On the Feasibility of a Censorship Resistant Decentralized Name - - PowerPoint PPT Presentation

On the Feasibility of a Censorship Resistant Decentralized Name System

Matthias Wachs Martin Schanzenbach Christian Grothoff

Technische Universit¨ at M¨ unchen

The Sixth International Symposium on Foundations & Practice of Security FPS’2013 La Rochelle, France

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Where We Are

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Adversary Model

◮ Any role ◮ Multiple Identities ◮ Computational Power ◮ Legal Power

But cannot:

◮ Break or prevent crypto ◮ Attack user systems ◮ Prevent network communication

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Broken Pillars

Web Social Messaging Encryption T elephony Public Key Infrastructure

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Broken Pillars

Web Social Messaging Encryption T elephony Public Key Infrastructure

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Zooko’s Triangle

Secure Global Memorable

A name system can only fulfill two!

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Zooko’s Triangle

Secure Global Memorable Hierarchical Registration C r y p t

• g

r a p h i c I d e n t i fi e r s Petname Systems

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Zooko’s Triangle

Secure Global Memorable Hierarchical Registration C r y p t

• g

r a p h i c I d e n t i fi e r s Petname Systems

mnemonic URLs c e r t i fi c a t e s S D S I

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Petnames and SDSI

PUBAlice PUBCarol PUBBob bob carol bob's carol

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Requirements

◮ Censorship Resistance by Decentralization

⇒ Peer-to-Peer, DHT

◮ Verification

⇒ Signatures

◮ Query Privacy

⇒ Encryption

◮ Integration with DNS

⇒ Coexisting Namespaces

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Challenges

◮ Legacy Applications

⇒ Proxies

◮ Censorship in other Layers

⇒ Tor

◮ Usability

⇒ DNS look-a-like, QR Code

Bob Builder, Ph.D. Address: Country, Street Name 23 Phone: 555-12345 Mobile: 666-54321 Mail: bob@tum.gnu 11 / 12

End

Thank you! schanzen@in.tum.de wachs@net.in.tum.de grothoff@net.in.tum.de Get the code: https://gnunet.org/gns

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