Re: Should be in crypto for John E. Hadstate Re: just stupid?

From: Timoleon (timoleon_at_gmail.com)
Date: 07/30/05


Date: Fri, 29 Jul 2005 22:40:49 GMT


Joe Peschel wrote:
> "Terry Ritter" <ritter@ciphersbyritter.com> wrote in
> news:1122661429.530199.136570@g43g2000cwa.googlegroups.com:
>
>
>>Joe Peschel wrote:
>>
>>>[...]
>>>No! Ritter was cited an as expert by this CryptoSMS fellow. His was
>>>an "Appeal to Authority" argument, and was in this case, a logical
>>>fallacy.
>>
>>Is every statement which gives a name an appeal to
>>authority error? Clearly not, and the distinction
>>is obvious:
>
>
> You're right, not every statement that gives a name is an appeal to
> authority. You were cited, however, as an authority. I believe that such an
> appeal is fallacious in that you are clearly not an authority, and you even
> admit it by describing yourself as an engineer.
>
>
>>As I see it, my name was cited for my particular
>>conclusions on Multiple Encryption, all of which
>>were developed from facts and reasoning, all of
>>which is extensively documented on my pages,
>>starting with my Glossary.
>
>
>>That is not Authority,
>
>
> Nonsense! You or you work was cited as being authoritative. Clearly, you do
> not have credentials as a cryptologist, so your opinions lack the weight of
> authority.
>
>
>>that is shorthand for an entire body of available
>>work.
>
>
> I'm afraind most of your work is unpublished, and much of your opinion on
> layering ciphers is, frankly, just that, opinion.
>
>
>
>>
>>>[...]
>>>In other words, if an authority is cited as an expert on the subject,
>>>he ought to actually be an expert on the subject. In this case, the
>>>issue is cryptology, and Mr. Ritter is an engineer and,
>>>unfortunately, not a cryptologist.
>>
>>I doubt Shannon would have called himself "a
>>cryptologist."
>
>
> Irrelevant. We're talking about your credentials. On the other hand, I
> doubt that Shannon would call himself a cipher designer.
>
>>Vernam actually was an engineer when he came
>>up with mechanical stream ciphering which then
>>led to the academically-loved one-time-pad.
>
>
> Irrelevant. We're talking about your credentials.
>
>
>
>>I do in fact claim expertise in particular areas
>>of cryptography, based on over a decade of work
>>and publication, including refereed articles and
>>issued fundamental patents in the field.
>
>
> Do you claim expertise on the concatenation of ciphers?
>
>
>>>[...]
>>>When we encrypt with multiple different ciphers, the resulting
>>>encryption needs to analyzed as if it was one (not a cascade of
>>>ciphers) cipher.
>>
>>I disagree: We do not insist on "analyzing" a
>>cipher with each exact key that may be used.
>>Yet a bad key can be a real issue: With some
>>conventional block ciphers, some keys could
>>possibly create the identity permutation, or
>>some other simple permutation, or a substantial
>>part thereof. Very few ciphers are proven to
>>produce no such result.
>
>
> We are not talking about analyzing each key; we're talking about analyzing
> the cipher that results from the concatenation of different ciphers.
>
>
>>Sometimes known weak keys are identified and
>>eliminated, but then that becomes a bias to
>>the randomness of the keys. Other times, the
>>probability of weak keys is known to be very
>>small and is then ignored. More often, the
>>probability of key weakness is simply unknown.
>>And then we still do not "analyze" the cipher
>>under each new key.
>
>
> This is just more irrelevant talk about keys.
>
>
>>A general system in which keying selected a stack
>>arbitrary ciphers on a message-by-message basis
>>could easily test adjacent cipher keys to assure
>>they differ, if that was thought worthwhile.
>
>
> I am not talking about analyzing individual messages or individual keys. I
> am talking about analyzing the cipher ABC that is the result of
> concatenating the individual ciphers A, B, and C.
>
> So far, you have presented no good reason to avoid thoroughly analyzing the
> concatenated cipher. If you are going to propose that such a cipher
> combination be used, the onus is upon you and upon peer review to analyze
> the beast.
>
> J
>
>
Joe, just for the record --- would you remind me of your own
credentials? Are you closer to, say, Don Coppersmith, or to Mok Kok-Sheng?

Thanks very much!

Tim

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