Hi! I'm the author. Happy to answer questions.
Crypto 101 – Introductory course on cryptography
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Re: Crypto 101 – Introductory course on cryptography
#12I read the book, it is well written, accessible and pretty accurate. I think it's worth a skim even just to learn more about something you vaguely know but you can't explain in your own words.
I'm glad you feel that way, because I'm honestly embarrassed by how shoddy my old writing is. (I'm the author.)
Re: Crypto 101 – Introductory course on cryptography
#13Started reading it, pretty good so far! Only thing, why did you choose to introduce block cipher modes in the stream cipher chapter? This makes little sense to me.
Because the book tries to produce a narrative where new features are introduced out of obvious necessity: in this case, encrypting more than a block. And you can do that with modes of operations or "native" stream ciphers. Essentially I'm handwaving and pretending that e.g. AESCTR is just a stream cipher :-)
Re: Crypto 101 – Introductory course on cryptography
#14Started reading it, pretty good so far! Only thing, why did you choose to introduce block cipher modes in the stream cipher chapter? This makes little sense to me.
It actually makes a lot of sense for practical purposes. This probably looks strange to you because most introductory cryptography texts strictly segregate stream and block ciphers. The standard pedagogical style bifurcates modern symmetric encryption into one of these two categories and talks about things like synchronization, on-the-fly encryption, speed, error correction, etc. between the two.
In point of fact, there isn't as significant a difference between the two in active research and industry. Many (most?) stream ciphers actually use blocks internally. For example, Salsa (and its spiritual successor, ChaCha) both use blocks and rounds. From one legitimate perspective, a block cipher mode enabling streaming encryption is a generalization of a stream cipher.
When you develop a stream cipher without a block system internally[1], you're trying to remove the versatility of block cipher modes in exchange for (hopefully significant) improvements in speed and efficiency. This is very difficult to do while maintaining security. At the end of the day there are only so many ways to do confusion and diffusion.
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1. For example see Sosemanuk, which internally uses a linear feedback shift register and finite state machine.
Re: Crypto 101 – Introductory course on cryptography
#15superficial stuff
Re: Crypto 101 – Introductory course on cryptography
#16superficial stuff
What would you have preferred to see that wouldn't make it "superficial"?
Re: Crypto 101 – Introductory course on cryptography
#17Re: Crypto 101 – Introductory course on cryptography
#18Oh interesting. I recently got "Applied Cryptography" in one of the nostarchpress sales. I expected it to be turbo technical and way outside my league but popped it open on a whim one day. So far it's incredibly accessible, does anyone have thoughts on that versus this course? Worth taking the course after I finish Applied cryptography?
Re: Crypto 101 – Introductory course on cryptography
#19Earlier quoted context omitted.
What would you have preferred to see that wouldn't make it "superficial"?
AES explanation before DES? Why? It doesn't make any sense.
... because the only way to introduce ciphers is, what, chronologically? Why? And why does that make it superficial?
Re: Crypto 101 – Introductory course on cryptography
#20Oh interesting. I recently got "Applied Cryptography" in one of the nostarchpress sales. I expected it to be turbo technical and way outside my league but popped it open on a whim one day. So far it's incredibly accessible, does anyone have thoughts on that versus this course? Worth taking the course after I finish Applied cryptography?
Do you mean "Serious Cryptography"? Applied Cryptography isn't a No Starch Press book.