CaSCaDE: (Time-Based) Cryptography from Space Communications DElay
Abstract
In a world where cryptographic constructs are stuck in a race against faster algorithms, we propose a cosmic solution: why not root cryptographic provable delays in the speed of light? This paper introduces Sequential Communication Delay (SCD) in the Universal Composability framework, a functionality models communication channels where data is transmitted fashionably late. With our SCD proofs, we proposed the first constructions of a Verifiable Delay Function and a Publicly Verifiable Time-Lock Puzzle that do not rely on computational assumptions Say goodbye to the worries of computational speed-ups and hello to a time-delay rooted in the cosmos!
Elena Pagnin is an assistant professor at the CSE department at Chalmers, leading the Cryptoteam. Her research is focused on cryptography and security, with a special interest for homomorphic cryptosystems, data authentication and user privacy. Prior to joining Chalmers, Elena has been an assistant professor at Lund University, and before that, a postdoctoral researcher in the crypto group at Aarhus University. Elena completed her PhD at Chalmers in 2019. Her motto is: det är lätt att vara efterklok (it’s easy to be wise in hindsight).