# Proposal for cryptography project

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Hi.
I am currently studying a course about cryptography and our tutor has
given us the opportunity to create a project about any theory that is
part of the curriculum. The problem however is that I have to come up
with a project after only 3 hours of lecturing, which barely
encompasses a small part of the entire curriculum.

Therefore I hope some of you might give me an idea for a project
topic.

So far we have learned briefly about the classical cryptography
(substitution and transformation from Ceasar through DES, including
mono-/polyalphabetic, statistical problems, block and stream
cyphering). Still we have only just begun, and my understanding
therefore feels limited.

royend.

## Re: Proposal for cryptography project

Try out:
Backdoors for RSA key generation scheme.
Details here:

http://eprint.iacr.org/2002/183.pdf

This subject-matter is quite easy and interesting.

--
Z. Karno

## Re: Proposal for cryptography project

You could try to look at the ScottNu ciphers
they are simple in theory and yet no one has
broken them. One so called exert clained that
the slide attack would work but a guy named Horace
showed that was wrong.

http://bijective.dogma.net/crypto/index.htm

there is a time machine thing some where on net
it was first posted on xoom years ago.

Scott4u  based on 4 bit single cycle S table so only
4! keys  24 possible keys use 4 bit sub blocks.

Scott16u based on all possible single cycle 16 bit
wide tables  or 16! 20922789888000 possible values
this one use 16 bit sub blocks but any file over a
certain number of bytes can be encrypted again its
allows the use of any possible single cycle table.

Scott19u allows any 19 bit wide single cycle S to be the
key this gives 19! 121645100408832000 possible values

Again it works on several passes through the input file useing
19 bit chunks as the sub block unit works on any file more
than a few bytes long. 19 was made since at the time
20 was to big for a floppy to hold the key. The multple
passes can be thougjt of having the file in a ring where the
bottom of file bits are wrapped to the top. This is the hardest
one to port. It was all done on a pc using GNU C

David A. Scott

Expect lots of flak from the crypto vocal community if
you work on this. Its not what the experts like yet
they can't break it. Use to have several cash contests
no one broke it. An early nonU  version was broken by Paul
Onions because at that time I never considered choosen
plaintext attack as valid. Yet as I grow I realize that is
a valid concern so I added the onion pass to prevent such
a thing. I could be wrong but If you find a way like Paul did
and actually break scott19u you would be a hero and I am
sure you could get a job with the NSA or some other agency
in China or you could be killed. Who knows.

--
My Crypto code
http://bijective.dogma.net/crypto/scott19u.zip
http://www.jim.com/jamesd/Kong/scott19u.zip old version
My Compression code http://bijective.dogma.net /
**TO EMAIL ME drop the roman "five" **
Disclaimer:I am in no way responsible for any of the statements
made in the above text. For all I know I might be drugged.
As a famous person once said "any cryptographic
system is only as strong as its weakest link"