard-to-follow route in order to throw off 113) somebody who is tailing you -- and then periodically erasing your 114) footprints. Instead of taking a direct route from source to 115) destination, data packets on the Tor network take a random pathway 116) through several servers that cover your tracks so no observer at any 117) single point can tell where the data came from or where it's going. 118) </p> 119) 120) <p> 121) To create a private network pathway with Tor, the user's software or 122) client incrementally builds a circuit of encrypted connections through 123) servers on the network. The circuit is extended one hop at a time, and 124) each server along the way knows only which server gave it data and which 125) server it is giving data to. No individual server will ever know the 126) complete path that a data packet has taken. The client negotiates a 127) separate set of encryption keys for each hop along the circuit to ensure 128) that each hop can't see what these connections are as they pass through.
first cut of new website Roger Dingledine authored 19 years ago	`129) </p> 130) 131) <p> 132) [Insert snazzy onion diagram here.] 133) </p> 134) 135) <p>`
revised overview text Roger Dingledine authored 19 years ago	136) Once a circuit has been established, many kinds of data can be exchanged 137) and several different sorts of software applications can be deployed 138) over the Tor network. Because each server sees no more than one hop in 139) the circuit, neither an eavesdropper nor a compromised server can use 140) traffic analysis to link the connection's source and destination. Tor 141) only works for TCP streams and can be used by any application with SOCKS 142) support. 143) </p> 144) 145) <p> 146) For efficiency, the Tor software uses the same circuit for connections 147) that happen within the same minute or so. Later requests are given a 148) new circuit, to keep people from linking your earlier actions to the new 149) ones.
first cut of new website Roger Dingledine authored 19 years ago	`150) </p> 151)`
revised overview text Roger Dingledine authored 19 years ago	`152) <h3>Hidden Services</h3> 153)`
first cut of new website Roger Dingledine authored 19 years ago	`154) <p>`
revised overview text Roger Dingledine authored 19 years ago	155) Tor also makes it possible for users to hide their locations while 156) offering various kinds of services, such as web publishing or an instant 157) messaging server. Using Tor "rendezvous points," other Tor users can 158) connect to these hidden services, each without knowing the other's 159) network identity. This hidden service functionality could allow Tor 160) users to set up a website where people publish material without worrying 161) about censorship. Nobody would be able to determine who was offering 162) the site, and nobody who offered the site would know who was posting to it.
first cut of new website Roger Dingledine authored 19 years ago	`163) </p>`
revised overview text Roger Dingledine authored 19 years ago	`164) 165) <h3>Staying Anonymous</h3>`
first cut of new website Roger Dingledine authored 19 years ago	`166) 167) <p>`
revised overview text Roger Dingledine authored 19 years ago	`168) Of course, Tor can't solve all anonymity problems. It focuses only on 169) protecting the transport of data. You need to use protocol-specific 170) support software if you don't want the sites you visit to see your 171) identifying information. For example, web proxies such as Privoxy can 172) be used while web browsing to block cookies and withhold information 173) about your browser type.`
first cut of new website Roger Dingledine authored 19 years ago	`174) </p> 175) 176) <p>`
revised overview text Roger Dingledine authored 19 years ago	177) Also, to protect your anonymity, be smart. Don't provide your name 178) or other revealing information in web forms. Be aware that like all 179) anonymizing networks that are fast enough for web browsing, Tor does not 180) provide protection against end-to-end timing attacks: if your attacker 181) can watch the traffic coming out of your computer, and also the traffic 182) arriving at your chosen destination, he can use statistical analysis to 183) discover that they are part of the same circuit. 184) </p> 185) 186) <h3>The Future of Tor</h3> 187) 188) <p>
make usability/security dis... Roger Dingledine authored 19 years ago	189) Providing a usable anonymizing network on the Internet today is 190) an ongoing challenge. We want software that meets users' needs. 191) And we also want to keep the network up and running in a way that 192) handles as many users as possible. Security and usability don't have 193) to be at odds: as Tor's usability increases, it will attract more 194) users, which will increase the possible sources and destinations 195) of each communication, thus increasing security for everyone. 196) We're making progress, but we need your help. Please consider 197) <a href="cvs/tor/doc/tor-doc.html#installing">installing</a> 198) a <a href="cvs/tor/doc/tor-doc.html#server">server</a>
revised overview text Roger Dingledine authored 19 years ago	`199) or <a href="contribute.html">volunteering</a> as a <a 200) href="developers.html">developer</a>.`
first cut of new website Roger Dingledine authored 19 years ago	`201) </p> 202) 203) <p>`
try out a better takeaway m... Roger Dingledine authored 19 years ago	`204) Anonymity is threatened as never before by trends in law, policy, and 205) technology that are undermining our ability to speak and read freely`
make it clearer there's mor... Roger Dingledine authored 19 years ago	`206) online without being forced to reveal who we are. These trends also 207) undermine national security and critical infrastructures by making 208) personal, corporate, organization, and government communications more 209) vulnerable. With each new user and server, we enhance Tor's ability`
clean up other phrasing Roger Dingledine authored 19 years ago	`210) to restore your control over your security and privacy.`
first cut of new website Roger Dingledine authored 19 years ago	`211) </p> 212) 213) </div><!-- #main -->`
decide on a format for cont... Roger Dingledine authored 19 years ago	`214) <div class="bottom" id="bottom"> 215) <i><a href="mailto:tor-webmaster@freehaven.net">Webmaster</a></i> - 216) $Id$ 217) </div>`