Cryptography-Digest Digest #618, Volume #14 Fri, 15 Jun 01 15:13:00 EDT
Contents:
Re: survey (Ichinin)
Re: Help with Comparison Of Complexity of Discrete Logs, Knapsack, and Large
Primes (Stefek Zaba)
Re: Help with Comparison Of Complexity of Discrete Logs, Knapsack, (Mok-Kong
Shen)
integration question ("Tom St Denis")
Re: integration question ("Robert J. Kolker")
Re: integration question ("Tom St Denis")
Re: integration question (Paul Rubin)
Re: Help with Comparison Of Complexity of Discrete Logs, Knapsack, (Mok-Kong
Shen)
Re: integration question (Mok-Kong Shen)
Re: integration question ("Tom St Denis")
Re: integration question ("Tom St Denis")
Re: CipherText E-mail encryption ("Joseph Ashwood")
Re: Algorithm take 3 - LONG (was : Re: RSA's new Factoring Challenges: $200,000
prize. (my be repeat)) ("Joseph Ashwood")
Re: CipherText E-mail encryption ("Joseph Ashwood")
Tell me could this one-way function be somewhat secure ("Marko Lavikainen")
Re: Simple Crypto II, the public key... (Fat Phil)
Re: Simple Crypto II, the public key... ("Tom St Denis")
Re: Tell me could this one-way function be somewhat secure ("Tom St Denis")
----------------------------------------------------------------------------
From: Ichinin <[EMAIL PROTECTED]>
Reply-To: [EMAIL PROTECTED]
Subject: Re: survey
Date: Sun, 10 Jun 2001 08:56:00 +0200
Sam Yorko wrote:
> I (and everybody in the WLAN 802.11 community) would be >very<
> interested in something like this. With the amazing number of attacks
> against RC4 being published,
What amasing number of attacks against RC4? I know only these:
- The specific implementation of WEP.
http://www.isaac.cs.berkeley.edu/isaac/wep-faq.html
- Some specific attacks against SSL and the PRNG.
http://www.achtung.com/crypto/rc4.html#Algorithm_Analysis
- Equivalent keys in RC4.
> we would welcome a better solution for encryption of the
> data stream.
>
> Sam
I think there are alot of solutions to protect data going over
802.11,
If i am not mistaking:
- Certicom was working on some ECC kit for Pocket PC's a while ago.
- I *think* WinCE systems have support for MSCapi.
I know that there are other systems that do not ship with WinCE,
but take for instance a Dos Batch terminal (i saw that your NNTP
host was Symbol.com :o); one could write a DH plugin for those.
Sure, It is always better if the hardware did the encryption,
but one a flaw is found in hardcoded stuff, all the hardware
have to be replaced or updated, then software sounds like
a more dynamic choise as software can easily be distributed
to the clients.
Best regards,
Ichinin
------------------------------
From: [EMAIL PROTECTED] (Stefek Zaba)
Subject: Re: Help with Comparison Of Complexity of Discrete Logs, Knapsack, and
Large Primes
Date: 15 Jun 2001 17:11:02 GMT
In sci.crypt, [EMAIL PROTECTED] wrote:
> Are you tetched? Recognized literature is generally riddled with
> errors. One should assume that R&W contains many errors--even if they
> are all fixable. So what? Once you've gone to the trouble of reading
> and understanding it, where has it gotten you?
Hopefully, a deeper understanding of computability, and the upsetting (to
the tidy-minded) connection between completeness and decideability - at a
rather deeper level than browsing through "Goedel, Escher, Bach" could get
you :-)
Stefek
------------------------------
From: Mok-Kong Shen <[EMAIL PROTECTED]>
Subject: Re: Help with Comparison Of Complexity of Discrete Logs, Knapsack,
Date: Fri, 15 Jun 2001 19:26:18 +0200
[EMAIL PROTECTED] wrote:
>
> Mok-Kong Shen <[EMAIL PROTECTED]> writes:
> >
> > I am not a mathematician, let alone a logician. But from
> > what I know it seems to be true that one has learned that
> > the route taken by the two authors is a dead end only
> > (or mainly) 'through' the very knowledge of their failure.
>
> And once we know it was a failure, we make a note of the fact, and don't
> bother reading that work anymore. But we still sincerely love Russel and
> Whitehead as people. Does that make you feel better?
Whether we bother to read that book (I certainly wouldn't
do, because I guess it would be much too difficult for
me with my poor math knowledge and also because of
time availability) was never the point of a bit heated
debate between Gwyn and me, though. I wonder thus why you
think this issue is relavant for discussion or mention
here.
>
> > BTW, you must know better as mathematician of how to currently best
> > learn the foundations of arithmatics.
>
> Yes. To learn arithmetic, go to school.
I am very surprised to hear this from the mouth of a
mathematician. Maybe much has changed in the course of
time or the education is rather different in different
places of the world. Anyway, in the undergraduate analysis
course I had taken (for non-mathematicians) long time ago,
the foundations of arithmetics did occupied a few hours
or the prof's time and we had even a couple of questions
on an excercise sheet.
M. K. Shen
------------------------------
From: "Tom St Denis" <[EMAIL PROTECTED]>
Subject: integration question
Date: Fri, 15 Jun 2001 17:49:31 GMT
This is probably best suited for sci.math but it was in a crypto paper...
hehehe
We touched on integration just a tad in my high school math...
Integration is used to find the area under a curve right? So you find the
antiderivative and subtract the end points given?
A question in general about differential equations... one question in my
college text [nb calculus is a level III subject and I am in level I] says
find dy/dx in
y^3 = x^2
So I did
dy^3/dy = dx^2/dx * dx/dy
3y^2 = 2x * dx/dy
3y^2/2x = dx/dy
Can I just flip both sides to get dy/dx?
Another question: Can integration be performed over non-continuous domains?
i.e the integers?
--
Tom St Denis
---
http://tomstdenis.home.dhs.org
------------------------------
From: "Robert J. Kolker" <[EMAIL PROTECTED]>
Subject: Re: integration question
Date: Fri, 15 Jun 2001 13:56:11 -0400
Tom St Denis wrote:
>
> Another question: Can integration be performed over non-continuous domains?
> i.e the integers?
Descrete sums can be performed. For an infinite number of terms
you have to worry about convergence. In the formal sense sums
and integrals have a similarity. They are both linear operators,
sums and finite difference relate in a way similar to integrals and
derivatives.
Bob Kolker
------------------------------
From: "Tom St Denis" <[EMAIL PROTECTED]>
Subject: Re: integration question
Date: Fri, 15 Jun 2001 18:00:07 GMT
"Robert J. Kolker" <[EMAIL PROTECTED]> wrote in message
news:[EMAIL PROTECTED]...
>
>
> Tom St Denis wrote:
>
> >
> > Another question: Can integration be performed over non-continuous
domains?
> > i.e the integers?
>
> Descrete sums can be performed. For an infinite number of terms
> you have to worry about convergence. In the formal sense sums
> and integrals have a similarity. They are both linear operators,
> sums and finite difference relate in a way similar to integrals and
> derivatives.
I noticed this. I wanted to proof
Sum(x^3) = Sum(x)^2
Where Sum() is the sum of the expression overall a series of consecutive
values of 'x' [say 0..99].
I proved it using
Sum(x) = x(x - x_0)/2 = x(x - 0)/2 = x^2/2
Sum(x)^2 = (x^2/2)^2 = x^4/4
Then
Sum(x^3) = Int(x^3 dx) = x^4/4
Thus QED.
Is that valid?
Tom
------------------------------
From: Paul Rubin <[EMAIL PROTECTED]>
Subject: Re: integration question
Date: 15 Jun 2001 11:24:09 -0700
"Tom St Denis" <[EMAIL PROTECTED]> writes:
> I noticed this. I wanted to proof
>
> Sum(x^3) = Sum(x)^2
>
> Where Sum() is the sum of the expression overall a series of consecutive
> values of 'x' [say 0..99]...
> Sum(x^3) = Int(x^3 dx) = x^4/4
>
> Thus QED.
>
> Is that valid?
Of course not. 0^3 + 1^3 + 2^3 + 3^3 = 1 + 8 + 27 = 36.
3^4/4 = 81/4 = 20.25.
Geez, think a little.
Your next book to read is "Calculus", by Michael Spivak, 2nd ed.,
Publish or Perish Press. Accept no substitutes. You might have to
look for a used copy.
------------------------------
From: Mok-Kong Shen <[EMAIL PROTECTED]>
Subject: Re: Help with Comparison Of Complexity of Discrete Logs, Knapsack,
Date: Fri, 15 Jun 2001 20:29:59 +0200
"Douglas A. Gwyn" wrote:
>
> Mok-Kong Shen wrote:
> > I am not a mathematician, let alone a logician. But from
> > what I know it seems to be true that one has learned that
> > the route taken by the two authors is a dead end only
> > (or mainly) 'through' the very knowledge of their failure.
>
> No, the futility of their endeavor was demonstrated by
> others. The only role that PM played was to provide a
> well-known example of a logical system that could be
> Goedel-numbered. A number of other axiomatic systems
> could have been used as an example instead of PM.
I NEVER argued on the point of futility. (May I repeat
again that early in our discussions I already stated
that their goal failed ?) I only maintained that the
content of the book is apparently not mathematically
wrong (wrong in the sense of wrong deduction -- again
this has been repeated many times by me).
> > ... I happened to read in a literature saying that,
> > although their work failed, that work as such has an
> > essential (positive) influence on the advancement of the
> > following researches undertaken by others in that and
> > related fields.
>
> Not to my knowledge (which is extensive although not
> exhaustive). I actually *read* (most of) PM in high
> school, and despite frequently being involved in
> research involving logic and formal systems, I have
> found no use at all for the contents of PM, not even
> the notation (which is cumbersome).
Not to your knowledge. But I read from a literature.
(I definitely don't assume that you know all math
literatures.) On the other hand I very highly esteem
and envy your capability of being able to read most of
Principia Mathematica while in high school. (I guess I
definitely wouldn't be able to understand that kind of
math AT ALL before entering university. For it concerns
some deeper stuffs than the common predicate calculus,
I presume, and I had learnt only a ridiculously tiny bit
of formal logic in my school time.)
>
> > that that book has set forth a good style of rigor in
> > attempting axiomatization of arithmatics that stimulates
> > later similar works in logics.
>
> There is no doubt that PM served as an impetus to the
> formalist approach to mathematics. However, several
> other contemporary logicians were just as concerned
> about rigorous methods of deduction. PM is sometimes
> used as a standard example, but only as an example.
>From what I read that's apparently considered the
first serious attempt in that direction. Does being
the first not count at least a little bit?
> > BTW, you must know better as mathematician of how to
> > currently best learn the foundations of arithmatics. In a
> > math course for non-mathematicians that I had taken very
> > long time ago, that was dealt with very quickly with the
> > Peano axioms. But I remember that my fellow-students who
> > majored in math studied a book written by Landau on that
> > topic and that book was not extremely thin (though
> > certainly not comparable at all in extent to that of
> > Whitehead and Russell) and had an appearance of some
> > difficulty for me (as least as far as my impression of
> > that time goes). So, pending more knowledge of experts'
> > view, I am yet not very sure that the two authors had
> > extremely overexagerated in the treatment of their
> > subject in the sense that they wrote in unnecessarily
> > long-winded and expensive (for the readers' energy)
> > ways.
>
> ? PM wasn't "long-winded"; it was almost entirely
> formalism. It isn't that axiom sets are especially
> complicated; the problem is that it takes a *lot* of
> formalism to spell out *every* step in a logical chain
> of deduction when only very basic axioms are used. So,
> back to 1 + 1 = 2, there are lots of ways to prove that,
> but the details depend on what one can start with.
> Using only very low-level concepts and axioms forces a
> lot of development that is not necessary when one can
> take for granted higher-level concepts and theorems.
As I said previously, I haven't even touched that book.
But that theoretical work is certainly not meant to
be read by non-mathematicians but by those mathematicians
that specialize in logics, I suppose, and in mathematics
there is sort of general desire of founding stuffs on as
low a level as possible, as far as I (as layman) could
discern. After such a hopefully solid foundation has
been built, one then proceeds to higher levels, much
like in building construction, I think.
>
> I have a paper on Jaskowski's system of deduction that
> I hope to post on a Web site some day; it contains
> examples of strict step-by-step deductive reasoning,
> and can serve as a demonstration of the fact that such
> derivations are typically long, tedious, and boring.
I know that logical deductions could be awkward, from
my (chance) familiarity with the field of automated
deductions.
>
> > Another thing that I happened to know and may be
> > interesting in this connection is that not quite
> > long ago in a certain university a math prof spent
> > one 'entire' semester to explain the foundations of
> > arithmetics such that, because of consequently less
> > time available to treat other stuffs in the succeeding
> > semesters, the students under that prof were found to
> > be at disadvantages to work out the normal types of
> > math exam sheets (where the foundations of arithmatics
> > are rarely an issue) in comparison to fellow-students
> > that were under other profs who treated the topic of
> > foundations of arithmetics rather tersely and quickly.
> > So it seems correct to say that even under the 'current'
> > mathematics professors opinions could essentially differ
> > as to what details/extents an upcoming mathematician
> > should learn about the foundations of arithmeics.
>
> Of course; people have differing opinions on almost
> anything. It sounds like that professor did the
> students a disservice. On the other hand, perhaps they
> were so poorly prepared before entering the course that
> the professor saw it would be a waste of time to develop
> more advanced topics until there had been remedial work
> on the basics. I see this in high school math classes,
> where the majority of the students don't have even an
> elementary-school level of competency in math.
In that case it was almost certainly a disservice, because
there are nowadays too much different other stuffs that
are to be taught to the undergraduates in an almost
unvaried time span (in comparion with, say, half a
century or longer ago), I believe. But the stuff concerned
above was, according to what I heard from my informant,
definitely not of the kind taught in high school (anyway
not in the school I attended while I was young.) It should
be, as far as I understood, sort of at the level of
Landau's book that I mentioned, which isn't simple in my
humble view.
M. K. Shen
============================
http://home.t-online.de/home/mok-kong.shen
------------------------------
From: Mok-Kong Shen <[EMAIL PROTECTED]>
Subject: Re: integration question
Date: Fri, 15 Jun 2001 20:34:26 +0200
Tom St Denis wrote:
>
> This is probably best suited for sci.math but it was in a crypto paper...
> hehehe
>
> We touched on integration just a tad in my high school math...
I deduce that there is highly probably quite a difference
in school education between Canada and US. Douglas Gwyn
just told us he was able to read most of Principia
Mathematica in high school.
M. K. Shen
------------------------------
From: "Tom St Denis" <[EMAIL PROTECTED]>
Subject: Re: integration question
Date: Fri, 15 Jun 2001 18:36:33 GMT
"Paul Rubin" <[EMAIL PROTECTED]> wrote in message
news:[EMAIL PROTECTED]...
> "Tom St Denis" <[EMAIL PROTECTED]> writes:
> > I noticed this. I wanted to proof
> >
> > Sum(x^3) = Sum(x)^2
> >
> > Where Sum() is the sum of the expression overall a series of consecutive
> > values of 'x' [say 0..99]...
> > Sum(x^3) = Int(x^3 dx) = x^4/4
> >
> > Thus QED.
> >
> > Is that valid?
>
> Of course not. 0^3 + 1^3 + 2^3 + 3^3 = 1 + 8 + 27 = 36.
> 3^4/4 = 81/4 = 20.25.
Oops ... that should be x^4/4 as in x is the highest #, not part of the sum.
Hmm... something a foot... I had this figured out earlier....
Tom
------------------------------
From: "Tom St Denis" <[EMAIL PROTECTED]>
Subject: Re: integration question
Date: Fri, 15 Jun 2001 18:50:03 GMT
"Mok-Kong Shen" <[EMAIL PROTECTED]> wrote in message
news:[EMAIL PROTECTED]...
>
>
> Tom St Denis wrote:
> >
> > This is probably best suited for sci.math but it was in a crypto
paper...
> > hehehe
> >
> > We touched on integration just a tad in my high school math...
>
> I deduce that there is highly probably quite a difference
> in school education between Canada and US. Douglas Gwyn
> just told us he was able to read most of Principia
> Mathematica in high school.
So what? Apparently you failed at statistics.
You base your observation on ONE canadian and ONE american.
Tom
[if you detect irony in this post maybe not all is lost]
------------------------------
From: "Joseph Ashwood" <[EMAIL PROTECTED]>
Subject: Re: CipherText E-mail encryption
Date: Fri, 15 Jun 2001 11:30:45 -0700
You seem to have failed yet again to grasp even the tiniest concept.
I never propsed Base-64 encoding for encryption. I suggested Base-64
encoding in order to make arbitrary data representable as printable ASCII,
which would make it easily encodable by you pitiful algrotihm.
And quite frankly I don't give a <editted for content> what CipherText can
sent without, because it is obviously sent without security.
Joe
"Prichard, Chuck" <[EMAIL PROTECTED]> wrote in message
news:ugbW6.1153$[EMAIL PROTECTED]...
> Base-64 is an encoding scheme for transmission. It is not encryption.
>
> CipherText content is suitable for transmission without time-consuming
> Base-64 encoding.
>
> -C. Prichard
>
>
------------------------------
From: "Joseph Ashwood" <[EMAIL PROTECTED]>
Subject: Re: Algorithm take 3 - LONG (was : Re: RSA's new Factoring Challenges:
$200,000 prize. (my be repeat))
Date: Fri, 15 Jun 2001 11:44:43 -0700
Crossposted-To: sci.math
"Michael Brown" <[EMAIL PROTECTED]> wrote in message
news:5plW6.533$[EMAIL PROTECTED]...
> Unfortunately, I think it might be the same case for this one. It breaks
trying
> to do 23*29 :()
> I think I know why, but I don't know how to fix it (apart from pushing it
into
> non-linear boolean equations which doesn't help).
Well I was hoping. If you can get it to work for arbitrary numbers that'd be
great. If not don't feel too bad, at least you didn't have to retract
comments that made headline news.
Joe
------------------------------
From: "Joseph Ashwood" <[EMAIL PROTECTED]>
Subject: Re: CipherText E-mail encryption
Date: Fri, 15 Jun 2001 11:43:57 -0700
"Prichard, Chuck" <[EMAIL PROTECTED]> wrote in message
news:z4eW6.1160$[EMAIL PROTECTED]...
> The CipherText application can be downloaded and examined.
But the algorithm cannot be simply downloaded, which immediately flags it
as, I'm not even going to say it again.
> You would have learned that as a user you have the ability to setup a
> large list of assorted contacts, their email addresses and undividual
> unique keys.
Blah, blah, blah. Who cares? If it has no security, it's worthless as a
security application. No further debate is necessary for me to decide that
I'm not even going to say it again.
> You would have learned that you can easily communicate using Outlook
> Express to receive all of your encrypted CipherText messages without
> having to differentiate between the two kinds of messages on your server
> and fiddling around with two clients.
More Blah. I don't care how well it integrates with program X, I'm concerned
about the lack of security that makes it so very easy to decide that I'm not
even going to say it again.
> You would have experienced the prototype demonstration of an idea that is
> being rapidly developed to fruition as a product.
Yeah the rapid development thing again. But later you go on to say that it
took a matter of years? Doesn't that make it a little I'm not even going to
say it again.
> You would have been impressed with use of the Outlook Express product in
> a manner that you have probably have not been priveleged to have yet
> experienced.
Actually I'm rather hard to impress with a program that is so obvously I'm
not even going to say it again.
> CipherText is the integration of several technologies made possible for
> the most part by Microsoft.
Oh hey, there's a way to inspire trust in the security, claim association
with company that has cost more security than any other. Do you believe that
this makes your program any less I'm not even going to say it again.
> I have merely implemented the ASCII
> encryption algorithm in order to work with existing messaging
> technologies in a manner that I perceived necessary a couple of years
> ago. For me, arriving at this place in my development is not an end but a
> beginning.
You've spent a couple of years on this? Why? It's a worthless project, it's
worthless in terms of knowledge, it demonstrates nothing worth being new,
it's just I'm not even going to say it again.
> Your input imparts very little that is constructive and lacks definitive
> content that can be regarded as having any real value.
My input is meant for one and only one purpose to make sure new people,
people who have not had the benefit of even the smallest education in
security don't use a product which is so obviously I'm not even going to say
it again.
> I'm at work
> realizing the tradeoffs in working with STRING vs. BYTE array data types
> in VB applications to overcome the deficiencies.
See now that's the first problem, it's very hard to do real cryptographic
work in VB, might I suggest you move to a real language for crypto for your
next I'm not even going to say it again.
> However the existing
> demonstration provides the means to encrypt a short 2K message and send
> it to anyone who is new to computers and encryption without confusing
> them with key exchanges, public keys, private keys, transfer encoding and
> security providers.
Gee last time I checked all of these were dealt with very cleanly in just
about everything. Just looking around at the window I'm typing in I click a
button and it signs in 2 different ways, or encrypts in 2 different way, and
key exchange, public keys, private keys, trasnfer encoding and security
providers (if even necessary) are hidden from the basic user. So your
additional claim is that you can now offer a new I'm not even going to say
it again.
You really should have spent your time better ways. Because I quite frankly
don't care how much time you've wasted on this thing. It's worthless and I
intend to make sure that until the algorithm can be analyzed that it fails,
and is fully recognised as the to say the least braindead idea that it is
(Ok, so I couldn't resist saying it at least once more).
Joe
------------------------------
From: "Marko Lavikainen" <[EMAIL PROTECTED]>
Subject: Tell me could this one-way function be somewhat secure
Date: Fri, 15 Jun 2001 22:05:08 +0300
I was wondering that when using hash-function, there is always a change for
collision. So, could not one use, say, two hash functions with different
properties.
I'll demonstrate it with these two matrixes. Think that every single node in
matrix means a hash value for a specified document. So, if the document is
in the same place for both matrixes, there is no two common hash values for
any document. So, even if there are different documents in one matrix, which
has the same hashvalue, one cannot find it for both matrixes.
So, does this mean ultimate perfectly secure hash function, or have I
forgotten something
THE MATRIXES
============
1 2 1 2
4 3 3 3
2 4 4 1
4 1 2 4
2 4 3 4
2 1 4 1
3 2 3 2
1 4 1 3
------------------------------
From: Fat Phil <[EMAIL PROTECTED]>
Subject: Re: Simple Crypto II, the public key...
Date: Fri, 15 Jun 2001 21:54:44 +0300
Tom St Denis wrote:
> Phil Carmody wrote:
> > Tom St Denis wrote:
> > > Of course [for anyone in the dark] a mod operation with these modulos is
> > > just a shift right n bits and an addition.
> > >
> > > So "mod 255" would be
> > >
> > > a = ((a >> 8) + a) & 255;
> >
> > Stick 65535 into that :-)
>
> 65535 cannot be the product of two #'s less than 255.
In "a mod operation" (your words) products don't enter into it.
If you had said "in a mulmod (of numbers <255)", then your defence would
be valid, but you didn't.
Swat up on "programming by contract" next time you have any spare time.
Phil
------------------------------
From: "Tom St Denis" <[EMAIL PROTECTED]>
Subject: Re: Simple Crypto II, the public key...
Date: Fri, 15 Jun 2001 19:08:34 GMT
"Fat Phil" <[EMAIL PROTECTED]> wrote in message
news:[EMAIL PROTECTED]...
> Tom St Denis wrote:
> > Phil Carmody wrote:
> > > Tom St Denis wrote:
> > > > Of course [for anyone in the dark] a mod operation with these
modulos is
> > > > just a shift right n bits and an addition.
> > > >
> > > > So "mod 255" would be
> > > >
> > > > a = ((a >> 8) + a) & 255;
> > >
> > > Stick 65535 into that :-)
> >
> > 65535 cannot be the product of two #'s less than 255.
>
> In "a mod operation" (your words) products don't enter into it.
> If you had said "in a mulmod (of numbers <255)", then your defence would
> be valid, but you didn't.
> Swat up on "programming by contract" next time you have any spare time.
You can't ever get a # greater than 255*255 in any operation. Think about
it. The only way to get 65536 is todo 256*256 where 256 is not an element
of the ring thus no a valid operation
Tom
------------------------------
From: "Tom St Denis" <[EMAIL PROTECTED]>
Subject: Re: Tell me could this one-way function be somewhat secure
Date: Fri, 15 Jun 2001 19:09:16 GMT
"Marko Lavikainen" <[EMAIL PROTECTED]> wrote in message
news:9gdm8n$2us$[EMAIL PROTECTED]...
> I was wondering that when using hash-function, there is always a change
for
> collision. So, could not one use, say, two hash functions with different
> properties.
Generally yes. But you're spreading the trust.
tom
------------------------------
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