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 1 / 12

Where We Are 2 / 12

Adversary Model ◮ Any role ◮ Multiple Identities ◮ Computational Power ◮ Legal Power But cannot: ◮ Break or prevent crypto ◮ Attack user systems ◮ Prevent network communication 3 / 12

Broken Pillars T elephony Messaging Web Social Encryption Public Key Infrastructure 4 / 12

Broken Pillars T elephony Messaging Web Social Encryption Public Key Infrastructure 5 / 12

Zooko’s Triangle Secure Global Memorable A name system can only fulfill two ! 6 / 12

Zooko’s Triangle Secure s r e fi i Petname Systems t n e d I c i h p a r g o t p y r C Global Hierarchical Registration Memorable 7 / 12

Zooko’s Triangle Secure s r e fi i Petname Systems t n e d I c i h mnemonic p a I S r URLs D S g o t p y r C s e t a c fi i t r e c Global Hierarchical Registration Memorable 8 / 12

Petnames and SDSI PUB Alice bob PUB Bob bob's carol carol PUB Carol 9 / 12

Requirements ◮ Censorship Resistance by Decentralization ⇒ Peer-to-Peer, DHT ◮ Verification ⇒ Signatures ◮ Query Privacy ⇒ Encryption ◮ Integration with DNS ⇒ Coexisting Namespaces 10 / 12

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 12 / 12