CS Forum: Russell W. F. Lai "Proof systems and Secret Sharing: From Group-land to Lattice-land"

CS forum is a seminar series arranged at the CS department - open to everyone free-of-charge.
CS Forum

Time: Monday 20 Sep at 13:00-14:00
Place: Lecture room T2 in CS building

This is a hybrid event, please register if you wish to attend the talk on site.You can also attend the talk via Zoom (passcode 472317)

Proof systems and Secret Sharing: From Group-land to Lattice-land 

Russell W. F. Lai
Friedrich-Alexander University Erlangen-Nuremberg, Germany


An overwhelming portion of public-key cryptography deployed today is based on the conjectured hardness of computational problems over groups. As these group problems are efficiently solvable using Shor's algorithm on a quantum computer, an ongoing quest in cryptography is to construct cryptographic primitives based on the hardness of computational problems which are believed to be intractable even for quantum computers, such as finding short vectors in lattices. One strategy of doing so is to translate existing group-based constructions into their lattice-based counterparts.

In this talk, I will begin by recalling examples of group-based proof systems and distributed pseudorandom functions. Underneath these constructions are systems of linear equations defined by Vandermonde matrices over prime fields. When translating these constructions to the lattice setting, one encounters the difficulty that the translated Vandermonde systems are now defined over rings and hence not always solvable. I will present recent results towards tackling this very issue.

Russell W. F. Lai


Russell W. F. Lai is a graduating PhD student at the Chair of Applied Cryptography, Friedrich-Alexander University Erlangen-Nuremberg, Germany. His research interests include succinct argument systems, anonymous systems, homomorphic secret sharing, password-based cryptography, multi-channel source coding, and steganography.


Professor Chris Brzuska, Department of Computer Science

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