# Lecture 8: Pseudorandom Number Generators (PRNGs) and Diffie-Hellman Key Exchange

- Notes
- Sp20 Slides
- Playlist (length: 31:08)

## PRNGs: Definition

## HMAC-DRBG and PRNG Applications

## Stream Ciphers

## PRGs

(True/False) A block cipher is a type of PRG

## Discrete Logarithm

(True/False) Given g^x (mod p) and p, it is difficult to find x even when given additional knowledge of g

## Diffie-Hellman Key Exchange

Why can't Alice and Bob simply send their keys a/b to eachother in order to compute the shared g^(ab)?

## Diffie-Hellman Key Exchange Security

When Malice performs the MiTM attack, she must pick the same g^m (mod p) that she sends to both parties

## Detecting Pairing MiTM attacks

Why don't we always use this method of entering a digest of the derived key to check that the same key was derived?