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Intro to Modern Cryptography

10 videos
2 talkthroughs
A new problem emerges in the 20th century. What happens if Alice and Bob can never meet to share a key in the first place?

The fundamental theorem of arithmetic

Independent realization from an ancestor's perspective

Public key cryptography: What is it?

Why do we need public key cryptography?

The discrete logarithm problem

A mathematical lock using modular arithmetic

Diffie-hellman key exchange

Walkthrough of Diffie-Hellman Key Exchange

RSA encryption: Step 1

Introduction to why we would need RSA

RSA encryption: Step 2

Setting up a trapdoor one-way function

RSA encryption: Step 3

RSA Encryption (step 3)

Time Complexity (Exploration)

Time complexity animation

Euler's totient function

Measuring the divisibility of a number

Euler Totient Exploration

How to measure the breakability of a number?

RSA encryption: Step 4

RSA worked example

What should we learn next?

Help decide what's next! What do you want to learn?