# Fully Homomorphic Encryption Part Two: Lattice-based Crypto and the LWE Problem

Last time, we went through the overview of what FHE is, the different stages towards FHE, and the brief history of it. I think at this point, we should be pretty comfortable with understanding what FHE is and its potential applications.

Although these topics might sound pretty archaic and distant, I claim that it’s actually not that hard to understand. In fact, with just simple knowledge in linear algebra, we can fully grasp the idea of the GSW FHE Scheme.

In this post, let’s together review some fundamental concepts of Lattice-based Crypto and the LWE Problem so we can build up our knowledge to the actual GSW Scheme later. …

# Fully Homomorphic Encryption Part One: A Gentle Intro

This post is mirrored on my personal blog: Function Decomposition.

Recently I have taken CS355 (Topics in Cryptography) at Stanford. This was a comprehensive course on advanced crypto topics.

Throughout the 3-month course, the instructors covered various topics that span the history of Cryptography, starting from One-way Functions, PRFs all the way to applied cryptosystems such as MPC, Zero-Knowledge, and PIR. This was really a great course to take, and I’ve surely learned a lot about modern cryptosystems.

In order to strengthen my understanding of these topics, I’ve decided to start a series of blog posts that (gently) introduces these cool crypto topics. I’ll be summarizing lecture notes and paraphrase them into my own words. …

# Mesmerizing Chameleon Signatures

For the past year, I having been taking classes at Stanford under Professor Dan Boneh and learning about different topics in the field of Cryptography. It has truly become an amazing journey. There are so many marvelous ideas in this field and a lot of them essentially reshaped the world.

Therefore I decided to start writing about what I have learned in a series of posts. This first post is actually a summary of an old paper that I recently read.

Signature schemes are essential to our daily lives. Before computers have existed, we have been signing off papers and documents with our names for a long time. A proper signature simply represents identity and authenticity. Digital Signature is essentially the same idea but in the world of computers. …