mirror of
https://github.com/jackyzha0/quartz.git
synced 2025-12-25 05:44:06 -06:00
25 lines
535 B
Markdown
25 lines
535 B
Markdown
---
|
|
title: "passwords"
|
|
aliases:
|
|
tags:
|
|
- comp210
|
|
---
|
|
|
|
# Passwords
|
|
- not good
|
|
- lots of bad advice
|
|
- we are lazy
|
|
- "safe" passwords are difficult to enter on touch screen devices
|
|
- to many accouts
|
|
|
|
## entropy
|
|
- amount of randomness
|
|
- measure of the number of guesse an attacker would need to brute foarce
|
|
- $E = log_2(A^L)$
|
|
- A = size of alphabet
|
|
- L = length of password
|
|
- E = entropy in bits
|
|
- 80 bits is "safe"
|
|
- would take decades
|
|
- 6 digits passoword - 29 bits (took 4 seconds to brute force)
|
|
- + uppercase and numbers - 36 bits |