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MassBrowser
Unblock cking the Censored Web fo for the Masses, by the Masses
Milad Nasr, Hadi Zolfaghari, Amir Houmansadr, Amirhossein Ghafari University of Massachusetts, Amherst
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Internet Censorship
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MassBrowser Unblock cking the Censored Web fo for the Masses, by - - PowerPoint PPT Presentation
MassBrowser Unblock cking the Censored Web fo for the Masses, by - - PowerPoint PPT Presentation
MassBrowser Unblock cking the Censored Web fo for the Masses, by the Masses Milad Nasr, Hadi Zolfaghari, Amir Houmansadr, Amirhossein Ghafari University of Massachusetts, Amherst 1 Internet Censorship 2 Censorship Circumvention Tools 3
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Censorship Circumvention Tools
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Shortcomings of Current Designs
Easy to Block Costly Poor QoS No User- Control Hard to Deploy
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Key Reason: They Bundle Properties
Circumvention Privacy Anonymity
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Our Observation: The Mass of Users Just Want Circumvention
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Our Approach
Design a System Optimized for Circumvention
Privacy/Anonymity provided optional
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MassBrowser
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- Optimizing load on proxies
- Volunteer based proxies
- Clients help other clients
- User-adjustable privacy/anonymity
- Incentivizing volunteers
- Cost optimization
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Key Design Principles
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- Optimizing load on proxies
- Volunteer based proxies
- Clients help other clients
- User-adjustable privacy/anonymity
- Incentivizing volunteers
- Cost optimization
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Key Design Principles
Optimizing only
- n circumvention
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- Optimizing load on proxies
- Volunteer based proxies
- Clients help other clients
- User-adjustable privacy/anonymity
- Incentivizing volunteers
- Cost optimization
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Key Design Principles
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Proxy-based Systems
PNG from FreePik
Block it!
Proxy Destination
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CacheBrowsing
Contents on CDN
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twitter.com
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Optimizing Load on Proxies
MassBrowser
No
Connect Directly
Is Censored?
Yes
Is CacheBrowsable?
Yes
CacheBrowse Proxy through Buddy
Content Publisher CDN Server
Buddy
Encryption and Obfuscation
www.bbc.com
Client
Operator
HTTPS Channel CacheBrowsing
Controlling signals PolicyManager
SessionManager
Available Session
No Request a new Session Yes
CDN
Yes No
Is MassBrowsable? Proxy Tor through MassBrowser
Proxy via Buddies 14
41% of Top 1000 Alexa website contents are cache browsable
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- Optimizing load on proxies
- Volunteer based proxies
- Clients help other clients
- User-adjustable privacy/anonymity
- Incentivizing volunteers
- Cost optimization
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Key Design Principles
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Operator
Censored Region 1
Clients Clients
Censored Region 2
Buddies
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China Turkey
Open Internet
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Clients Helping Each Other!
5 10 15
Countries
0.0 0.2 0.4 0.6 0.8 1.0
Cumulative Fraction
Any News Political Personal Websites Pornography Extremist
More than 60%
- f censored
contents are country specific About 90% of political and news censored contents are country specific
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An Example!
27852 1564 91 156 29 205 18
China Iran Turkey
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*Top 1M websites
Only 18 websites are blocked in all three
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- Optimizing load on proxies
- Volunteer based proxies
- Clients help other clients
- Incentivizing volunteers
- User-adjustable privacy/anonymity
- Cost optimization
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Key Design Principles
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Incentivizing Volunteer Proxies
Buddies can whitelist! Buddies can control usage!
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- Optimizing load on proxies
- Volunteer based proxies
- Clients help other clients
- Incentivizing volunteers
- User-adjustable privacy/anonymity
- Cost optimization
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Key Design Principles
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- Cost:
- MassBrowser is about 200 times cheaper than Tor’s
meek
- Performance:
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Users Can Trade off QoS vs. Privacy
*experiments done in Iran
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The Current State
- f The Project
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- Near three years of active development!
- 100K lines of code
- More than 10 people helped in the development
- Undergoing code review and security audit by a
third-party
- Internationalization is undergoing
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Development Status
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Working Client and Buddy
Coming Soon!
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Currently Invitation-based Only
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- If you are in an uncensored region:
- Become a Buddy!
- Become an early adopter
- Get involved with the development
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We Need Your Help!
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- “It's very good to use!!!!!!”
- “It's very very interesting and amazing~”
- “Hello, I am in China. I am using mass browser and tor
browser now. Now I can use the websites blocked by the Chinese government, and the speed is very good. Thank you very much.”
- “Great relaying capability!”
- “Great, works really well!”
- …
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Thanks to so many people who helped in the testing and development of MassBrowser
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COMPUTING FOR THE COMMON GOOD
Milad Nasr milad@cs.umass.edu https://people.cs.umass.edu/~milad/ | @srxzr
MassBrowser.cs.umass.edu @massbrowser Join us!
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Domain Fronting
Destination
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