1. ## modular mathmatics

would using modular math be a good way of making a fast encryption system?

2. What do you mean by "modular maths"?

3. by modular math i believe hes talking about the % operator. it returns the remainder given two numbers, ie 10%4 is 2 and 100%10 is 0. as for how it can be used for a fast encryption system, i dont follow him there.

4. I think that creating an encryption system based on remainders would be quite difficult, or even impossible. All depends on what exactly you want to make with them: if you want a not too complicated and fast system, I believe it's impossible. Think how many ways there are to reach a particular remainder and how you could make the difference between those ways during encoding and/or decoding processes.

KC

5. Modular math as cire defined it is a great function to use for hash tables. It allows for very efficient searches (in O(1) time if done properly). Maybe sectac confused encryption and searching?? or maybe there is a way to use to make good encryption. I'm just rambling now.

Modular arithmetic forms the basis for number theory and many cryptosystems. A very simple, old, and well known example is the caesar cipher or shift cipher. Each letter of the alphabet is replaced with an integer from 0 to 25. A caesar cipher is then a function f(n) = (n+m) mod 26 where n is the integer representation of the letter and m is an integer representing the degree of shift. The caeser cipher is a private key cryptosystem, but public key cryptosystems are based on modular arithmetic also, a rather brilliant modern example is RSA. In RSA crypto each character is replaced with an integer and then those numbers are grouped into blocks of 4 digits. A 4 digit block of plaintext M is transformed into the the ciphertext C through the formula C = M^e mod n where n=pq. p and q are prime numbers (huge prime numbers) and e is an integer that is relatively prime to (p-1)(q-1). Then the cipher text is decrypted with the formula M = C^d mod n where d is an inverse of e mod (p-1)(q-1).

These are just a couple examples, but if you're really interested you should definitely read:
Handbook of Applied Cryptography by Alfred J. Menezes
Applied Cryptography by Bruce Schneier (aka the crypto bible)
A Course in Number Theory and Cryptography by Neal I. Koblitz

There are lots of other too, but these 3 are classics. The Handbook is fairly mathematically intensive and I don't know how mathematically inclined you are, but its the best crypto book out there IMHO and you can download the whole thing for free at http://www.cacr.math.uwaterloo.ca/hac/

7. I just like XOR Trees and simple algorithm layers based on a key....

- Noia

8. i beleived (at least i thought) that PGP used modular mathmatics , you password being translated into your key. But with HUGE numbers. something like, 238977238923999100399983%1229938854 = "watever"

9. Originally posted here by sectac
i beleived (at least i thought) that PGP used modular mathmatics , you password being translated into your key. But with HUGE numbers. something like, 238977238923999100399983%1229938854 = "watever"

well if you knew PGP used modular mathematics, why did you have to ask if it would be good for encryption?

10. because i was not sure if it was true or not, wondering if anyone can confirm or add any input to a new system im creating using modular mathmatics along with arrays

ttyl

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