Re: crypto for Joseph Ashwood, cryptologist or blowhard?

" "- Prof. Jonez©"" <jonez@norcom.ca> wrote in message
news:QjDse.43$JA3.2090@news.uswest.net...
> Joseph Ashwood wrote:
>> "Grumble" <devnull@kma.eu.org> wrote in message
>> news:d8m1o8$sr0$1@news-rocq.inria.fr...
>> > Prof. Jonez wrote:
>> >
>> > > How much of a moron must you be to not know the difference between
>> > > 3DES and 3DEA?
>> >
>> > I would, most definitely, love to be told the difference between
>> > 3DES and 3DEA. Pray tell.
>>
>> In this case (it's not a standard cipher) it refers to triple-IDEA in
>> EDE mode. This is based on the 3DES link on the website, which while
>> informative enough for this purpose is generally pointless without a
>> reference to the design of IDEA (which is patented and that would
>> probably be another way of getting rid of this company).
>>
>> The other proposed theory is the one that would actually make sense,
>> meet the designation used in cryptography, and be accurate. This
>> stems from the fact that the Digital Encryption Algorithm (DEA for
>> short) forms the basis of the Digital Encryption Standard (DES) which
>> would make 3DEA the same as 3DES.
>
>
> From: "Joseph Ashwood" <ashwood@msn.com>
> Newsgroups: sci.crypt
> Subject: Re: Cascading different algorithms?
>
> Message-ID: <wXUbe.2094$zu.569@newssvr13.news.prodigy.com>
> NNTP-Posting-Host: 67.118.12.54
>
> Date: Wed, 27 Apr 2005 23:08:12 GMT
>
>
> Actually 3DES was used because it was the most analyzed around, this came
> as
> a result of DES. If the key size were the only consideration we would have
> all switch to IDEA or Blowfish or any of the dozens of other good
> solutions.
> The tripling of the rounds that is the result of the process actually
> serves
> a very solid purpose, and the change of keys deals with the rest, leaving
> only those attacks that work on the structure of the new cipher (e.g. the
> attacks on 3DES work this way). 3DES was created because someone said why
> not, 3DES remained because it resisted everything anyone threw at it for
> over 2 decades, this was in large part because of the fundamental
> structure
> of the triple encipherment. The only situation where multiple encipherment
> with the same cipher would not increase security is in the unlikely case
> that it forms a group, IIRC there is actually a proof that Rijndael does
> not
> (Rijndael was named AES but much of the original theory is easier to find
> regarding Rijndael). The 7 layer encipherment is the next reasonable step
> in
> the process.
> Joe

Yes I did say that, but you will note that there is no reference made to
3-IDEA in any form. It might be a bit more difficult to understand because
of the structure I used, but I was advocating IDEA or Blowfish as the larger
keysize solution to the problem.
                Joe
Received on Thu Sep 29 21:44:33 2005