1. Strengthening Tor against Eavesdropping Correlation Attacks Robert Thomas CSCE 727 20 APR 2015 Audio: https://drive.google.com/file/d/0Bwz32a1PN_QuWFN5TVJ1WWprb0k/view?usp=sharinghttps://drive.google.com/file/d/0Bwz32a1PN_QuWFN5TVJ1WWprb0k/view?usp=sharing

2. Tor What is it? Network of Onion Routers Anonymity Tool Why should you care? Anonymity == Privacy “Big Brother is watching” 2

3. Eavesdropping Correlation Attack Observe enough data to statistically infer origin and destination Compromises anonymity Passive Variants Only listen Hard to detect Active Variants Misreport capabilities to attract users to observable nodes Denial of Service on unobservable nodes 3

4. Anonymity vs Performance 4 Related Work General Operate your own node (impacts performance) Cover traffic (impacts performance) Passive Tools to detect ‘odd’ nodes (impacts performance) Obscure routing strategies (impacts performance) Active Bandwidth Verification of potential nodes (only avoids nodes misreporting capabilities) Increased Anonymity protections cost Performance (usually)

5. This Project Provides the Best of Both! Combine individual solutions Bandwidth Verification Operate a Node Cover traffic Cover_traffic = MIN(Sender_available_capacity, Receiver_available_capacity) – (Payload + Buffer_allowance) Experiment Results will validate claims Anonymity measured by dataset size needed for successful correlation attack Performance measured by load test 5