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May/June 2009

Dissent Made Safer

How anonymity technology could save free speech on the Internet.

By David Talbot

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"Sokwanele" means "enough is enough" in a certain Bantu dialect. It is also the name of a Zimbabwean pro-democracy website whose bloggers last year published accounts of atrocities by Robert Mugabe's regime and posted Election Day updates describing voter intimidation and apparent ballot stuffing. You can visit Sokwanele's "terror album" and see photographs: of a hospitalized 70-year-old woman who'd been beaten and thrown on her cooking fire (she later died, the site says); of firebombed homes; of people with deep wounds carved into their backs. You can find detailed, frequently updated maps describing regional violence and other incidents. You will be confronted with gruesome news, starkly captioned: "Joshua Bakacheza's Body Found."

Anonymizer: Roger Dingledine is project leader of Tor, a system that obscures the true origin and destination of Internet communications.
Credit: Chris Crisman
Multimedia
video  Watch Roger Dingledine explain how Tor works.
video  See an interactive demo of Tor.
Reporters Notebook: David Talbot

Hear how meeting with project leader Roger Dingledine proved almost as difficult as tracking data through the Tor network.

Because this horrific content is so readily available, it is easy to overlook the courage it took to produce it. The anonymous photographers and polling-station bloggers who uploaded the Sokwanele material remain very much in danger. In a place like Zimbabwe, where saying the wrong thing can get you killed or thrown in prison on treason charges, you take precautions: you're careful about whom you talk to; you're discreet when you enter a clinic to take pictures. And when you get to the point of putting your information on the Internet, you need protection from the possibility that your computer's digital address will be traced back to you. Maybe, at that point, you use Tor.

Tor is an open-source Internet anonymity system--one of several systems that encrypt data or hide the accompanying Internet address, and route the data to its final destination through intermediate computers called proxies. This combination of routing and encryption can mask a computer's actual location and circumvent government filters; to prying eyes, the Internet traffic seems to be coming from the proxies. At a time when global Internet access and social-networking technologies are surging, such tools are increasingly important to bloggers and other Web users living under repressive regimes. Without them, people in these countries might be unable to speak or read freely online (see "Beating Surveillance and Censorship").

Unlike most anonymity and circumvention technologies, Tor uses multiple proxies and encryption steps, providing extra security that is especially prized in areas where the risks are greatest. Paradoxically, that means it's impossible to confirm whether it's being used by the Zimbabwean bloggers. "Anyone who really needs Tor to speak anonymously isn't going to tell you they use Tor to speak anonymously," says Ethan Zuckerman, cofounder of Global Voices, an online platform and advocacy organization for bloggers around the world. "You can't tell if it's happening, and anyone who is actively evading something isn't going to talk about it." That said, the ­Sokwanele journalists "are extremely sophisticated and use a variety of encryption techniques to protect their identity," he says.

Story continues below

Anonymity aside, Internet users in dozens of countries--whether or not they are activist bloggers--often need to evade censorship by governments that block individual sites and even pages containing keywords relating to forbidden subjects. In 2006, the OpenNet Initiative--a research project based at Harvard and the Universities of Toronto, Oxford, and Cambridge that examines Internet censorship and surveillance--discovered some form of filtering in 25 of 46 nations tested, including China, Saudi Arabia, Iran, and Vietnam.

In a new and still-evolving study, OpenNet found that more than 36 countries are filtering one or more kinds of speech to varying degrees: political content, religious sites, pornography, even (in some Islamic nations) gambling sites. "Definitely, there is a growing norm around Internet content filtering," says Ronald Deibert, a University of Toronto political scientist who cofounded OpenNet. "It is a practice growing in scope, scale, and sophistication worldwide."

Comments

  • Clearing up a few points
    A few clarifications of points made in this generally good article about the design and uses of Tor:

    1. It is true that the versions of onion routing we designed before designing Tor "never left the lab", but only in the sense that the public prototype ran on machines entirely at the Naval Research Laboratory. During its operation from 1997 to early 2000, over twenty million requests from more than sixty countries and all major US top level domains were processed by the initial prototype onion routing network. An average of over 50,000 hits per day occurred during the final year. Peak reported load of 84,022 connections occurred on 12/31/98.

    2. Many improvements and realizations stemmed from the collaboration with Roger Dingledine and Nick Mathewson that led to Tor,  but "that tools for protecting military agents and tools for protecting Web surfers' privacy could be one and the same" was recognized from the very beginning of onion routing, and several early design and deployment decisions arose from it. For example, encouraging public usage by allowing public verification of trust was one of the motivations to go open source, as it later came to be called. The first publication release for onion routing code was in 1996.
    Rate this comment: 12345

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