Secret Key Exchange (Diffie-Hellman) - Computerphile

How do we exchange a secret key in the clear? Spoiler: We don't - Dr Mike Pound shows us exactly what happens.

This video was filmed and edited by Sean Riley.

[OscarAlsing]

Poor Alice and Bob. Always exposed. Always out there. Never left alone. ❤️

[denisr]

The analogy with colors in this video is pure genius! Thank you guys, this was an amazing introduction to Diffie-Hellman!

[ScottPlude]

5 years later and this is still done a million times a minute out there. Very well explained, thank you!

[RobertMilesAI]

Nice! This is a subject I should have covered immediately after the Public Key Cryptography video, since that one lays out the problem of exchanging keys that Diffie-Hellman solves. Great to see such a clear explanation, I doubt I'd have gone to the effort to get coloured liquids!

[CGoody]

Watched the defcon presentation from years ago given by the creator of the diffie-helman key exchange... It was absolutely fascinating. Dude is an innovator and pure genius. Seems like a nice guy as well

[goshisanniichi]

Random squirting of fluids... exactly what I wanted to see this early in the morning...

[frenchify]

I really like this guy. Been watching and rewatching his lessons for like 3 hours.

[nO_dNAL]

What I like most about this channel is the ability of the presenters to explain things simply without mathematics. That is real teaching, not reciting formal proofs and equations

[dmatuzo]

How curious, PBS Infinite Series have been talking about encription in the last few days. Now I've got double the encryption bonanza! This has been a good week.

[CristiNeagu]

1:04 First rule of cryptography: Unless your job is to create cryptographic algorithms, *never* implement your own cryptographic algorithms. You *will* screw it up.

[ennis_w]

Everytime I feel confused by e2ee or key exchange, I will come back and see these videos. Really helps.

[ironman]

I'm a simple man. I see a computerphile video with Mike Pound, I click like

[kingbran]

Sir, you have sincerely helped me with my homework far more than my textbook ever could. Thank you so much for making these videos! :D

[StuffOffYouStuff]

Fantasticly simple and easy to understand explanation, thank you for this.
I'm studying for the Sec+, so basics atm. But i've been getting very confused by some of the terms around encryption. I'm going to ask a completely naive question. I understand to encrypt there are two components, 1) the algorithm, 2) the key. I've seen Diffie-Hellman described as a) a public key encryption algorithm, b) a key exchange protocol, c) a public-key encryption protocol.
RSA is also described as an asymmetric public key encryption algorithm.
Diffie-Hellman only generates keys, it does not provide an algorithm for use with those keys to then encrypt data
RSA also generates keys, but can also encrypt/decrypt data
So, my questions/assertions:
1) Is there general misuse of the term "encryption algorithm" or just "encrpytion" as to what that encompasses? What should it encompass?
2) My current feeling is, Encryption = 1) the algorithm, 2) the key (but not the key generation). Encryption algorithm = 1) literally just the algorithm, not the key. EErr, i don't know what term to use that would also encompass the key generation bit. So yeah confused still.
2) The process of Diffie-Hellman key generation/exchange is still considered an encryption algorithm because it outputs data (the shared public) that makes deciphering the input to create it practically impossible?
3) Diffie-Hellman is considered asymmetric because it generates a private/public key pair first?
4) Diffie-Hellman can also be used to generate asymmetric keys ONLY?
5) So the private symmetric keys Diffie-Hellman creates would form the symmetric keys for one of the symmetric encryption algorithms like RC4/AES?
4) Looking back at the above then, the term encryption looks like it should actually include the discrete phase of key generation/distribution?

[qfytidw]

One thing I liked about Hellman was that not only did he invent a clever way to distribute private keys he also invented a decent tasting mayonnaise with an enormous shelf life.

It has been forecast that a jar or mayonnaise will still be more or less OK even after being stored at refrigerator temperatures for five thousand years.

If the Ancient Egyptians had known about Hellman's mayonnaise recipe and had stored a few sealed jars in the pyramids we'd still be able to open them and make a decent tuna mayo sandwich.

Probably long after the nuclear apocalypse we'll be eating Hellman's Mayonnaise probably with roach meat. Or maybe the roaches will win and eat Human Mayo sandwiches.

[Laurabeck]

This demonstration was a classic Parker square.

[daviaquino]

I am writing Javascript decryption libraries for Apple Pay, Google Pay and Shopify and came across this video trying to learn more about the theory. Fantastic!

[realprathap]

I studied Diffie-Hellman in college from a textbook, but after a few years, I forgot it because I shifted to a different field. And now I am watching this YouTube videos random, and my reaction, Wooow, yeah, that makes sense now!
😯

[lumanaughty]

This might be the quarantine talking, but I’m starting to get a crush on this dude

[dasjucktmichnicht]

i love the style of the whole channel! proofs nobody really needs power point or laborious anmations.