video thumbnail 12:33
Cryptography: Crash Course Computer Science #33

2017-10-25

[public] 484K views, 18.2K likes, 203 dislikes audio only

channel thumbCrashCourse

Today we’re going to talk about how to keep information secret, and this isn’t a new goal. From as early as Julius Caesar’s Caesar cipher to Mary, Queen of Scots, encrypted messages to kill Queen Elizabeth in 1587, theres has long been a need to encrypt and decrypt private correspondence. This proved especially critical during World War II as Allan Turing and his team at Bletchley Park attempted to decrypt messages from Nazi Enigma machines, and this need has only grown as more and more information sensitive tasks are completed on our computers. So today, we’re going to walk you through some common encryption techniques such as the Advanced Encryption Standard (AES), Diffie-Hellman Key Exchange, and RSA which are employed to keep your information safe, private, and secure.

Note: In October of 2017, researchers released a viable hack against WPA2, known as KRACK Attack, which uses AES to ensure secure communication between computers and network routers. The problem isn't with AES, which is provably secure, but with the communication protocol between router and computer. In order to set up secure communication, the computer and router have to agree through what's called a "handshake". If this handshake is interrupted in just the right way, an attacker can cause the handshake to fault to an insecure state and reveal critical information which makes the connection insecure. As is often the case with these situations, the problem is with an implementation, not the secure algorithm itself. Our friends over at Computerphile have a great video on the topic: https://www.youtube.com/watch?v=mYtvjijATa4

Produced in collaboration with PBS Digital Studios: http://youtube.com/pbsdigitalstudios

Want to know more about Carrie Anne?

https://about.me/carrieannephilbin

The Latest from PBS Digital Studios: https://www.youtube.com/playlist?list=PL1mtdjDVOoOqJzeaJAV15Tq0tZ1vKj7ZV

Want to find Crash Course elsewhere on the internet?

Facebook - https://www.facebook.com/YouTubeCrash...

Twitter - http://www.twitter.com/TheCrashCourse

Tumblr - http://thecrashcourse.tumblr.com

Support Crash Course on Patreon: http://patreon.com/crashcourse

CC Kids: http://www.youtube.com/crashcoursekids


Crash Course is creating Smarter People | Patreon Support Us!
http://www.patreon.com/crashcourse
DFTBA - CrashCourse We've got merch!
http://store.dftba.com/collections/crashcourse
Introduction
/youtube/video/jhXCTbFnK8o?t=0
Substitution Ciphers
/youtube/video/jhXCTbFnK8o?t=81
Breaking aSubstitution Cipher
/youtube/video/jhXCTbFnK8o?t=108
Permutation Cipher
/youtube/video/jhXCTbFnK8o?t=119
Enigma
/youtube/video/jhXCTbFnK8o?t=153
AES
/youtube/video/jhXCTbFnK8o?t=271
OneWay Functions
/youtube/video/jhXCTbFnK8o?t=427
Modular exponentiation
/youtube/video/jhXCTbFnK8o?t=504
symmetric encryption
/youtube/video/jhXCTbFnK8o?t=616
asymmetric encryption
/youtube/video/jhXCTbFnK8o?t=623
public key encryption
/youtube/video/jhXCTbFnK8o?t=655
CrashCourse At Crash Course, we believe that high-quality educational videos should be available to everyone for free! Subscribe for weekly videos from our current courses! Right now, we're producing Climate & Energy. The Crash Course team has produced more than 45 courses on a wide variety of subjects, including organic chemistry, literature, world history, biology, philosophy, theater, ecology, and many more! We also recently teamed up with Arizona State University to bring you more courses on the Study Hall channel. Help support Crash Course at Patreon.com/CrashCourse.
/youtube/channel/UCX6b17PVsYBQ0ip5gyeme-Q
PBS Voices Produced in association with PBS Digital Studios
youtube.com/channel/UCq6OAftTQOuUBRdtUDq5SUA
Thought Café Art and Animation by Thought Cafe
youtube.com/channel/UCwTZ-JLF5FQ3EmQ2nPaS-lg
Computer Science by CrashCourse
/youtube/video/tpIctyqH29Q