The Twin Diffie-Hellman Problem and Applications

ded abstract of this paper appears in Advances in Cryptology -- EUROCRYPT '08, Lecture Notes in Computer Science Vol. 4965, N. Smart ed., Springer-Verlag, 2008. This is the full version. The Twin Diffie-Hellman Problem and Applications David Cash1 Eike Kiltz2 Victor Shoup3 June 11, 2008 We propose a new computational problem called the twin Diffie-Hellman problem. This problem is closely related to the usual (computational) Diffie-Hellman problem and can be used in many of the same cryptographic constructions that are based on the Diffie-Hellman problem. Moreover, the twin Diffie-Hellman problem is at least as hard as the ordinary Diffie-Hellman problem. However, we are able to show that the twin Diffie-Hellman problem remains hard, even in the presence of a decision oracle that recognizes solutions to the problem -- this is a feature not enjoyed by the ordinary Diffie-Hellman problem. In particular, we show how to build a certain "trapdoor test" that allows us to effec...

• Type: Conference
• Year: 2008
• Where: EUROCRYPT
• Authors: David Cash, Eike Kiltz, Victor Shoup
• Keywords: Cryptology, Diffie-hellman Problem, EUROCRYPT 2008, Ordinary Diffie-hellman Problem, Twin Diffie-hellman Problem