Efficient MDS Diffusion Layers & Cryptanalytic Results on Stream Ciphers

Speaker：Abhishek Kesarwani
Date：Thursday, 2021-03-04 13:30
Zoom ID：388 528 9728 Password：BIMSA
Abstract：

The Lightweight Cryptography (LWC) project is an initiative launched by the National Institute of Standards and Technology (NIST) which aims to create reliable solutions to the problem of securing data in constrained environments. Solutions to these problems are typically given by building symmetric-key primitives that have a small footprint in hardware and/or low computational complexity. Block ciphers and stream ciphers are two main symmetric-key primitives. MDS matrices are used in the design of diffusion layers in many block ciphers and hash functions because they are perfect diffusion layers. But MDS matrices, in general, have costly implementations. Stream cipher is also well suited for applications with low energy consumption. As no formal security proofs exist, confidence in these stream ciphers is largely based on intense cryptanalysis. In the first half of the talk, I will discuss the construction of efficient MDS diffusion layers using an exhaustive method. Then in the second half, I will present some cryptanalysis results on NFSR-based stream ciphers.

About the speaker:

Abhishek Kesarwani is a researcher in the field of symmetric-key cryptography. Recently, he has submitted his thesis for the award of PhD degree from Indian Institute of Technology Madras, Chennai, India, where he is supervised by Dr Santanu Sarkar and Dr Ayineedi Venkateswarlu.