Comparing Cryptographic Key Sizes II
I got quite a few useful comments on the key comparison summary I
posted earlier. Even some people said they found it useful. Mark
Grant improved the readability, plus other suggestions. Peter Trei
urged me to actually re-read the Wiener paper to quote the figures
correctly rather than from memory. Also Peter raised issues to do
with how to compare hardness to break DES against 512 bit RSA. There
is now an aside more technical note explaining the issues. I think I
stand by my original comparison of "roughly equal", because depending
on how you view it, it'll come out 10x cheaper, or 10x harder.
(Memory being one hurdle each participating workstation needing of the
order of 128 Mb; the other hurdle being the existance of a machine
large enough to reduce the matrix which results from all the
relations).
I don't think we can explain it any more technically and expect it to
be useful to a journalist. We need a gross generalisation: is it
approx as hard, is it 100x harder. They don't want to hear about
space complexity, the matrix reduction phase (RSA) nor known plaintext
memory trade offs (DES). If we don't supply the gross generalisation,
they will do it themselves to make it palatable for their readers.
With less understanding of the subject, their generalisation is likely
to be even wildly inaccurate than the generous error bars on ours.
This is not an insult to journalists. Crypto is a technical,
complicated field. I wouldn't contemplate making estimates in other
peoples fields.
Further discussion of course still sought (rip it apart pessimists on
crypto estimates). Here's the new improved version.
Adam
--
Have *you* exported RSA today? --> http://www.dcs.ex.ac.uk/~aba/rsa/
print pack"C*",split/\D+/,`echo "16iII*o\U@{$/=$z;[(pop,pop,unpack"H*",<>
)]}\EsMsKsN0[lN*1lK[d2%Sa2/d0
At 23:33 +0100 6/24/97, Adam Back wrote:
I don't think we can explain it any more technically and expect it to be useful to a journalist.
Um, some of us journalists have *gasp* taken computer science classes, programmed in machine code, crafted compression routines, written our own Unix shells, etc. Now, I don't want to start a "who's the geekiest geek" contest, since y'all will win hands-down -- but I want to point out that while we may not be crypto-whizzes, not all of us are entirely clueless either. -Declan
Declan McCullagh
At 23:33 +0100 6/24/97, Adam Back wrote:
I don't think we can explain it any more technically and expect it to be useful to a journalist.
Um, some of us journalists have *gasp* taken computer science classes, programmed in machine code, crafted compression routines, written our own Unix shells, etc.
Now, I don't want to start a "who's the geekiest geek" contest, since y'all will win hands-down -- but I want to point out that while we may not be crypto-whizzes, not all of us are entirely clueless either.
Present company excluded, naturally :-)
We all know you're not clueless. I agree with most of your articles,
usually idealogically, and technically also. You're perhaps more of a
crypto anarchist, libertarian type fighting for the cause using
journalism as a vehicle for prosletizing than yer average 'hack anyway :-)
But the low level of crypto understanding of some journalists clearly
shows through in the articles they write, where there are garbled
facts, non-standard terminology, and complete falsities. Half the
articles you read which mention crypto make you wince at the
innacuracies and misconceptions. The balance given to FBI and NSA
scare stories varies also.
It's good that there are a few technically minded journalists. I know
a few myself.
Adam
--
Have *you* exported RSA today? --> http://www.dcs.ex.ac.uk/~aba/rsa/
print pack"C*",split/\D+/,`echo "16iII*o\U@{$/=$z;[(pop,pop,unpack"H*",<>
)]}\EsMsKsN0[lN*1lK[d2%Sa2/d0
At 9:25 PM -0700 6/24/97, Declan McCullagh wrote:
At 23:33 +0100 6/24/97, Adam Back wrote:
I don't think we can explain it any more technically and expect it to be useful to a journalist.
...
Now, I don't want to start a "who's the geekiest geek" contest, since y'all will win hands-down -- but I want to point out that while we may not be crypto-whizzes, not all of us are entirely clueless either.
I'm not worried about the journalist-with-a-clue. I am worried about Joe citizen (the restless "sheepie"). I believe deep in my heart that if Joe citizen understood the issue, he'd say, "No way am I going to let some government bastard paw through my personal business." Based on this belief, I applaud Adam's attempt to explain the crypto issues in simple language. ------------------------------------------------------------------------- Bill Frantz | The Internet was designed | Periwinkle -- Consulting (408)356-8506 | to protect the free world | 16345 Englewood Ave. frantz@netcom.com | from hostile governments. | Los Gatos, CA 95032, USA
participants (3)
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Adam Back
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Bill Frantz
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Declan McCullagh