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Can anyone recommend any good content to learn cryptography? Like, even if I read the algorithm for AES I have zero understanding about why it works this way I

Can anyone recommend any good content to learn cryptography? Like, even if I read the algorithm for AES I have zero understanding about why it works this way I've finished the Cryptography I on Coursera already. Can't recommend it enough

pet_the_bird 5mo ago
"Cryptography Made Simple" By Nigel Smart and "A Graduate Course in Applied Cryptography" by Dan Boneh and Victor Shoup are excellent resources for people that have affinity with Math and CS. The second resource can be a tough read, and I would strongly recommend not skipping the first few chapters.
cumshitpiss 5mo ago
https://cs.ru.nl/~joan/papers/JDA_VRI_Rijndael_2002.pdf https://cs.ru.nl/~joan/papers/JDA_VRI_Rijndael_2002.pdf A large part of this book is aimed at the readers who want to know why we designed Rijndael in the way we did. For them, we explain the ideas and principles underlying the design of Rijndael, culminating in our wide trail design strategy.
coldstartops 5mo ago
I've been through Introduction to Modern Cryptography by Katz and Lindell. Can recommend, as it starts with Caesars cipher, one time pads, and builds towards modern cryptography.
yason 5mo ago
Back in the day, I read Applied Cryptography (by Schneier) and clarity rained upon many things.
- tptacek 5mo ago
  More damage has been done by that book than by any Herbert Schildt C language book.
  - esafak 5mo ago
    This is news to me. Is it him in general or just that book?
    - tptacek 5mo ago
      Just that book. The followup (Practical Cryptography, now called Cryptography Engineering, though it's the same book) is much, much better --- though it's also totally out of date at this point, and would also get you in trouble.
  - LPisGood 5mo ago
    Can you elaborate?
    - tptacek 5mo ago
      It's a book that is much more interested in presenting an almanac-esque survey of everything that was happening in cryptography at the time it was written (also unhelpful: it was written at a particularly un-rigorous point in the evolution of cryptography) than it is in teaching readers how to accomplish anything safely.
  - krupan 5mo ago
    It's honestly been a long time since I've encountered this attitude around cryptography, where not even Schneier can be trusted and you have no hope of actually understanding cryptography so don't even try (yes, I'm referring to your math comments too). Welcome back! For those feeling like this guy is being a dick, that's a normal reaction, but try to understand that this attitude was cultivated and used by enlightened individuals back when many people thought they were making secure software without even salting and hashing their users passwords. People thought md5 was good enough, https was barely being used, people had to be convinced to use ssh instead of telnet and ftp, and so forth. Drilling the idea into people that cryptography and security is difficult and that you should listen to experts had to be done. Don't take it personally. So yes, as you study cryptography, do keep in mind that it's extremely unlikely that you'll learn enough to come up with something better on your own, that you will very likely make mistakes if you try to write your own implementation of any cryptographic algorithms, and that you should still just use existing libraries and the recommendations of experts on best practices.
zOneLetter 5mo ago
I looked at the recommendations under your comment, but I don't think I'm capable of these either lol Any recommendations for a technically competent person, but for someone with math knowledge trailing off at Calc 2?
- krupan 5mo ago
  The math isn't that difficult once you grok mod math. It's like time, like doing addition and subtraction on a clock. What's 10 + 4 on a clock? 4 hours past 10 is 2.
  - tptacek 5mo ago
    The math stays difficult after basic discrete concepts and gets more difficult as you go. :) It's straightforward to get yourself to a place where you can do cryptographic things and feel somewhat comfortable with what's happening. Truly understanding it to the point where you can reason safely about it is deceptively harder.
    - mswphd 5mo ago
      yeah I generally would say that learning about the actual schemes (tends to be) doable by a casual enthusiast, but learning about how the SOTA attacks work (which motivate scheme design for sure) is much more difficult.
  - gucci-on-fleek 5mo ago
    Hmm, I've studied a lot of math, and I disagree. Cryptography is mostly number theory, which always looks simple on the surface, and often only needs "elementary" tools, but I still find it much harder than other areas of math. For example, the proof that there are infinitely many primes looks simple [0], but it's still pretty hard to understand, let alone derive yourself independently. And the other important cryptography/number theory theorems like Euler's totient theorem [1] are even trickier. [0]: https://en.wikipedia.org/wiki/Euclid%27s_theorem https://en.wikipedia.org/wiki/Euclid%27s_theorem [1]: https://en.wikipedia.org/wiki/Euler%27s_theorem https://en.wikipedia.org/wiki/Euler%27s_theorem
rramadass 5mo ago
1) Understanding Cryptography by Christof Paar et al. I learnt cryptography from the 1st edition. Its very practical and highly recommended - https://www.cryptography-textbook.com/ https://www.cryptography-textbook.com/ 2) Cryptography: Theory and Practice by Douglas Stinson et al. This is a more mathematical treatment and hence a nice complement to the Paar book above - https://www.routledge.com/Cryptography-Theory-and-Practice/Stinson-Paterson/p/book/9781032476049 https://www.routledge.com/Cryptography-Theory-and-Practice/S... 3) For understanding how cryptography is used in Networks see the classic Network Security: Private Communication in a Public World by Radia Perlman et al. The 2nd edition is where i started my journey into network security/cryptography needed for my then job. Highly recommended - https://www.amazon.com/Network-Security-Charlie-Kaufman/dp/0136643604 https://www.amazon.com/Network-Security-Charlie-Kaufman/dp/0... The first two books give you the "mechanisms" (and theory) of cryptography i.e. the building blocks. The last book puts everything together to implement "policies" via practical applications (eg. IPSec/SSL etc.) for the real world. They are complementary and hence should be studied together to get the full picture.
PaulStatezny 5mo ago
I would highly recommend the free book Crypto 101. https://www.crypto101.io https://www.crypto101.io
soupspaces 5mo ago
[dead]
philangist 5mo ago
https://mit6875.github.io/ https://mit6875.github.io/ - MIT's Foundations of Cryptography is publicly available with full lectures, lecture note pdfs, and 5 problem sets. It's very rigorous and proof-driven which can be hard at times, but the professor's enthusiasm for the subject is infectious and makes the lectures a pleasure to watch.

pet_the_bird 5mo ago

"Cryptography Made Simple" By Nigel Smart and "A Graduate Course in Applied Cryptography" by Dan Boneh and Victor Shoup are excellent resources for people that have affinity with Math and CS. The second resource can be a tough read, and I would strongly recommend not skipping the first few chapters.

cumshitpiss 5mo ago

https://cs.ru.nl/~joan/papers/JDA_VRI_Rijndael_2002.pdf https://cs.ru.nl/~joan/papers/JDA_VRI_Rijndael_2002.pdf A large part of this book is aimed at the readers who want to know why we designed Rijndael in the way we did. For them, we explain the ideas and principles underlying the design of Rijndael, culminating in our wide trail design strategy.

coldstartops 5mo ago

I've been through Introduction to Modern Cryptography by Katz and Lindell. Can recommend, as it starts with Caesars cipher, one time pads, and builds towards modern cryptography.

yason 5mo ago

Back in the day, I read Applied Cryptography (by Schneier) and clarity rained upon many things.

tptacek 5mo ago
More damage has been done by that book than by any Herbert Schildt C language book.
- esafak 5mo ago
  This is news to me. Is it him in general or just that book?
  - tptacek 5mo ago
    Just that book. The followup (Practical Cryptography, now called Cryptography Engineering, though it's the same book) is much, much better --- though it's also totally out of date at this point, and would also get you in trouble.
- LPisGood 5mo ago
  Can you elaborate?
  - tptacek 5mo ago
    It's a book that is much more interested in presenting an almanac-esque survey of everything that was happening in cryptography at the time it was written (also unhelpful: it was written at a particularly un-rigorous point in the evolution of cryptography) than it is in teaching readers how to accomplish anything safely.
- krupan 5mo ago
  It's honestly been a long time since I've encountered this attitude around cryptography, where not even Schneier can be trusted and you have no hope of actually understanding cryptography so don't even try (yes, I'm referring to your math comments too). Welcome back! For those feeling like this guy is being a dick, that's a normal reaction, but try to understand that this attitude was cultivated and used by enlightened individuals back when many people thought they were making secure software without even salting and hashing their users passwords. People thought md5 was good enough, https was barely being used, people had to be convinced to use ssh instead of telnet and ftp, and so forth. Drilling the idea into people that cryptography and security is difficult and that you should listen to experts had to be done. Don't take it personally. So yes, as you study cryptography, do keep in mind that it's extremely unlikely that you'll learn enough to come up with something better on your own, that you will very likely make mistakes if you try to write your own implementation of any cryptographic algorithms, and that you should still just use existing libraries and the recommendations of experts on best practices.

zOneLetter 5mo ago

I looked at the recommendations under your comment, but I don't think I'm capable of these either lol Any recommendations for a technically competent person, but for someone with math knowledge trailing off at Calc 2?

krupan 5mo ago
The math isn't that difficult once you grok mod math. It's like time, like doing addition and subtraction on a clock. What's 10 + 4 on a clock? 4 hours past 10 is 2.
- tptacek 5mo ago
  The math stays difficult after basic discrete concepts and gets more difficult as you go. :) It's straightforward to get yourself to a place where you can do cryptographic things and feel somewhat comfortable with what's happening. Truly understanding it to the point where you can reason safely about it is deceptively harder.
  - mswphd 5mo ago
    yeah I generally would say that learning about the actual schemes (tends to be) doable by a casual enthusiast, but learning about how the SOTA attacks work (which motivate scheme design for sure) is much more difficult.
- gucci-on-fleek 5mo ago
  Hmm, I've studied a lot of math, and I disagree. Cryptography is mostly number theory, which always looks simple on the surface, and often only needs "elementary" tools, but I still find it much harder than other areas of math. For example, the proof that there are infinitely many primes looks simple [0], but it's still pretty hard to understand, let alone derive yourself independently. And the other important cryptography/number theory theorems like Euler's totient theorem [1] are even trickier. [0]: https://en.wikipedia.org/wiki/Euclid%27s_theorem https://en.wikipedia.org/wiki/Euclid%27s_theorem [1]: https://en.wikipedia.org/wiki/Euler%27s_theorem https://en.wikipedia.org/wiki/Euler%27s_theorem

rramadass 5mo ago

1) Understanding Cryptography by Christof Paar et al. I learnt cryptography from the 1st edition. Its very practical and highly recommended - https://www.cryptography-textbook.com/ https://www.cryptography-textbook.com/ 2) Cryptography: Theory and Practice by Douglas Stinson et al. This is a more mathematical treatment and hence a nice complement to the Paar book above - https://www.routledge.com/Cryptography-Theory-and-Practice/Stinson-Paterson/p/book/9781032476049 https://www.routledge.com/Cryptography-Theory-and-Practice/S... 3) For understanding how cryptography is used in Networks see the classic Network Security: Private Communication in a Public World by Radia Perlman et al. The 2nd edition is where i started my journey into network security/cryptography needed for my then job. Highly recommended - https://www.amazon.com/Network-Security-Charlie-Kaufman/dp/0136643604 https://www.amazon.com/Network-Security-Charlie-Kaufman/dp/0... The first two books give you the "mechanisms" (and theory) of cryptography i.e. the building blocks. The last book puts everything together to implement "policies" via practical applications (eg. IPSec/SSL etc.) for the real world. They are complementary and hence should be studied together to get the full picture.

PaulStatezny 5mo ago

I would highly recommend the free book Crypto 101. https://www.crypto101.io https://www.crypto101.io

soupspaces 5mo ago

[dead]

philangist 5mo ago

https://mit6875.github.io/ https://mit6875.github.io/ - MIT's Foundations of Cryptography is publicly available with full lectures, lecture note pdfs, and 5 problem sets. It's very rigorous and proof-driven which can be hard at times, but the professor's enthusiasm for the subject is infectious and makes the lectures a pleasure to watch.