00:04

now out of the asymmetric algorithms we've just talked about. There are three that I think are worth an additional follow up, a little bit more discussion, and the first of those is R S. A.

00:15

And it's named after its creators, rivals Shamir and Edelman and Ron ride this very, very big in the crypt. A world, as are the other gentleman, but right, it's just one of the better known

00:25

Ah, a couple of testable things. First of all, this is currently the standard for digital signatures. So when we talk about a digital signature, if you'll recall, the document gets hashed. *** hashing that piece is done by hashing algorithm like MD five or shot one. We'll talk about those in just a minute.

00:44

But once the hash is complete,

00:46

then there's another algorithm that's necessary to encrypt the hash with the centre's private key. That's what our essay does. So Rs a meets or satisfies the digital signature standard for today. So our essay is what you're using when you digitally sign a document, at least for the asymmetric piece, the second

01:06

of buzz word about our essays that it uses factory ization

01:11

is based on the idea that it's very easy

01:17

to do well. Let let me let me back up and say Our essay sometimes refer to as a trapdoor function as well, and it uses factories ation for that trap door. What that means is it's math that's very easy to perform one way and very difficult to reverse.

01:33

So, for instance, if I give everyone calculators very easy to take two large prime numbers and multiply them together,

01:41

however, if you just see the result, figuring out what prime numbers were multiplied to give us that result is very, very difficult, right, so it's easy to multiply. But to look at the product that result and see what was then figure out what was multiplied to get that product very complex. And that's the trap door of our essay.

02:00

So use this factory ization,

02:02

and it's the current standard for digital signatures.

02:06

Now defeat Helmand! Diffie Hellman is hugely significant because this was the first asymmetric algorithm. Diffie Hellman does nothing but key Agreement is my check. The phrase for Diffie Hellman is secure key agreement without pre shared secrets. So

02:24

Diffie Hellman is kind of based on the idea

02:28

that in an asymmetric environment I have two keys. You have two keys, publican fraud. You have to public or to one public, one product.

02:40

my keys. I know my public in my private key that I'd also know of your public. So out of the total of four I know three of four thousands.

02:50

You also would know three out of the four values, even though what you know is different than what I know.

02:55

Having this knowledge Diffie Hellman the idea is we can agree upon 1/5 number

03:01

based on the shared information that we have. It's really pretty cool. And as a matter of fact, there is a little work sheet that if you ever get bored, man, this is something fund ring out at a party or around a campfire. It's the Diffie Hellman key agreement work sheet, but ultimately

03:21

based on the type of math

03:23

that if you know and I know

03:24

three out of four values, we can agree upon 1/5 number, and we'll actually do one of the side very sessions on the defeat. Hellman key agreement is pretty cool to see how that works, but you don't need any of the math. Um, just know that it is fascinating and fabulous math.

03:42

Diffie Hellman is all about secure key agreement without

03:47

Now the third asymmetric algorithm worth mentioning is E. C C. Elliptical curve grip cryptography.

03:57

The thing that they generally like to test about for E. C. C. Is that it's a very efficient algorithm, and it is used on devices with limited processing capability. So you know you're talking about

04:12

these horrified the chips that need to encrypt or older handheld devices, the P D. A's and cellphones of years gone by because it is so fast and so efficient. E. C. C. Was a good choice. It only works in very specific environments, but it was designed

04:29

for the purpose of devices processing power. So those three out of all the asymmetric algorithms, all six that we looked at, those would be the ones I would focus in on