Internet Censorship (Iran)

1. WEB FILTERING
Internet Censorship
Omid Abbasi (Student at Shiraz University)
1/21

2. Our Goals
• What is the censorship?
• When it started?
• Why ?
• Who started?
• What is the scope of censorship?
• Who censor the internet?
• How does the censorship take place?
• Where is the censorship happening?
• How to get ride of it?
2/21

3. What is internet censorship?
• Internet censorship is essentially a method used by
corporations, governments and others in order to
filter what a user can view on the internet.
3/21

4. Why Started?
4/21

5. Critics
• Families:
• limit what sites their children can access.
• Governments:
• Viewing political pages that are against the ruling party.
• News pages that would inform citizens of conflicts.
• Pages they would deem obscene.
5/21

6. Solution
• Shutdown the internet
• Control publishers
• Control Access
6/21

7. What Countries censors?
Not Free Partially Free
Free No Data 7/21

8. Censor What?
Traditional social values
Political National security
8/21

9. What Iran censors
9/21

10. Types of censorship
What is facebook.com
facebook.com is 173.252.110.20
Hello are you there?
VPS
Give me facebook.com homepage
Normal web browsing
Censorship node
10/21

11. DNS hijacking
What is facebook.com
10.10.34.34
Hello are you there?
VPS
Censorship node
Types of censorship (cont’d)
11/21

12. Address or Port blocking
Hello are you there?
Censorship node
What is facebook.com
facebook.com is 173.252.110.20
Types of censorship (cont’d)
12/21

13. Web content filtering
Hello are you there?
Censorship node
What is facebook.com
facebook.com is 173.252.110.20
Hello are you there?
Types of censorship (cont’d)
13/21

14. Where Internet filtering accrues(Iran)?
14/21

15. When there is a problem
there is a solution
15/21

16. Primary objective
Connect censored users to the uncensored Internet
securely and anonymously.
16/21

17. Anatomy of Anti-Censorship System
17/21

18. Anti censorship methods
http proxy
18/21

19. CGI proxy
phproxy
James Marshall
Anti censorship methods (cont’d)
19/21

20. IP tunneling (VPN)
In IP tunneling, every IP packet, including addressing
information of its source and destination IP networks,
is encapsulated within another packet format native
to the transit network.
Anti censorship methods (cont’d)
20/21

21. 21/21