Security Fundamentals

Photo by John Salvino on Unsplash

What is security?

Photo by Emily Morter on Unsplash

A state of being free from threat or danger

Definition of "security" by Lexico.com

https://www.lexico.com/definition/security

Photo by freestocks on Unsplash

The state of being protected against the criminal or unauthorized use of electronic data, or the measures taken to achieve this.

Definition of "cybersecurity" by Lexico.com

https://www.lexico.com/definition/cybersecurity

Photo by Taskin Ashiq on Unsplash

It's all about your data

Photo by Joshua Sortino on Unsplash

Once it's gone, it's lost

Photo by Marko Blažević on Unsplash

How do you protect your data

Photo by N I F T Y A R T ✍🏻 on Unsplash

Who can you trust?

Photo by Simon Moog on Unsplash

You close the door and authenticate

Photo by Tim Mossholder on Unsplash

1. Something you know

2. Something you have

3. Something you are

Photo by Glenn Carstens-Peters on Unsplash

Step 1

Passwords

Photo by Matthew Brodeur on Unsplash

Passwords are keys

Photo by Shane Avery on Unsplash

Each site or service has a lock

Photo by Rob King on Unsplash

When you get
more locks...

Photo by marcos mayer on Unsplash

...you need more keys

Photo by Samantha Lam on Unsplash

And it never ends...

Photo by Samantha Lam on Unsplash

...ever...

Photo by Chunlea Ju on Unsplash

How many passwords have you memorised?

Photo by Edwin Andrade on Unsplash

How many times have you used the same password?

Photo by Carlos Arthur M.R on Unsplash

List of the 18 most common passwords in 2019 according to the NCSC
https://www.ncsc.gov.uk/news/most-hacked-passwords-revealed-as-uk-cyber-survey-exposes-gaps-in-online-security

Photo by O12 on Unsplash

Humans vs Machines

Photo by Chris Liverani on Unsplash

Speed of calculation

Photo by Charles Deluvio on Unsplash

Correctness of action

Photo by Jon Tyson on Unsplash

Capacity of memory

Photo by Franck V. on Unsplash

Brute-force

Photo by Gaelle Marcel on Unsplash

1. 'a', 'b', 'c'...
2. 'aa', 'ab', 'ac'...
3. 'aaaaaaaa', 'aaaaaaab'...

Photo by Sandy Millar on Unsplash

1. Try all words alone
2. Try all combinations of 2 words
3. Try all combinations of N words

Photo by Michał Parzuchowski on Unsplash

1. Try the most common passwords
2. Try the most common words
3. Try the most common variants

What makes a
good password?

Photo by Moja Msanii on Unsplash

Photo by Mathew Schwartz on Unsplash

1. How many different symbols? :: n
2. How many symbols in total? :: L

Photo by Antoine Dautry on Unsplash

Number of combinations

L

n

Photo by Alvaro Reyes on Unsplash

• Letters, digits, and 10 symbols :: n = 72
• Easy to memorize :: L = 10
• Combinations: 3.74 x 10^18
• 2-core CPU @ 2.0 GHz: 2 days

Photo by Jeremy Thomas on Unsplash

• Lowercase letters only :: n = 26
• Very long :: L = 50
• Combinations: 5.61 x 10^70
• 2-core CPU @ 2.0 GHz: 1.62 x 10^56 days

Size matters more

How to make
good password?

Photo by Sven Mieke on Unsplash

Photo by Ashim D’Silva on Unsplash

Make it random

Photo by REVOLT on Unsplash

Humans memorise stupid shit easily

Photo by Aaron Burden on Unsplash

Make it unique

How do you memorise all those passwords?

Photo by Aarón Blanco Tejedor on Unsplash

Photo by Marija Zaric on Unsplash

You don't

Meet LastPass

Photo by Rick Mason on Unsplash

A randomly generated password for each service

Memorise a single password to unlock them all

Photo by Sebastian Herrmann on Unsplash

Your life in two passwords:

• E-mail
• Password manager

What if this fails?

Photo by Dan Meyers on Unsplash

Two-factor authentication

Photo by Charles Deluvio on Unsplash

1. Login with password
2. Prove you have a device with you

What if even this fails?

Photo by Daniel Tausis on Unsplash

Encrypt anything

Photo by Markus Spiske on Unsplash