1. SkypeMorph: Protocol Obfuscation for Tor Bridges
Hooman Mohajeri Moghaddam Baiyu Li  Mohammad Derakhshani. Ian Goldberg
Presented by Ganbi

2. Outline
Overview
Problem
Solution
Questions

3. Anonymity Is it Important? Answer: Tor People’s lives depend on it
Authoritative Government vs. Activist Groups
Syria, Egypt, China
Answer: Tor

4. Tor Overview

5. Tor Overview

6. Tor Overview

7. Tor Problem
The public list of Tor relay nodes can give away all the IP addresses.
To fix, developers added “bridge”

8. Tor Problem

9. Tor Problem
Bridge

10. 4 Ways to get Bridge IP
will tell you few based on your IP address and location
Mail
Via social network
You can set up your own and tell your target users directly

11. Problem Slowly China was able to block most Bridges by probing
DPI (deep packet inspection) is still possible

12. Solution/Paper Pluggable transports SkypeMorph
Disguise the Tor packets to look like Skype traffic by using already existing Skype VoIP protocol and user authentication system.

13. Solution
Bridge

14. Advantages Anyone can use, it’s free!
Can transfer reasonable size of data = no bottleneck
Encryption already built in
In order to stop Tor, they also have to stop legitimate Skype calls, which is highly unlikely
Another big advantage: Harder to block bridges even after they are found

15. Two Methods

16. Two Methods

17. Works Cited
Moghaddam, Li, Derakhshani, and Goldberg "SkypeMorph: Protocol Obfuscation for Tor Bridges" (n.d.): n. pag. Print.