A One Round Protocol for Tripartite Diffie Hellman By Dane Vanden Berg
● Antoine Joux ● New form of an old Cryptographic Method ● Based off of ECDHE - Elliptic Curve Diffie Hellman Ephemeral Paper Abstract
● Cryptographical uses in day to day ● Brief introduction on Diffie-Hellman Protocol ● Elliptic Curve Cryptography ● One Round Protocol For Tripartite Diffie-Hellman Full Ground
● ● Secure Websites ● Online Signatures ● Purchases Cryptography and You
● Discovered in 1976 ● the Diffie–Hellman protocol is one of the most famous cryptographic primitives. ● Intended for a shared secrecy of one key ● Intended for perfect forward secrecy ● ( a.k.a Trapdoor Function? ) What is Diffie Hellman
Backround Diffie Hellman Merkle
Diffie Hellman Merkle Example BobEveAlice b = 10g=5a = 8 p=23 B=5 10 mod 23A=5 8 mod 23 B=9 A=16 s=16 10 mod 23s=9 8 mod 23 s= 13s=13 B=9 A=16
Another approach to public key cryptography ECC - Elliptic curve cryptography
p: field parameters (modulo p) a,b: points on the curve G: Generator - cyclic group n: ord(G) - number of pts in G h: cofactor - should equal 1 Domain Parameters
Example
● Shorter Encryption Key ● Fewer Resources ● Compare how much energy it takes to break a crypto algorithm and compare it to how much water you can boil. Why Elliptic Curves
Tripartite Diffie Hellman
● Involves 3 participants ● Single pass of communications ● 1 can broadcast some data to other 2 Description
● Allows for 3 people instead of 2 ● Only one round of communication ● Broadcasting doesn’t require all parties to be “alive” at once ● Trusted Third Party Pros
Example of Trusted Third Party
● Open to middle man attacks ● If keys aren’t certified people aren’t sure who is who. Flaws
easy-to-understand-primer-on-elliptic- curve-cryptography/ Joux, Antoine. “A One Round Protocol for Tripartite Diffie-Hellman.” Journal of Cryptology 17.4(2004):n. pag. Web Work Cited