7 ms·

Handbook of Applied Cryptography (2001)

114 points by rfreytag 10y ago

silenteh 10y ago
If you are looking for a free book about applied cryptography, in my opinion this is the best you can find: https://crypto.stanford.edu/~dabo/cryptobook/ https://crypto.stanford.edu/~dabo/cryptobook/
- user2994cb 10y ago
  And Dan Boneh's Coursera course is excellent too (maybe one day he will get around to doing the endlessly postponed part 2).
canistr 10y ago
Anyone have any thoughts on Communication System Security (https://www.crcpress.com/Communication-System-Security/Chen-Gong/9781439840368 https://www.crcpress.com/Communication-System-Security/Chen-...)? I learned quite a bit from this book in undergrad which is also written by a UW professor (Guang Gong).
JoachimSchipper 10y ago
This is old cryptography. This book should not be quite as bad for its readers as Schneier's Applied Cryptography (which includes many ciphers which were known to be broken at the time, with little hint of that fact in the text), but it's still old-fashioned. E.g. - Chapter 7 "block ciphers" doesn't even mention CTR mode, but does mention CFB and OFB. Modern cryptosystems all use CTR mode, and no new system I'm aware of uses CFB or OFB. - Chapter 8 "Public-Key Encryption" doesn't even mention elliptic-curve cryptography, despite almost all new cryptosystems being based on that in some form or another. This chapter also doesn't appear to mention RSA padding, which is crucial to a secure RSA implementation. - Chapter 9 "Hash Functions and Data Integrity" doesn't mention anything newer than SHA-1. But SHA-1 is thoroughly deprecated, and will be broken in the next few years. Just buy a new book instead; I hear good things about Cryptography Engineering, and I liked "An Introduction to Modern Cryptography" (more mathematical, less engineering-focused).
- pieter_mj 10y ago
  > But SHA-1 is thoroughly deprecated, and will be broken in the next few years. Why is this a problem? sha1 is not broken by design, it's only broken by current and future computing power.
  - taejo 10y ago
    No, SHA-1's design is broken. The attacks still need a lot of computing power, but much less than they would if SHA-1 was secure.
  - geofft 10y ago
    That's not true. SHA-1 is a 160-bit hash, which means that you'd expect it to take on average 2^80 hash computations to find a collision. The best attacks against full SHA-1 require more like 2^57 to 2^61 computations, and there are attacks against parts of SHA-1 that require quite a bit less than that (which indicates that the design is risky). https://en.wikipedia.org/wiki/SHA-1#Cryptanalysis_and_validation https://en.wikipedia.org/wiki/SHA-1#Cryptanalysis_and_valida... The difference between 2^60 and 2^80 is huge. If 2^80 operations take, say, a thousand years, it would take only about 8 hours to do 2^60 operations. (Also, there's the additional twist that SHA-1 isn't even the fastest known algorithm. If you switch to BLAKE2, you can get faster hashing, and the output is 256-bit, so the brute-force strength is 2^128, which more than makes up for each individual operation being a little faster. https://blake2.net/ https://blake2.net/)
- geofft 10y ago
  Another free and more up-to-date option is http://www.crypto101.io/ http://www.crypto101.io/ , but significant parts of the book are still in progress.
- egjerlow 10y ago
  What about the updated Cryptography engineering book by Schneier et al? Do you have any experience with it?
  - nabla9 10y ago
j2kun 10y ago
Some chapters in this book (e.g. Chapter 4) contain very useful knowledge about practical algorithms for working with the underlying mathematical objects used as cryptographic primitives. Some that I found particularly useful in studying elliptic curve cryptography was the section on irreducible polynomials over finite fields.
curiousgal 10y ago
2001? Call an appeal to authority but I'll wait and see what tptacek has to say about this.

114 points by rfreytag 10y ago

If you are looking for a free book about applied cryptography, in my opinion this is the best you can find: https://crypto.stanford.edu/~dabo/cryptobook/ https://crypto.stanford.edu/~dabo/cryptobook/

user2994cb 10y ago
And Dan Boneh's Coursera course is excellent too (maybe one day he will get around to doing the endlessly postponed part 2).

canistr 10y ago

Anyone have any thoughts on Communication System Security (https://www.crcpress.com/Communication-System-Security/Chen-Gong/9781439840368 https://www.crcpress.com/Communication-System-Security/Chen-...)? I learned quite a bit from this book in undergrad which is also written by a UW professor (Guang Gong).

JoachimSchipper 10y ago

This is old cryptography. This book should not be quite as bad for its readers as Schneier's Applied Cryptography (which includes many ciphers which were known to be broken at the time, with little hint of that fact in the text), but it's still old-fashioned. E.g. - Chapter 7 "block ciphers" doesn't even mention CTR mode, but does mention CFB and OFB. Modern cryptosystems all use CTR mode, and no new system I'm aware of uses CFB or OFB. - Chapter 8 "Public-Key Encryption" doesn't even mention elliptic-curve cryptography, despite almost all new cryptosystems being based on that in some form or another. This chapter also doesn't appear to mention RSA padding, which is crucial to a secure RSA implementation. - Chapter 9 "Hash Functions and Data Integrity" doesn't mention anything newer than SHA-1. But SHA-1 is thoroughly deprecated, and will be broken in the next few years. Just buy a new book instead; I hear good things about Cryptography Engineering, and I liked "An Introduction to Modern Cryptography" (more mathematical, less engineering-focused).

pieter_mj 10y ago
> But SHA-1 is thoroughly deprecated, and will be broken in the next few years. Why is this a problem? sha1 is not broken by design, it's only broken by current and future computing power.
- taejo 10y ago
  No, SHA-1's design is broken. The attacks still need a lot of computing power, but much less than they would if SHA-1 was secure.
- geofft 10y ago
  That's not true. SHA-1 is a 160-bit hash, which means that you'd expect it to take on average 2^80 hash computations to find a collision. The best attacks against full SHA-1 require more like 2^57 to 2^61 computations, and there are attacks against parts of SHA-1 that require quite a bit less than that (which indicates that the design is risky). https://en.wikipedia.org/wiki/SHA-1#Cryptanalysis_and_validation https://en.wikipedia.org/wiki/SHA-1#Cryptanalysis_and_valida... The difference between 2^60 and 2^80 is huge. If 2^80 operations take, say, a thousand years, it would take only about 8 hours to do 2^60 operations. (Also, there's the additional twist that SHA-1 isn't even the fastest known algorithm. If you switch to BLAKE2, you can get faster hashing, and the output is 256-bit, so the brute-force strength is 2^128, which more than makes up for each individual operation being a little faster. https://blake2.net/ https://blake2.net/)
geofft 10y ago
Another free and more up-to-date option is http://www.crypto101.io/ http://www.crypto101.io/ , but significant parts of the book are still in progress.
egjerlow 10y ago
What about the updated Cryptography engineering book by Schneier et al? Do you have any experience with it?
- nabla9 10y ago

j2kun 10y ago

Some chapters in this book (e.g. Chapter 4) contain very useful knowledge about practical algorithms for working with the underlying mathematical objects used as cryptographic primitives. Some that I found particularly useful in studying elliptic curve cryptography was the section on irreducible polynomials over finite fields.

curiousgal 10y ago

2001? Call an appeal to authority but I'll wait and see what tptacek has to say about this.