[math-fun] Always off topic; always on target (SIMON and SPECK cryptosystems)

http://eprint.iacr.org/2013/404.pdf that was interesting - I did not know the NSA published stuff about cryptography. I agree this is simple and short and fast. The bad news is it looks to me like a poorly designed cryptosystem -- I can see very obvious changes which seem highly likely to be major security improvements.