On June 9, 2020, Jiseung Kim (김지승) from KIAS presented a talk on some aspects of cryptography, including his recent work “Adventures in Crypto Dark Matter: Attacks, Fixes, and Analysis of weak PRF” jointly with Jung Hee Cheon, Wonhee Cho, and Jeong Han Kim. The title of his talk was “Hardness and concrete security in cryptography“.
Computationally hard problems have been widely used to construct cryptographic primitives such as encryptions, digital signatures. For example, provably secure primitives are based on a reduction from the hardness problems. However, the concrete instantiation of primitives does not follow the results of hardness problems due to its efficiency. In this talk, we introduce cryptographic hardness problems widely used in cryptography and the gap between hardness results and concrete security of cryptographic primitives based on our recent works.