David Wong

cryptologie.net

cryptography, security, and random thoughts

Hey! I'm David, cofounder of zkSecurity, research advisor at Archetype, and author of the Real-World Cryptography book. I was previously a cryptography architect of Mina at O(1) Labs, the security lead for Libra/Diem at Facebook, and a security engineer at the Cryptography Services of NCC Group. Welcome to my blog about cryptography, security, and other related topics.

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Initial Permutations in DES

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I have to code a whitebox using DES encryption in a class. Which is pretty cool (I would have prefered doing it with AES but the other group got tails and we got heads).

Here is where the Stanford course I passed on Coursera shines. The explanation of DES on it is brilliant. I was wondering about the initial and final permutations that occurs in the algorithm though and Dan Boneh doesn’t really talk about it besides saying it’s not for cryptographic purposes.

I found a solution on a new sub-stackoverflow dedicated to Cryptography : http://crypto.stackexchange.com/questions/3/what-are-the-benefits-of-the-two-permutation-tables-in-des

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Initial Permutations in DES
01-22 blog
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