1. Privacy Protecting Technologies

2. Technology: Value Neutral? Does technology, on average, help or hinder personal privacy?

3. The Big Idea We can use technology to improve privacy

4. Web Browsing Ad-Subtract Bugnosis

5. Ad Subtract

8. “Search Sanity”

9. Ad Subtract: Client-Side Java Proxy Advantages: –Multiplatform –Easy to debug –Client/server Disadvantages: –Doesn’t work with SSL –Install footprint –Need to parse HTML

10. Bugnosis

11. Features: –Browser helper object –Accesses HTTP & HTTPS –Downloads updates –Designed for journalists

12. Private Messaging PGP – first generation Hush Mail – web based The Martus Project – application specific Disappearing Ink (Omniva) - Deletion

13. PGP Add-on Plug-in S/MIME vs. OpenPGP Political Baggage

14. Hush Mail Second-generation Web-based Java Crypto Client

15. Hush Mail

19. Hush Mail Interface

20. HushMail Diagram

21. Disappearing Ink / Omniva Self-destructing email for people who want to use it. Why bother? Because it’s hard to delete things

22. Email gets copies a lot

26. Mix-Nets, Web & IP transport Chaum’s mix-net scheme The big idea: anonymity needs company 1 mix: you trust the mixer More mixes -> Less Trust Mixing needs to be in space and time

27. Practical applications of mixers: Anonymous Remailers Anonymous Browsing Anonymous Publishing

28. Anonymous Remailers Anonymous posting on Usenet anon.penet.fi –Based in Finland –Operated by Julf Helsingius –70,000 registered users; 10,000 messages/day –February 1995 – Church of Scientology demands the True Name of a nym an144108@anon.penet.fian144108@anon.penet.fi –Revealed on February 8 to belong to tc@alumni.caltech.edu under order from Finish Courttc@alumni.caltech.edu –(Information applied to the Finish court had apparently been somewhat misleading) –August 30 – After second court case, anon.penet.fi shut down –full details at www.xs4all.nl/~kspaink/cos/rnewman/anon/penet.html www.xs4all.nl/~kspaink/cos/rnewman/anon/penet.html

29. Craig’s List

30. Key features of an anonymous remailer Strips identity from messages passing through Provides mapping of nyms to “true names” –But only if replies are important Optional: –Mixing - only if traffic in and out is observable –Encryption -

31. Anonymous Web Browsing Web Caches Anonymizer Anonymous Transport Services: –Freedom –Onion Routing

32. Web Caches cache-ntc-ah12.proxy.aol.com - - [10/May/2003:22:47:31 -0400] "GET /clips/1999.TR.LCS35-FountainOfIdeas.pdf HTTP/1.0" 200 65536 "http://aolsearch.aol.com/aol/search?query=fountain+ideas&page=2" "Mozilla/4.0 (compatible; MSIE 6.0; AOL 7.0; Windows NT 5.1;.NET CLR 1.0.3705)“ cache-ntc-ah12.proxy.aol.com - - [10/May/2003:22:47:39 -0400] "GET /clips/1999.TR.LCS35-FountainOfIdeas.pdf HTTP/1.1" 206 688128 "-" "Mozilla/4.0 (compatible; MSIE 6.0; AOL 7.0; Windows NT 5.1;.NET CLR 1.0.3705)“ cache-ntc-ah12.proxy.aol.com - - [10/May/2003:22:47:44 -0400] "GET /clips/1999.TR.LCS35-FountainOfIdeas.pdf HTTP/1.1" 206 1024 "-" "Mozilla/4.0 (compatible; MSIE 6.0; AOL 7.0; Windows NT 5.1;.NET CLR 1.0.3705)“ cache-ntc-ah12.proxy.aol.com - - [10/May/2003:22:47:47 -0400] "GET /clips/1999.TR.LCS35-FountainOfIdeas.pdf HTTP/1.1" 206 75 "-" "Mozilla/4.0 (compatible; MSIE 6.0; AOL 7.0; Windows NT 5.1;.NET CLR 1.0.3705)“ cache-ntc-ah12.proxy.aol.com - - [10/May/2003:22:47:52 -0400] "GET /clips/1999.TR.LCS35-FountainOfIdeas.pdf HTTP/1.1" 206 725650 "-" "Mozilla/4.0 (compatible; MSIE 6.0; AOL 7.0; Windows NT 5.1;.NET CLR 1.0.3705)"

33. Cache with anonymity

34. Anonymizer

35. Anonymizer.com rewrites URLs <td width=90 style='background:aqua; text-align:center; font:bold; font-family:Arial'> Photos <td width=90 style='background:lime; text-align:center; font:bold; font-family:Arial'> Pubs <td width=90 style='background:magenta; text-align:center; font:bold; font-family:Arial'> Projects

36. Private IP Transport Onion Routing Freedom

38. Unresolved Issues How do you buy a book anonymously?

39. [Anonymous] Publication Systems anon.penet.fi was really about the right to anonymous publication on Usenet (1996) Napster (1999 – 2001) Freenet

40. References: EPIC Online Guide to Privacy Protecting tools: http://www.epic.org/privacy/tools.html