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<v Speaker 1>Hey there, and welcome back to the deep Dive.

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<v Speaker 2>Glad to be back.

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<v Speaker 1>Today we're diving into network security, the world of cryptography,

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<v Speaker 1>how it works, the history, and what it all means,

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<v Speaker 1>you know for us, right, and we've got some really

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<v Speaker 1>great material to work with. Yeah, we do, including Cryptography

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<v Speaker 1>and Network Security.

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<v Speaker 2>By Berus for Uzan Beruz Florzon.

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<v Speaker 1>That's right. And this book, I gotta say, it doesn't

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<v Speaker 1>just talk about cryptography. It takes us on like a

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<v Speaker 1>journey through its evolution.

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<v Speaker 2>It really does. We're going to see how cryptography has

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<v Speaker 2>developed right alongside technology. Yeah, you're like from basic ciphers

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<v Speaker 2>to the complex systems that protect our digital lives today.

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<v Speaker 1>Yeah.

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<v Speaker 2>And I find really fascinating is that the book uses

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<v Speaker 2>like real world examples to explain even the most complex concepts.

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<v Speaker 1>Yeah.

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<v Speaker 2>It doesn't just you know, throw formulas at you.

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<v Speaker 1>It makes it clear why this stuff matters. Right, And

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<v Speaker 1>speaking of which, it brings up these security goals I

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<v Speaker 1>thought that was interesting early on. Can you break down

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<v Speaker 1>what those actually are?

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<v Speaker 2>Absolutely? Think of it like this, like whenever you send

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<v Speaker 2>an email, make an online purchase, or even store a

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<v Speaker 2>file on your computer, you want to keep that information safe.

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<v Speaker 1>You want to keep it.

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<v Speaker 2>That's where these security goals come in. Confidentiality, integrity, and availability.

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<v Speaker 1>Okay, so confidentiality makes sense keeping things private, but what

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<v Speaker 1>about integrity. Integrity means that my emails are like grammatically correct?

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<v Speaker 1>Is that what it means?

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<v Speaker 2>Not quite? Okay. Integrity is about making sure that information

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<v Speaker 2>hasn't been tampered with. Okay, So think of it like

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<v Speaker 2>a seal on a letter. Okay, if the seal is broken,

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<v Speaker 2>you know that someone might have messed with what's inside, right, Okay.

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<v Speaker 2>So in the digital world, integrity means making sure that

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<v Speaker 2>data hasn't been altered or corrupted during transmission or storage.

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<v Speaker 1>So it's about knowing you're getting the genuine article exactly,

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<v Speaker 1>not some model version exactly. Okay, that's reassuring. And how

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<v Speaker 1>does availability fit into this?

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<v Speaker 2>Availability means ensuring that information is accessible to authorized users

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<v Speaker 2>when they need it.

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<v Speaker 1>I see.

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<v Speaker 2>So imagine like trying to access your bank account but

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<v Speaker 2>the website is down. Yeah, it's a failure of availability.

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<v Speaker 1>I've been there. Not fun. So we have confidentiality to

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<v Speaker 1>keep things private, integrity to make sure nothing's been messed with,

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<v Speaker 1>and availability so we can access what we need when

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<v Speaker 1>we need it exactly. It's like a security trifecta exactly.

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<v Speaker 2>These three goals form like the foundation of network security,

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<v Speaker 2>and they're all interconnected. Okay, but here's where it gets

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<v Speaker 2>really interesting. Achieving these goals is a constant battle because

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<v Speaker 2>they are always those trying to undermine them.

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<v Speaker 1>That's right. The hackers and cyber criminals. Are they the

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<v Speaker 1>ones that we're up against.

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<v Speaker 2>They're certainly part of the equation. But the source material

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<v Speaker 2>takes a broader perspective. Okay, talking attackers in general, and

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<v Speaker 2>it categorizes them into two main types, passive inactive attackers.

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<v Speaker 1>Okay, Passive sounds kind of laid back. Are they the

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<v Speaker 1>ones who like sit back and watch in.

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<v Speaker 2>A way, yes, Passive attackers are more like spies okay,

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<v Speaker 2>So they're trying to gather information without actively changing or

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<v Speaker 2>disrupting anything.

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<v Speaker 1>Okay.

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<v Speaker 2>Think of someone like eavesdropping on a conversation or analyzing

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<v Speaker 2>network traffic to learn about communication patterns.

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<v Speaker 1>Ah Sneaky and active attackers. Those are the ones who

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<v Speaker 1>are actually like breaking into systems exactly.

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<v Speaker 2>They're the ones that are actively trying to modify data,

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<v Speaker 2>disrupt service, or steal information. Yeah, think of hacking into

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<v Speaker 2>a bank account, spreading malware, or launching, you know, a

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<v Speaker 2>denial of service attack to take down a website.

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<v Speaker 1>Oh yeah, so it's like a game of cat and

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<v Speaker 1>mouse with you know, attackers trying to find weaknesses and

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<v Speaker 1>security experts trying to stay one step ahead.

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<v Speaker 2>That's a great analogy, okay. And the history of cryptography

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<v Speaker 2>is like full of examples of this back and forth,

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<v Speaker 2>is constant evolution of techniques to both protect and exploit information.

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<v Speaker 1>Okay, So how do we fight back against these attackers,

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<v Speaker 1>both the passive and the active ones. The book seems

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<v Speaker 1>to suggest that cryptography is, you know, is our secret weapon, right,

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<v Speaker 1>but what exactly is it?

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<v Speaker 2>At its core, cryptography is about using mathematical techniques, okay,

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<v Speaker 2>to transform information in a way that makes it difficult

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<v Speaker 2>to understand without the proper knowledge or tools.

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<v Speaker 1>Okay, yeah, I'm intrigued. And the book mentions these things

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<v Speaker 1>called ciphers, which sound like something out of a spy movie.

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<v Speaker 1>What are those and how do they work?

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<v Speaker 2>So a cipher is essentially a set of rules or

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<v Speaker 2>algorithms for transforming information. They come in various forms, and

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<v Speaker 2>some of the earliest ciphers were surprisingly simple.

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<v Speaker 1>Like those secret decoder rings you get in a cereal box.

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<v Speaker 2>Kind of think of like the classic Caesar cipher, where

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<v Speaker 2>each letter of the alphabet is shifted a fixed number

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<v Speaker 2>of positions.

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<v Speaker 1>Okay, yeah, so if we shifted every letter of three

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<v Speaker 1>positions to the right, A would become D, b would

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<v Speaker 1>become E, and so on exactly.

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<v Speaker 2>So it's a really straightforward method, and it was actually

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<v Speaker 2>used by Julius Caesar himself, wow, to protect military communications.

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<v Speaker 1>So cryptography has been around for a while. Oh yeah,

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<v Speaker 1>but that Caesar cipher sounds pretty basic. Couldn't somebody just

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<v Speaker 1>easily figure it out?

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<v Speaker 2>You're right, the Caesar cipher is very vulnerable, especially if

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<v Speaker 2>you know it's being used. It wouldn't take long to

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<v Speaker 2>crack the code. Yeah, but as cryptographers realize these weaknesses,

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<v Speaker 2>they started developing more complex ciphers, like the Avine cipher.

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<v Speaker 1>Okay, yeah, so the Affine cipher tell me more. What

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<v Speaker 1>makes it different from the Caesar cipher.

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<v Speaker 2>So while the Caesar cipher uses a fixed shift for

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<v Speaker 2>all letters, the Affine cipher introduces a bit more complexity.

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<v Speaker 2>So it uses a combination of multiplication and addition. Okay,

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<v Speaker 2>involving two keys, momultiplicative key and an additive key to

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<v Speaker 2>encrypt each letter.

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<v Speaker 1>Oh. I see, So it's like the Caesar cipher, but

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<v Speaker 1>with like an extra layer of scrambling exactly.

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<v Speaker 2>This makes it more difficult to crack than the Caesar

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<v Speaker 2>cipher because there are more possible key combinations.

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<v Speaker 1>Right.

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<v Speaker 2>However, it's still not.

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<v Speaker 1>Fool proof, so cryptographers had to keep upping their game. Right, Okay,

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<v Speaker 1>what came after the Affine cipher?

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<v Speaker 2>So they realized that relying on a single alphabet for substitution,

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<v Speaker 2>like in both the Caesar and Affine cipher's, right, made

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<v Speaker 2>cipher's vulnerable to attacks based on the frequency of letters

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<v Speaker 2>in a language.

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<v Speaker 1>Oh okay, right.

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<v Speaker 2>So to address this, they developed what are called poly

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<v Speaker 2>alphabetic substitution ciphers.

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<v Speaker 1>Okay.

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<v Speaker 2>These ciphers used multiple substitution alphabets ICEE, making it harder

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<v Speaker 2>to analyze patterns.

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<v Speaker 1>So instead of just one decoder ring, you have a

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<v Speaker 1>whole stack of them.

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<v Speaker 2>It is and one of the most famous poly alphabetic

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<v Speaker 2>ciphers is the Visionaier cipher.

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<v Speaker 1>Okay.

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<v Speaker 2>It uses a keyword to determine which alphabet is used

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<v Speaker 2>for each letter of the plain text.

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<v Speaker 1>Okay, and how does that work? It sounds a little

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<v Speaker 1>more complicated than the Caesar cipher.

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<v Speaker 2>Yeah, so imagine a table with all twenty six possible

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<v Speaker 2>Caesar cipher alpha. That's wrong. The keyword you choose determines

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<v Speaker 2>which row of the table to use for each letter

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<v Speaker 2>of your message.

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<v Speaker 1>Okay.

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<v Speaker 2>So let's say the keyword is secret and the first

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<v Speaker 2>letter of your message is A. You would find the

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<v Speaker 2>row labeled S okay, and then find the column corresponding

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<v Speaker 2>to A, and the letter at the intersection of that

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<v Speaker 2>row and column would be the ciphertext for A.

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<v Speaker 1>Oh I. See so each letter of the keyword dictates

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<v Speaker 1>a different shift for each letter.

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<v Speaker 2>Of the message. Yeah, much harder to crack.

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<v Speaker 1>That sounds much harder to crack.

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<v Speaker 2>It is, Okay. The Visionier cipher was considered unbreakable for centuries.

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<v Speaker 1>Wow.

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<v Speaker 2>But eventually even this cipher was cracked. Cryptographers realized that

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<v Speaker 2>even complex patterns can be exploited. Yeah, with enough cipher

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<v Speaker 2>text and analysis.

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<v Speaker 1>So there's no such thing as an unbreakable code.

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<v Speaker 2>Well, there is one that's considered theoretically unbreakable, the one

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<v Speaker 2>time pad.

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<v Speaker 1>Okay.

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<v Speaker 2>It uses a random key that's as long as the

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<v Speaker 2>message itself and is used only once. But as you

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<v Speaker 2>can imagine, generating, sharing, and protecting these long random keys

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<v Speaker 2>for every single message is incredibly difficult in practice.

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<v Speaker 1>It seems like perfect security often comes with major logistical challenges,

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<v Speaker 1>But it's fascinating to see how cryptographer is constantly innovated,

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<v Speaker 1>pushing the boundaries of what's possible.

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<v Speaker 2>Exactly, And as we move into the digital age, these

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<v Speaker 2>traditional ciphers really pave the way for the even more

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<v Speaker 2>complex and powerful encryption methods we rely on today.

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<v Speaker 1>Which brings us to the modern era of cryptography, where

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<v Speaker 1>things get even more interesting. But before we jump into that,

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<v Speaker 1>let's take a step back, yeah, and explore the mathematical

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<v Speaker 1>foundations that underpin these sophisticated systems. You mentioned earlier that

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<v Speaker 1>cryptography relies on mathematical techniques, right, what are those exactly?

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<v Speaker 2>You're right, the math is crucial, Okay, But it's not

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<v Speaker 2>as complicated as it might sound.

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<v Speaker 1>Okay.

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<v Speaker 2>The book starts with basic concepts like integer arithmetic, focusing

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<v Speaker 2>on division and remainders. It introduces the modulo operator, represented

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<v Speaker 2>by mod which gives you the remainder after a division.

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<v Speaker 1>Okay, I vaguely remember the modulo operator from somewhere, But

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<v Speaker 1>how does it connect to cryptography?

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<v Speaker 2>Well, this simple concept forms the basis for something called

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<v Speaker 2>modular arithmetic, okay, which is a cornerstone of many cryptographic operations.

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<v Speaker 2>It's like doing math on a clock face. Once you

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<v Speaker 2>reach the highest number, you wrap back around to the beginning.

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<v Speaker 1>I see. So if we're working a modula, twelve thirteen

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<v Speaker 1>would be equivalent to one exactly fourteen to two and

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<v Speaker 1>so on.

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<v Speaker 2>Yes, just like how the hours on a clock wrap.

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<v Speaker 1>Around just like a clock.

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<v Speaker 2>Yeah, okay, And this wrapping around behavior is incredibly useful

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<v Speaker 2>for scrambling information I see, in a way that can

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<v Speaker 2>be reversed if you know the key. It's the key

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<v Speaker 2>principle behind many encryption techniques.

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<v Speaker 1>Okay. Interesting, And the book mentions something called congruence right

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<v Speaker 1>in relation to modular arithmetic. What does that mean? So?

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<v Speaker 2>Congruence is a way of saying that two numbers have

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<v Speaker 2>the same remainder when divided by a specific number called

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<v Speaker 2>the modulus.

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<v Speaker 1>Okay.

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<v Speaker 2>The book uses the notation AaB mod n to denote

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<v Speaker 2>that A is congruent to B modulo n.

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<v Speaker 1>Okay. So, for instance, seventeen a two mod five. Yes,

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<v Speaker 1>because both seventeen and two have a remainder of two

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<v Speaker 1>when divided by five.

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<v Speaker 2>Close.

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<v Speaker 1>Actually, it's like they occupy the same spot on our

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<v Speaker 1>clock face of modular five exactly.

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<v Speaker 2>And this concept of congruence is crucial for understanding how

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<v Speaker 2>we can perform operations within these residue classes, which are

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<v Speaker 2>sets of numbers that share the same remainder okay, without

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<v Speaker 2>having to deal with large numbers directly.

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<v Speaker 1>So it's like we're creating these shortcuts, these equivalence classes,

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<v Speaker 1>right that let us work with smaller, more manageable numbers exactly.

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<v Speaker 2>And these concepts lay the groundwork for even more complex

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<v Speaker 2>tools and cry potography, like those used to find multiplicative

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<v Speaker 2>inverses and solve equations within modular arithmetic, which we can

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<v Speaker 2>explore further later. But for now, let's take a look

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<v Speaker 2>at another powerful mathematical tool used in cryptography. Okay, matrices.

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<v Speaker 1>Matrices, those bring back memories of high school math. I'm

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<v Speaker 1>not sure how they relate to encrypting information, right.

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<v Speaker 2>They might seem unrelated, but matrices offer a way to

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<v Speaker 2>manipulate blocks of data rather than individual numbers. They are

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<v Speaker 2>essential for modern ciphers that operate on larger chunks of data.

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<v Speaker 2>Remember those block ciphers we talked about earlier. Yeah, matrices

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<v Speaker 2>are key to how they work.

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<v Speaker 1>Okay, so instead of shifting individual letters, we're now shifting

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<v Speaker 1>and transforming entire blocks of data using matrices exactly. Okay,

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<v Speaker 1>that sounds pretty powerful.

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<v Speaker 2>It is, And just like with numbers, we can perform

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<v Speaker 2>operations on matrices addition, subtraction, multiplication, even finding their inverses.

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<v Speaker 2>The book explains how these operations are crucial for designing

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<v Speaker 2>and analyzing complex encryption algorithms.

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<v Speaker 1>So it's like we're taking all these basic building blocks

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<v Speaker 1>modular arithmetic, congruence matrices and using them to create sophisticated

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<v Speaker 1>encryption machines.

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<v Speaker 2>You're getting it. Yeah, And the book dives into even

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<v Speaker 2>more specialized concepts like residue matrices, which are matrices whose

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<v Speaker 2>elements are calculated using modulo operations. It's like combining the

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<v Speaker 2>power of matrices with the cyclical nature of modular arithmetic.

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<v Speaker 1>This is all starting to come together. It's amazing to

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<v Speaker 1>see how these like seemingly abstract mathematical concepts can be

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<v Speaker 1>harnessed to create these incredibly powerful and secure encryption methods.

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<v Speaker 2>Absolutely. Yeah, And the best part is that we're just

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<v Speaker 2>getting started. The source material goes even deeper, exploring how

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<v Speaker 2>these concepts are applied to solve equations and create the

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<v Speaker 2>building blocks for modern cryptographic systems.

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<v Speaker 1>Well, I'm already hooked. It's like we're unraveling the secrets

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<v Speaker 1>of a hidden world.

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<v Speaker 2>We are, and as we delve further into the world

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<v Speaker 2>of modern cryptography, you'll see how these mathematical foundations pave

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<v Speaker 2>the way for some truly remarkable innovations.

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<v Speaker 1>I'm excited. Okay, my brain is buzzing with all this

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<v Speaker 1>mathematical groundwork we've laye I'm ready to see how it

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<v Speaker 1>all comes together in the real world of modern cryptography.

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<v Speaker 2>Okay, So the book takes us on a journey through

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<v Speaker 2>the evolution of modern ciphers, starting with a closer look

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<v Speaker 2>at symmetric key ciphers. These are ciphers where both the

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<v Speaker 2>sender and receiver use the same key for encryption and decryption,

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<v Speaker 2>like sharing a secret code.

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<v Speaker 1>Right. We talked about those earlier, like the Caesar cipher

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<v Speaker 1>and the Visioneer cipher, but those seem pretty vulnerable once

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<v Speaker 1>people figure out how they work. How do modern ciphers

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<v Speaker 1>improve on these older methods.

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<v Speaker 2>That's a great question. Yeah, one of the key principles

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<v Speaker 2>of modern cryptography is something called Kirkhoff's principle, and this

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<v Speaker 2>principle states that the security of a cryptosystem should rely

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<v Speaker 2>on this secrecy of the key, not the secrecy of

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<v Speaker 2>the algorithm itself.

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<v Speaker 1>So even if someone knows the general method of encryption,

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<v Speaker 1>they can't break the code unless they have the key exactly.

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<v Speaker 1>That sounds pretty revolutionary.

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<v Speaker 2>It was a game changer. It meant that cryptographers could

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<v Speaker 2>focus on developing strong, publicly known algorithms rather than trying

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<v Speaker 2>to keep the methods themselves secret.

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<v Speaker 1>I see this.

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<v Speaker 2>Led to more robust and thoroughly tested encryption techniques.

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<v Speaker 1>That makes sense. It's like having a strong lock on

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<v Speaker 1>your door. Even if people know the general design of

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<v Speaker 1>the lock, they can't open it without the key. But

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<v Speaker 1>I imagine that even with strong algorithms, there are still

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<v Speaker 1>ways that attackers can try and break the code.

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<v Speaker 2>Absolutely. The book dies into various types of attacks, starting

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<v Speaker 2>with the classic brute force attack, and this is where

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<v Speaker 2>the attacker simply tries every possible key combination until they

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<v Speaker 2>find the one that decrypts the message.

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<v Speaker 1>So it's like trying every combination on a lock until

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<v Speaker 1>you find the one that opens it exactly.

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<v Speaker 2>It's not tedious, it is, and it can take a

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<v Speaker 2>very very long time, especially if the key is long.

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<v Speaker 2>But with the advancement of computing power, proot force attacks

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<v Speaker 2>became more feasible. So this led to the development of

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<v Speaker 2>ciphers with longer keys to make those attacks less effective.

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<v Speaker 1>So it's a constant arms race. Yes, as computers get faster,

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<v Speaker 1>the keys need to get longer exactly.

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<v Speaker 2>But brute force isn't the only way to attack a cipher, right.

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<v Speaker 2>There are also more subtle methods, like statistical attacks that

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<v Speaker 2>exploit the patterns and frequencies of letters in a language.

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<v Speaker 2>We touched on this earlier with the Caesar cipher. If

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<v Speaker 2>you know that E is the most common letter in English,

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<v Speaker 2>you can start to use that information to guess the key, right.

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<v Speaker 1>I remember that, So even if you have a strong algorithm,

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<v Speaker 1>if it doesn't properly mask the natural patterns of language,

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<v Speaker 1>an attacker might still be able to figure it out.

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<v Speaker 2>That's right. And they are even more advanced techniques like

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<v Speaker 2>chosen plaintext attacks, where the attacker actually gets to choose

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<v Speaker 2>specific plaintext to be encrypted okay, and observe the resulting ciphertext.

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<v Speaker 2>I see by carefully crafting their inputs, they can try

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<v Speaker 2>to deduce information about the key or the cipher's workings.

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<v Speaker 1>That sounds devious. It's like a scientist running experiments to

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<v Speaker 1>figure out how a black box works. So how do

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<v Speaker 1>modern cipher's protect against these kinds of attacks?

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<v Speaker 2>Modern ciphers are designed with these attack vectors in mind. Okay,

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<v Speaker 2>they employ principles like diffusion and confusion to make it

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<v Speaker 2>incredibly difficult for attackers to exploit patterns or gain any

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<v Speaker 2>useful information, even if they can choose the plaintext.

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<v Speaker 1>Okay, diffusion and confusion tell me more about those they

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<v Speaker 1>sound They sound intriguing.

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<v Speaker 2>Yeah, Diffusion, as the book explains, aims to spread the

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<v Speaker 2>influence of each bit of the plaintext throughout the cipher text. Okay,

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<v Speaker 2>that way, changing even one bit in the plaintext will

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<v Speaker 2>result in a completely different ciphertext.

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<v Speaker 1>Oh wow.

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<v Speaker 2>This makes it hard for attackers to isolate and analyze

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<v Speaker 2>individual parts of the message.

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<v Speaker 1>So it's like scrambling an egg so thoroughly that even

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<v Speaker 1>if you change a tiny bit of the yoke, the

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<v Speaker 1>whole thing looks completely different.

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<v Speaker 2>That's a great analogy. And then we have confusion, which

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<v Speaker 2>makes the relationship between the ciphertext and the key as

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<v Speaker 2>complex and unpredictable as possible.

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<v Speaker 1>Okay.

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<v Speaker 2>This prevents attackers from deducing the key even if they

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<v Speaker 2>have some knowledge about the plaintext or the ciphertext.

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<v Speaker 1>It's like a magician's trick where even if you know

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<v Speaker 1>the outcome, you can't figure out the method exactly.

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<v Speaker 2>And these principles are put into practice through a combination

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<v Speaker 2>of different techniques okay. For instance, modern cizers often use

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<v Speaker 2>what are called substitution permutation networks okay, which involve multiple

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<v Speaker 2>rounds of substitutions and permutations to scramble the data thoroughly.

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<v Speaker 1>So it's like taking those basic operations that we talked

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<v Speaker 1>about earlier, modular arithmetic matrix operations, combining them in intricate

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<v Speaker 1>ways to create a powerful encryption engine.

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<v Speaker 2>Precisely. And one of the most well known structures for

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<v Speaker 2>building block ciphers is the feistyal cipher structure.

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<v Speaker 1>The feistal cipher. I've heard that name before, Yeah, tell

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<v Speaker 1>me more about what makes it special.

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<v Speaker 2>So the feistyal cipher divides the plaintext block into two

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<v Speaker 2>halves okay, and applies a series of rounds where one

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<v Speaker 2>half is used to modify the other, okay, and then

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<v Speaker 2>they're swapped. I see this process of splitting, modifying, and

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<v Speaker 2>swapping is repeated multiple times, making the relationship between the

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<v Speaker 2>plaintext and the ciphertext incredibly complex.

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<v Speaker 1>It's like a dance where the two halves of the

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<v Speaker 1>data constantly interacting and changing partners.

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<v Speaker 2>I love that analogy, okay. And one of the elegant

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<v Speaker 2>aspects of the Feystal structure is that encryption and decryption

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<v Speaker 2>are very similar processes, just performed in reverse. Oh okay,

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<v Speaker 2>this makes it efficient for implementation.

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<v Speaker 1>So it's like using the same steps to shuffle and

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<v Speaker 1>then unshuffle a deck of cards exactly. But even with

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<v Speaker 1>all these intricate techniques, are modern cipher is truly unbreakable?

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<v Speaker 2>Well, no cipher is truly unbreakable in the absolute sense. However,

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<v Speaker 2>modern cephers, especially those used in widely adopted standards, have

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<v Speaker 2>been rigorously analyzed and tested by cryptographers worldwide.

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<v Speaker 1>So it's about making it so computationally expensive and time

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<v Speaker 1>consuming to break the code that it's basically impossible.

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<v Speaker 2>Exactly. And the source material dives into the specifics of

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<v Speaker 2>some of these widely used ciphers, starting with the Data

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<v Speaker 2>Encryption Standard or DESDES.

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<v Speaker 1>I've heard of that one, ye, wasn't it like the

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<v Speaker 1>gold standard for encryption for a long time?

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<v Speaker 2>It was. DES was adopted in the nineteen seventies, okay,

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<v Speaker 2>and was widely used for several decades. It's a sixty

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<v Speaker 2>four bit block cipher based on the Feistal structure, and

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<v Speaker 2>it uses the fifty six bit key.

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<v Speaker 1>Okay, that's a lot of bits.

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<v Speaker 2>Yeah, But I've also heard the DEES eventually became vulnerable.

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<v Speaker 2>What happened?

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<v Speaker 1>Yeah, what happened?

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<v Speaker 2>You're right? As computing power advanced DES is fifty six

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<v Speaker 2>bit key became susceptible to brute force attacks.

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<v Speaker 1>I see.

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<v Speaker 2>So while it was considered secure for many years, it

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<v Speaker 2>eventually needed an upgrade.

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<v Speaker 1>Okay. So what replaced DES To.

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<v Speaker 2>Address the limitations of DES, Triple DES or three DES

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<v Speaker 2>was introduced, and it essentially applies the DES algorithm three

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<v Speaker 2>times in a row with different keys, significantly increasing the

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<v Speaker 2>effective key length.

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<v Speaker 1>So it's like adding extra layers of security right to

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<v Speaker 1>the DES involved exactly.

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<v Speaker 2>But even with three DES, the search for a more

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<v Speaker 2>robust and efficient encryption standard continued.

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00:20:41.400 --> 00:20:44.359
<v Speaker 1>Okay, right, So, and that search led to the development

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<v Speaker 1>of the Advanced.

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<v Speaker 2>Encryption Standard or AES, which is the current gold standard

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<v Speaker 2>for symmetric key encryption.

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<v Speaker 1>AES have definitely heard of that one. It seems to

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<v Speaker 1>be everywhere these days. What makes it so special?

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<v Speaker 2>So AES is a more modern block cipher okay that

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<v Speaker 2>was designed to replace des okay. It supports various key

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<v Speaker 2>lengths one hundred and twenty, eight hundred ninety two, and

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<v Speaker 2>two hundred and fifty six bits, making it much more

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<v Speaker 2>resistant to boot force attacks. Plus, it's incredibly efficient and

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<v Speaker 2>can be implemented in both hardware and.

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<v Speaker 1>Software, so it's fast, strong, and adaptable. No wonder it's

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<v Speaker 1>so widely used. Exactly, But the book doesn't just talk

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<v Speaker 1>about block ceurfers, right. We also touched on stream ciphers earlier.

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<v Speaker 1>How have those evolved in the modern era?

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<v Speaker 2>You're right. The book returns to stream ciphers, highlighting their

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<v Speaker 2>advantages and applications where data is processed one bit or

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<v Speaker 2>byte at a time by streaming media or real time communication.

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<v Speaker 2>Modern stream ciphers use sophisticated techniques to generate pseudorandom key

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<v Speaker 2>streams that are combined with the plaintext, so.

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<v Speaker 1>It's like a continuous flow of encryption adapting to the

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<v Speaker 1>data stream in real time exactly. But we talked earlier

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<v Speaker 1>about how important it is for the keystream to be

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<v Speaker 1>truly random. How do modern stream ciphers ensure that.

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<v Speaker 2>They use components called feedback shift registers or fsrs. Okay,

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00:22:06.599 --> 00:22:09.799
<v Speaker 2>and these are essentially electronic circuits that can generate sequences

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<v Speaker 2>of bits based on certain mathematical principles.

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<v Speaker 1>Hold on fsrs. I feel like we've come full circle.

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<v Speaker 1>Don't we talk about those you did when we were

431
00:22:16.960 --> 00:22:20.279
<v Speaker 1>discussing you have a great memory, linear diophantinic creations.

432
00:22:20.519 --> 00:22:25.480
<v Speaker 2>Yes, Okay, The mathematical principles behind generating those pseudorandom sequences

433
00:22:25.519 --> 00:22:30.240
<v Speaker 2>in fsrs do indeed tie back to those concepts from

434
00:22:30.359 --> 00:22:32.960
<v Speaker 2>number theory and modular arithmetic we discussed earlier.

435
00:22:33.079 --> 00:22:36.480
<v Speaker 1>Wow, it's amazing to see how all these pieces connect. Yeah,

436
00:22:36.519 --> 00:22:40.079
<v Speaker 1>it's like cryptography is built on this foundation of interconnected

437
00:22:40.119 --> 00:22:41.359
<v Speaker 1>mathematical ideas.

438
00:22:41.400 --> 00:22:44.960
<v Speaker 2>It truly is, and that foundation supports an even wider

439
00:22:45.079 --> 00:22:49.960
<v Speaker 2>array of techniques and applications like hashing and digital signatures, Yeah,

440
00:22:50.000 --> 00:22:52.519
<v Speaker 2>which play a crucial role in modern network security.

441
00:22:52.599 --> 00:22:55.799
<v Speaker 1>Okay, hashing and digital signatures, those are terms that I've

442
00:22:55.839 --> 00:22:59.000
<v Speaker 1>definitely heard before, but I'm not sure I fully understand

443
00:22:59.039 --> 00:23:01.960
<v Speaker 1>what they are or how they work. Can you shed

444
00:23:02.000 --> 00:23:02.640
<v Speaker 1>some light on those?

445
00:23:02.799 --> 00:23:07.200
<v Speaker 2>Absolutely? The book provides a great overview of these essential concepts.

446
00:23:07.279 --> 00:23:08.119
<v Speaker 2>Let's start with hashing.

447
00:23:08.279 --> 00:23:08.640
<v Speaker 1>Okay.

448
00:23:08.880 --> 00:23:11.000
<v Speaker 2>Think of a hash function as a special kind of

449
00:23:11.359 --> 00:23:14.359
<v Speaker 2>like digital fingerprint machine. Okay, You've eed it any data,

450
00:23:14.400 --> 00:23:17.240
<v Speaker 2>no matter how large, and it spits out a unique,

451
00:23:17.440 --> 00:23:20.440
<v Speaker 2>fixed size string of characters called a hash value.

452
00:23:20.559 --> 00:23:24.359
<v Speaker 1>So it's like taking a massive encyclopedia and condensing it

453
00:23:24.440 --> 00:23:26.519
<v Speaker 1>into a single unique code.

454
00:23:26.640 --> 00:23:28.279
<v Speaker 2>That's a great way to put it, okay, And what

455
00:23:28.359 --> 00:23:32.599
<v Speaker 2>makes hash function so powerful is that they're deterministic. The

456
00:23:32.680 --> 00:23:37.200
<v Speaker 2>same input always produces the same output. Plus they're designed

457
00:23:37.240 --> 00:23:42.480
<v Speaker 2>to be what we call collision resistant, meaning it's extremely

458
00:23:42.559 --> 00:23:46.480
<v Speaker 2>difficult to find two different inputs that produce the same

459
00:23:46.519 --> 00:23:47.200
<v Speaker 2>hash value.

460
00:23:47.359 --> 00:23:50.200
<v Speaker 1>Oh okay, So if I download a file from the

461
00:23:50.240 --> 00:23:53.359
<v Speaker 1>Internet and I calculate its hash value, I can compare

462
00:23:53.400 --> 00:23:56.119
<v Speaker 1>it to the hash value provided by the source exactly,

463
00:23:56.160 --> 00:23:58.200
<v Speaker 1>and if they match, I can be confident that the

464
00:23:58.200 --> 00:24:00.200
<v Speaker 1>file hasn't been tampered with exactly.

465
00:24:00.279 --> 00:24:03.759
<v Speaker 2>That's one of the main uses of hashing, verifying data integrity.

466
00:24:04.200 --> 00:24:07.119
<v Speaker 2>It's like having a tamper proof seal on a document. Okay,

467
00:24:07.200 --> 00:24:10.559
<v Speaker 2>any changes to the document, even the slightest alteration, will

468
00:24:10.559 --> 00:24:12.599
<v Speaker 2>result in a completely different hash value.

469
00:24:12.799 --> 00:24:15.240
<v Speaker 1>That's incredibly useful. Yeah, it makes me feel a lot

470
00:24:15.279 --> 00:24:19.160
<v Speaker 1>more secure about downloading, you know, software, important files. But

471
00:24:19.240 --> 00:24:22.920
<v Speaker 1>what about digital signatures? How do they fit into the picture.

472
00:24:23.599 --> 00:24:27.759
<v Speaker 2>So, digital signatures are like electronic fingerprints that guarantee the

473
00:24:27.799 --> 00:24:31.480
<v Speaker 2>authenticity and integrity of a message or a document. They

474
00:24:31.519 --> 00:24:36.400
<v Speaker 2>combine hashing with public key cryptography Okay, which we haven't

475
00:24:36.400 --> 00:24:38.519
<v Speaker 2>dealt into yet, So it's like a.

476
00:24:38.559 --> 00:24:42.880
<v Speaker 1>Two factor authentication for messages. The hash verifies the content

477
00:24:42.960 --> 00:24:46.079
<v Speaker 1>hasn't been altered, and then the public key magic confirms

478
00:24:46.079 --> 00:24:46.680
<v Speaker 1>who it's from.

479
00:24:46.920 --> 00:24:49.599
<v Speaker 2>You got it. Yeah, and public key cryptography is a

480
00:24:49.640 --> 00:24:54.039
<v Speaker 2>whole other, like fascinating area of modern cryptography and it

481
00:24:54.039 --> 00:24:57.240
<v Speaker 2>plays a crucial role in securing communication on the Internet.

482
00:24:57.319 --> 00:25:00.519
<v Speaker 1>Okay, you've definitely peaked my curiosity. Yeah, let's die into that.

483
00:25:00.440 --> 00:25:05.000
<v Speaker 2>Next, happy to Public key cryptography is truly revolutionary and

484
00:25:05.039 --> 00:25:08.720
<v Speaker 2>it like underpins many of the security measures that we

485
00:25:08.799 --> 00:25:10.119
<v Speaker 2>rely on in our digital lives.

486
00:25:10.160 --> 00:25:12.759
<v Speaker 1>Okay, you mentioned public key cryptography, right, I feel like

487
00:25:12.799 --> 00:25:15.720
<v Speaker 1>we're about to enter a whole new level of encryption

488
00:25:15.920 --> 00:25:16.920
<v Speaker 1>wizardry here.

489
00:25:17.240 --> 00:25:21.799
<v Speaker 2>You're not wrong. Public key cryptography, or asymmetric cryptography, was

490
00:25:21.839 --> 00:25:24.880
<v Speaker 2>a major breakthrough in the history of cryptography. Okay, it's

491
00:25:24.960 --> 00:25:28.200
<v Speaker 2>bit mind bending at first, but once you grasp the concept,

492
00:25:28.759 --> 00:25:30.119
<v Speaker 2>it's incredibly elegant.

493
00:25:30.240 --> 00:25:31.960
<v Speaker 1>Well, I'm all ears, lay it on me.

494
00:25:32.119 --> 00:25:37.240
<v Speaker 2>So the book explains that unlike symmetric key cryptography, where

495
00:25:37.359 --> 00:25:41.440
<v Speaker 2>both the sender and receiver use the same key, public

496
00:25:41.519 --> 00:25:45.359
<v Speaker 2>key cryptography uses a pair of keys, a public key

497
00:25:45.680 --> 00:25:46.519
<v Speaker 2>and a private key.

498
00:25:47.279 --> 00:25:50.160
<v Speaker 1>Okay, two keys instead of one. How does that work? Exactly?

499
00:25:50.200 --> 00:25:52.519
<v Speaker 2>So the public key can be given to anyone okay,

500
00:25:52.599 --> 00:25:56.200
<v Speaker 2>while the private key is kept secret. What's amazing is

501
00:25:56.240 --> 00:25:58.640
<v Speaker 2>that anything encrypted with the public key can only be

502
00:25:58.720 --> 00:26:00.839
<v Speaker 2>decrypted with the correspond private key.

503
00:26:00.960 --> 00:26:04.039
<v Speaker 1>So it's like having a special mailbox with two locks. Okay,

504
00:26:04.279 --> 00:26:06.960
<v Speaker 1>anyone can drop a letter in using the public key,

505
00:26:07.440 --> 00:26:09.880
<v Speaker 1>but only the person with the private key can open

506
00:26:09.920 --> 00:26:11.440
<v Speaker 1>the mailbox and read the letters.

507
00:26:11.559 --> 00:26:14.960
<v Speaker 2>That's a perfect analogy, okay, And this system solves a

508
00:26:15.039 --> 00:26:19.160
<v Speaker 2>major challenge of symmetric key cryptography, the key distribution problem.

509
00:26:19.240 --> 00:26:21.720
<v Speaker 1>Right. We talked earlier about how difficult it is to

510
00:26:21.759 --> 00:26:25.480
<v Speaker 1>securely share a single secret key especially in a world

511
00:26:25.519 --> 00:26:29.640
<v Speaker 1>with millions of interconnected devices. But with public key cryptography,

512
00:26:29.960 --> 00:26:33.319
<v Speaker 1>you don't need to share that secret key in advance, exactly.

513
00:26:33.400 --> 00:26:36.480
<v Speaker 2>You can freely distribute your public key and anyone can

514
00:26:36.559 --> 00:26:38.960
<v Speaker 2>use it to encrypt a message that only you with

515
00:26:39.079 --> 00:26:40.480
<v Speaker 2>your private key can decrypt.

516
00:26:40.839 --> 00:26:43.400
<v Speaker 1>That's brilliant. It seems like a much more practical solution

517
00:26:43.559 --> 00:26:46.839
<v Speaker 1>for secure communication, especially in the digital age. Yeah, but

518
00:26:46.880 --> 00:26:48.839
<v Speaker 1>how do we know that the public key we're using

519
00:26:49.160 --> 00:26:51.240
<v Speaker 1>actually belongs to the person we think.

520
00:26:51.039 --> 00:26:54.839
<v Speaker 2>It does, right, That's a great question. That's where digital

521
00:26:54.839 --> 00:26:58.240
<v Speaker 2>certificates and public key infrastructure or PKI come in.

522
00:26:58.440 --> 00:26:58.799
<v Speaker 1>Okay.

523
00:26:59.079 --> 00:27:03.039
<v Speaker 2>A digital certific it is essentially a digital document that

524
00:27:03.240 --> 00:27:07.799
<v Speaker 2>binds a public key to a specific entity like a person, organization,

525
00:27:07.960 --> 00:27:08.480
<v Speaker 2>or website.

526
00:27:08.559 --> 00:27:10.640
<v Speaker 1>So it's like a digital passport for a public.

527
00:27:10.480 --> 00:27:12.640
<v Speaker 2>Key exactly, okay, vouching for its.

528
00:27:12.480 --> 00:27:14.960
<v Speaker 1>Authenticity, vouching for its authenticity, okay.

529
00:27:15.400 --> 00:27:19.680
<v Speaker 2>And these certificates are issued by trusted entities called certificate

530
00:27:19.720 --> 00:27:21.519
<v Speaker 2>authorities or CAAs.

531
00:27:21.720 --> 00:27:22.079
<v Speaker 1>Okay.

532
00:27:22.160 --> 00:27:26.119
<v Speaker 2>They verify the identity of the keyholder before issuing the certificate.

533
00:27:26.240 --> 00:27:28.440
<v Speaker 1>Okay. So it's like a system of trust, right, we

534
00:27:28.480 --> 00:27:32.680
<v Speaker 1>trust the CAAs to verify identities and issue legitimate certificate,

535
00:27:33.119 --> 00:27:35.920
<v Speaker 1>and then we can trust that the public keys associated

536
00:27:35.920 --> 00:27:38.200
<v Speaker 1>with those certificates are genuine precisely.

537
00:27:38.519 --> 00:27:42.359
<v Speaker 2>PKI is a complex system, but it's this foundation of

538
00:27:42.440 --> 00:27:46.039
<v Speaker 2>trust that allows us to use public key cryptography for

539
00:27:46.160 --> 00:27:47.759
<v Speaker 2>secure communication online.

540
00:27:48.000 --> 00:27:50.839
<v Speaker 1>It's incredible to think that something as fundamental as trust

541
00:27:51.039 --> 00:27:53.880
<v Speaker 1>underpins so much of our digital security.

542
00:27:54.119 --> 00:27:55.079
<v Speaker 2>Yeah, it really is.

543
00:27:55.400 --> 00:27:59.400
<v Speaker 1>But how is public key cryptography actually used in practice?

544
00:27:59.599 --> 00:28:02.000
<v Speaker 1>Can you give me some real world examples?

545
00:28:02.160 --> 00:28:05.160
<v Speaker 2>Absolutely. One of the most common applications is securing websites

546
00:28:05.240 --> 00:28:08.599
<v Speaker 2>using SSLTLS, which we briefly touched on earlier. When you

547
00:28:08.599 --> 00:28:11.799
<v Speaker 2>see that little padlock icon in your browser's address bar,

548
00:28:12.319 --> 00:28:14.799
<v Speaker 2>it means that the communication between your browser and the

549
00:28:14.799 --> 00:28:18.319
<v Speaker 2>website is encrypted using SSLTLS.

550
00:28:18.480 --> 00:28:21.000
<v Speaker 1>Right. I always look for that padlock, especially when I'm

551
00:28:21.119 --> 00:28:24.079
<v Speaker 1>entering sensitive information like credit card details, but I never

552
00:28:24.119 --> 00:28:26.000
<v Speaker 1>really understood what was happening behind the scenes.

553
00:28:26.200 --> 00:28:31.640
<v Speaker 2>So SSLTLS uses a combination of symmetric and public key cryptography. Initially,

554
00:28:31.880 --> 00:28:35.039
<v Speaker 2>public key cryptography is used to establish a secure connection

555
00:28:35.480 --> 00:28:38.839
<v Speaker 2>and exchange a session key, which is a temporary symmetric

556
00:28:38.960 --> 00:28:41.000
<v Speaker 2>key used for the rest of the communication.

557
00:28:41.440 --> 00:28:45.079
<v Speaker 1>So it's like using the public key to securely agree

558
00:28:45.119 --> 00:28:49.599
<v Speaker 1>on a secret handshake, right that only the two parties involved, no, right,

559
00:28:49.640 --> 00:28:51.759
<v Speaker 1>and then they use that secret handshake for the rest

560
00:28:51.759 --> 00:28:52.480
<v Speaker 1>of the conversation.

561
00:28:52.680 --> 00:28:56.119
<v Speaker 2>Exactly. This way you get the benefits of both types

562
00:28:56.160 --> 00:28:59.720
<v Speaker 2>of cryptography, the security of public key cryptography for the

563
00:29:00.279 --> 00:29:04.000
<v Speaker 2>key exchange, okay, and the efficiency of symmetric key cryptography

564
00:29:04.200 --> 00:29:05.599
<v Speaker 2>for the ongoing communication.

565
00:29:06.279 --> 00:29:09.759
<v Speaker 1>That's a clever combination, it is. But SSLTLS isn't the

566
00:29:09.759 --> 00:29:13.279
<v Speaker 1>only application of public key cryptography, is it not at all.

567
00:29:13.559 --> 00:29:15.920
<v Speaker 2>It's also used for things like digital signatures, which we

568
00:29:15.960 --> 00:29:19.960
<v Speaker 2>talked about earlier. A digital signature uses the sender's private

569
00:29:20.039 --> 00:29:22.559
<v Speaker 2>key to encrypt a hash of the message.

570
00:29:22.640 --> 00:29:22.960
<v Speaker 1>Okay.

571
00:29:23.200 --> 00:29:25.680
<v Speaker 2>The recipient can then use the sender's public key to

572
00:29:25.759 --> 00:29:28.519
<v Speaker 2>decrypt the hash and compare to a hash they calculate

573
00:29:28.559 --> 00:29:31.839
<v Speaker 2>themselves Okay. If the hash is match, it verifies both

574
00:29:31.880 --> 00:29:34.480
<v Speaker 2>the sender's identity and the messages integrity.

575
00:29:34.720 --> 00:29:37.400
<v Speaker 1>So it's like a tamper proof seal that also confirms

576
00:29:37.440 --> 00:29:41.119
<v Speaker 1>the sender's identity exactly. That's crucial for things like online

577
00:29:41.160 --> 00:29:44.000
<v Speaker 1>banking and electronic document signing, right exactly.

578
00:29:44.319 --> 00:29:48.440
<v Speaker 2>Digital signatures are used in countless applications where authenticity and

579
00:29:48.480 --> 00:29:50.079
<v Speaker 2>integrity are paramount.

580
00:29:50.279 --> 00:29:53.119
<v Speaker 1>This is all so fascinating. It's amazing to see how

581
00:29:53.119 --> 00:29:57.000
<v Speaker 1>cryptography has evolved to meet the challenges of the digital age,

582
00:29:57.359 --> 00:30:00.920
<v Speaker 1>from securing communication to verify identities.

583
00:30:01.119 --> 00:30:01.759
<v Speaker 2>Who really is?

584
00:30:01.880 --> 00:30:05.680
<v Speaker 1>Okay, so we've talked about securing data in transit, but

585
00:30:05.759 --> 00:30:10.400
<v Speaker 1>the book also mentions protecting data at rest. Yes, you know,

586
00:30:10.599 --> 00:30:13.720
<v Speaker 1>the information that's stored on our devices and servers. How

587
00:30:13.759 --> 00:30:15.839
<v Speaker 1>do we keep that information safe?

588
00:30:16.039 --> 00:30:19.799
<v Speaker 2>That's a crucial aspect of network security. The source material

589
00:30:19.880 --> 00:30:22.759
<v Speaker 2>discusses techniques like disc encryption and file encryption.

590
00:30:22.960 --> 00:30:23.279
<v Speaker 1>Okay.

591
00:30:23.400 --> 00:30:26.519
<v Speaker 2>These methods use strong encryption algorithms to scramble the data

592
00:30:26.559 --> 00:30:30.079
<v Speaker 2>on a storage drive or within specific files, so making

593
00:30:30.079 --> 00:30:32.400
<v Speaker 2>it unreadable about the proper decryption key.

594
00:30:32.559 --> 00:30:35.160
<v Speaker 1>So even if someone steals my laptop or hacks into

595
00:30:35.160 --> 00:30:38.119
<v Speaker 1>a server, the data is still protected. It's like having

596
00:30:38.160 --> 00:30:42.119
<v Speaker 1>a digital safe for my sensitive information exactly.

597
00:30:42.440 --> 00:30:45.519
<v Speaker 2>And these techniques are becoming increasingly important as we store

598
00:30:45.559 --> 00:30:47.240
<v Speaker 2>more and more of our lives online.

599
00:30:47.319 --> 00:30:50.759
<v Speaker 1>It's like we're building a fortress around our data, using

600
00:30:50.920 --> 00:30:54.599
<v Speaker 1>multiple layers of cryptographic techniques to keep it safe from

601
00:30:54.640 --> 00:30:56.519
<v Speaker 1>prying eyes and malicious actors.

602
00:30:57.039 --> 00:30:58.960
<v Speaker 2>That's a great way to put it and It's not

603
00:30:59.079 --> 00:31:03.359
<v Speaker 2>just about the technical measures. It's also about being aware

604
00:31:03.400 --> 00:31:06.920
<v Speaker 2>of the risks and practicing good security hygiene right.

605
00:31:07.119 --> 00:31:11.839
<v Speaker 1>Things like choosing strong passwords, being cautious about phishing attacks exactly,

606
00:31:11.920 --> 00:31:14.359
<v Speaker 1>and keeping our software up to date are all part

607
00:31:14.400 --> 00:31:15.000
<v Speaker 1>of the equation.

608
00:31:15.240 --> 00:31:18.559
<v Speaker 2>Absolutely, security is a shared responsibility and we all have

609
00:31:18.599 --> 00:31:20.960
<v Speaker 2>a role to play in protecting ourselves and our data.

610
00:31:21.039 --> 00:31:24.039
<v Speaker 1>This has been an incredible journey. We've covered so much ground,

611
00:31:24.079 --> 00:31:27.519
<v Speaker 1>from the history of cryptography and the mathematical concepts that

612
00:31:27.640 --> 00:31:31.599
<v Speaker 1>underpin it to the sophisticated systems that secure our digital world.

613
00:31:32.039 --> 00:31:34.279
<v Speaker 1>It's mind blowing to see how it all comes together.

614
00:31:34.480 --> 00:31:37.359
<v Speaker 2>It has been a pleasure exploring all these concepts with you. Yeah,

615
00:31:37.440 --> 00:31:41.319
<v Speaker 2>and remember, crytography is a constantly evolving field. As technology

616
00:31:41.359 --> 00:31:45.440
<v Speaker 2>advances and new threats emerge, the landscape of network security

617
00:31:45.480 --> 00:31:46.720
<v Speaker 2>will continue to change.

618
00:31:47.000 --> 00:31:50.039
<v Speaker 1>So what does the future hold for cryptography? Any hints

619
00:31:50.079 --> 00:31:50.599
<v Speaker 1>from the book?

620
00:31:50.920 --> 00:31:55.839
<v Speaker 2>The book touches on some fascinating emerging trends, particularly the

621
00:31:55.880 --> 00:31:58.039
<v Speaker 2>potential impact of quantum computing.

622
00:31:58.640 --> 00:32:03.119
<v Speaker 1>Quantum computing we heard it could revolutionize many fields, but

623
00:32:03.160 --> 00:32:06.200
<v Speaker 1>I didn't realize it had implications for cryptography as well.

624
00:32:06.400 --> 00:32:09.640
<v Speaker 2>It's a game changer. Quantum computers have the potential to

625
00:32:09.720 --> 00:32:13.200
<v Speaker 2>break many of the encryption algorithms we rely on today.

626
00:32:13.359 --> 00:32:15.359
<v Speaker 1>That sounds a bit alarming. Are we on the verge

627
00:32:15.400 --> 00:32:17.160
<v Speaker 1>of a cryptographic apocalypse?

628
00:32:17.480 --> 00:32:21.119
<v Speaker 2>Not quite. Cryptographers are already working hard to develop new

629
00:32:21.160 --> 00:32:24.480
<v Speaker 2>algorithms that are resistant to quantum attacks, Okay, ensuring that

630
00:32:24.519 --> 00:32:27.279
<v Speaker 2>our data remains secure even in a post quantum world.

631
00:32:27.400 --> 00:32:30.000
<v Speaker 1>That's reassuring. It's like a whole new era of cryptographic

632
00:32:30.039 --> 00:32:31.839
<v Speaker 1>innovation is on the horizon exactly.

633
00:32:31.920 --> 00:32:34.720
<v Speaker 2>And the knowledge you've gained from this deep dive gives

634
00:32:34.720 --> 00:32:37.599
<v Speaker 2>you a great foundation for understanding these future developments.

635
00:32:37.680 --> 00:32:39.640
<v Speaker 1>It certainly has. I feel like I've gone from being

636
00:32:39.680 --> 00:32:43.680
<v Speaker 1>a cryptography novice to having a real appreciation for the

637
00:32:43.720 --> 00:32:45.559
<v Speaker 1>complexity and importance of this field.

638
00:32:45.839 --> 00:32:48.880
<v Speaker 2>That's the goal. Yeah, Knowledge is power, and by understanding

639
00:32:48.920 --> 00:32:52.000
<v Speaker 2>these concepts, you're better equipped to make informed decisions about

640
00:32:52.000 --> 00:32:53.319
<v Speaker 2>your own digital security.

641
00:32:53.640 --> 00:32:56.480
<v Speaker 1>Absolutely, And on that note, we've reached the end of

642
00:32:56.480 --> 00:32:59.759
<v Speaker 1>our cryptographic adventure for today. Thanks for joining us on

643
00:32:59.799 --> 00:33:02.279
<v Speaker 1>this deep dive into the world of secret ciphers and

644
00:33:02.319 --> 00:33:06.759
<v Speaker 1>the fascinating realm of network security. Until next time, stay curious,

645
00:33:06.920 --> 00:33:08.519
<v Speaker 1>stay informed, and stay secure.