Sofya Rozenblat 11/26/2012 CS 105 TOR ANONYMITY NETWORK

 A brief introduction  What is TOR?  History of TOR’s development  Why is TOR useful?  How does it work?  Some drawbacks  The importance of TOR around the world  How you can get involved OVERVIEW

A BRIEF INTRODUCTION

 TOR=The Onion Router  Refers to layered encryption and re- encryption  Free, open source software for Windows, Mac, Linux/Unix, and Android (cross- platform)  Used with web browsers, instant messaging clients, remote login  Written in C  ~146,000 lines of source code WHAT IS TOR?

 Formed in 2011 by 2 MIT students in conjunction with a US Navy Laboratory  Currently developed by the Tor Project  Research-education nonprofit organization  Based in Walpole, MA DEVELOPMENT OF TOR

 Your online activity can be traced to your IP address even if you visit encrypted websites  Networks see websites you visit and these websites know your IP address  Requires no complex configuration to run and is free!  TOR is one solution to the lack of privacy and anonymity  Countries where censorship is widespread  Spreading political activism and political/social reform without fear of censorship WHY IS TOR USEFUL?

 Internet traffic routed through random relays (volunteers) until it arrives at the destination  Indirect route from source to destination  Prevents service provider from monitoring visited websites  IP address remains anonymous  Incremental encrypted circuit HOW DOES IT WORK?

No individual relay knows the complete circuit-ensures anonymity.

Same circuit used for connections within 10 minute intervals only. Provides an added layer of security

 Because of multiple relays, browsing is significantly slower through Tor than a normal browser  Downloading large files is a time consuming process  Still possible for the internet to remain censored if government blocks relays and bridges SOME DRAWBACKS

 Currently used by: journalists, law enforcement officials, activists, the military  Surveilling the web without leaving government IP addresses in logs  Allows civil liberties groups and whistleblowers to communicate with journalists  Those living in repressive regimes fraught with censorship can access the web  Used by WikiLeaks  Allowed Egyptians to access internet at the height of violence and civil unrest in 2011 TOR AROUND THE WORLD

 Donate bandwith  Spin a bridge  Run a relay  Be an exit relay  Visit for more informationwww.torproject.org HOW TO GET INVOLVED WITH THE TOR PROJECT

QUESTIONS?