Towards Tightly Secure Lattice Short Signature and Id Based Encryption

Explore a talk from Asiacrypt 2016 by Xavier Boyen and Qinyi Li on tightly secure lattice short signatures and ID-based encryption. Delve into the motivations behind tight security reductions and examine the theorem template for breaking computational problems. Investigate digital signatures, focusing on the Katz-Wang magic bit technique and the Short Integer Solution (SIS) problem with trapdoors. Learn about Boyen's signature proof idea and the presenters' proposed signature scheme. Gain insights into advanced cryptographic concepts and their applications in secure communication systems.

Intro
Motivations
Tight Security Reductions Theorem (template) If an adversary A(t.e)-breaks the scheme II in the defined security model, there exists an algorithm that (t',')-breaks some computation problem
Digital Signatures
Our Method
Katz-Wang's Magic Bit KW'03
Short Integer Solution (SIS) Problem and Trapdoors Definition
Proof Idea of Boyen's Signature
Our Signature Scheme
Conclusion