Re: simple math question

• From: tom@xxxxxxx
• Date: Thu, 16 Apr 2009 16:10:22 -0700 (PDT)

On Apr 16, 1:38 pm, pubkeybreaker <pubkeybrea...@xxxxxxx> wrote:
"Implementing AES" is not doing cryptography.  It is writing code
from a well documented cookbook.

Um, optimizing it means you have to understand the math of the design
and perform design tradeoffs to exploit it's structure. We can't all
be rocket surgeons like you.

Multi-precision arithmetic is part of cryptography.

Hi, I'm Tom St Denis, author of LibTomMath and TomsFastMath, a text on
the subject, and I don't have an advanced degree in mathematics. Can
we put the ego stroking aside?

As for why trig is needed:  Try analyzing anything to do with
elliptic curves without knowledge of periodic functions.

I've implemented performance ECC as well. Using algorithms for which
I haven't seen implementations of.

It shows a fundamental lack of background mathemtics.  The ability to
work with trig functions; to understand them, to understand their
relation to general functions of a complex variable; to understand
groups on the unit circle,  etc. etc. etc.  is a requirement.

Depends on what you're doing. I can fully understand differential
cryptanalysis AND not know anything about trig. Are you saying
cryptanalysis is not part of cryptography?

We are not discussing the implementation of crypto methods.  That
can be done cookbook fashion from well-documented sources.  We are
discussing the ability to design and analyze ALGORITHMS.  Someone
who can't (or hasn't) learned trig,  will not be able to do the
former.

You're both very condescending, and no offense, but full of shit.
Implementing optimized crypto is not a matter of copy/paste from
"cookbooks." If it were you'd see more LibTomMaths floating around
[or TFM or LTC or ...]. It takes some brains to put it together, but
you don't have to be a math PhD to be capable. Not only that but when
I was referencing a lot of standard material like HAC, I had to
correct things [and people helped] that were wrong with them [or just
plain missing].

I'd say you need far more algebra than trig.

But that's just being pedantic. My point is you don't have to be you
to be a "cryptographer." I implement algorithms, I've developed
theory, and designed algorithms. And I don't hold an advanced degree,
and am nowhere near a math genius. I think we can all agree there is
a large range of different tasks in the crypto field involving
different levels of education and specialty.

You've really got to stop being so dismissive.

Tom
.