# Lecture 2: Public-key Cryptography

Public-key cryptography
- How does it work?
- Public and private keys
- One-way functions

## Public Key, Cryptography And Oneway Functions

## The Caesar Cipher

## C: Decryption Function

## The Kerckhoff Principle

## Known Plaintext Attack

## How Cryptographic Systems Can Be Broken

## To Prove Who We Are

## An Insecure Channel

## A Symmetric Key

## Tehnician: Private Keys

## Using Public Key Cryptography

## Public And Private Key Pairs

## Asymmetric Key Exchange

## Tehnician: Web Of Trust

## Cryptography And Public Key Cryptography