Roger Dingledine will speak on global internet censorship on Tuesday, April 12, 2010 from 2 p.m. – 3 p.m. at George Pearl Hall room 101.

His talk is titled "Tor and Censorship: Lessons Learned." The talk is sponsored by the UNM Computer Science Department and the Regent's Speaker Endowment.

Dingledine is project leader for The Tor Project, a US non-profit working on anonymity research and development for such diverse organizations as the US Navy, the Electronic Frontier Foundation, and Voice of America. In addition to all the hats he wears for Tor, Roger organizes academic conferences on anonymity, speaks at a wide variety of industry and hacker conferences, and also does tutorials on anonymity for national and foreign law enforcement.

Tor is a free-software anonymizing network that helps people around the world use the Internet in safety. Tor's 1600 volunteer relays carry traffic for several hundred thousand users including ordinary citizens who want protection from identity theft and prying corporations, corporations who want to look at a competitor's website in private, and soldiers and aid workers in the Middle East who need to contact their home servers without fear of physical harm.

Tor was originally designed as a civil liberties tool for people in the West. But if governments can block connections *to* the Tor network, who cares that it provides great anonymity?

A few years ago designers started adapting Tor to be more robust in countries like China. They streamlined its network communications to look more like ordinary SSL, and introduced "bridge relays" that are harder for an attacker to find and block than Tor's public relays.

In the aftermath of the Iranian elections in June, and then the late September blockings in China, the network designers learned a lot about how circumvention tools work in reality for activists in tough situations.

Dingledine will give an overview of the Tor architecture, and summarize the variety of people who use it and what security it provides. Then he will focus on the use of tools like Tor in countries like Iran and China: why anonymity is important for circumvention, why transparency in design and operation is critical for trust, the role of popular media in helping -- and harming -- the effectiveness of the tools, and tradeoffs between usability and security.

After describing Tor's strategy for secure circumvention (what we *thought* would work), he will talk about how the arms race actually seems to be going in practice.

Media contact: Karen Wentworth (505) 277-5627;