From: m5@vail.tivoli.com (Mike McNally)
Date: Fri, 4 Mar 94 06:57:08 PST
To: Sergey Goldgaber <sergey@delbruck.pharm.sunysb.edu>
Subject: Re: Standard for Stenography?
In-Reply-To: <9403040134.AA15184@anchor.ho.att.com>
Message-ID: <9403041456.AA02863@vail.tivoli.com>
MIME-Version: 1.0
Content-Type: text/plain



Sergey Goldgaber writes:
 > I have never heard a serious, reputable claim about the unbreakablity of 
 > an algorithm. 

Maybe not, but if you've been paying atention you know of a great deal
of theory that support the intractability of solving certain problems
in realistic amounts of time.  Most PK cryptosystems are based on
relatively simple principles of mathematics.  It stretches the
imagination to think that the NSA somehow has solved the factoring
problem; I concede it's possible, but unlikely.

 > The point is, that in the real world, we'll never know if our algorithms 
 > are "good enough to withstand an opponent who has full documentation of 
 > your algorithms and methods lots of funds, and everything except your keys."

Depends on what you mean by "know", I guess.

 > > security-by-obscurity is a naive waste of time,
 > 
 > I still don't see why.

Well, you can't tell when you've been compromised, and you have no
rigorous way of demonstrating the robustness of your obscurity.  The
real problem, however, is that you'll have a hard time convincing
anybody else to participate.

You can hide all your valuables in a really clever place and do all
sorts of really clever secret things to protect them, and that may
make you feel secure.  However, you won't be able to convince me to
entrust *my* valuables to you unless you explain to me the details of
your techniques.

--
| GOOD TIME FOR MOVIE - GOING ||| Mike McNally <m5@tivoli.com>       |
| TAKE TWA TO CAIRO.          ||| Tivoli Systems, Austin, TX:        |
|     (actual fortune cookie) ||| "Like A Little Bit of Semi-Heaven" |