Re: is this double CBC?

"Antony Clements" <antony.clements@xxxxxxxxxxx> wrote in message news:wkfzk.36361$IK1.28222@xxxxxxxxxxxxxxxxxxxxxxxxxxxxx
Then you were told wrong. For absolute proof of this, CTR mode is a stream cipher, AES using CTR mode operates on 128 bits at a time.

there is no data type that i am aware of that will allow 128 bits

So that could very well be the origin of part of your problem, you don't understand the difference between algorithm and implementation.


i did not claim it was a chaining mode, i asked if it was a chaining mode, look at the title of the thread "is this double CBC" it's a question not a statement. i have not claimed it is a cypher at all and especially not to improve security.

Whether you like it or not, what you have developed is a cipher. As it is a cipher it is subject to the same security requirements of a cipher. It fails under these requirements.

read the first sentence of the OP of this thread "through my own coding experiments it appears that i am creating a CBC mode on two seperate levels when i only intended one."

And you don't see how this directly contradicts "i did not claim it was a chaining mode?"

not once have i mentioned anything about a home brewed cypher

You keep denying it, but you have created one.

just because someone ie me is attempting to produce something that uses CBC or any other mode of operation,

It does not use CBC, it bears no reasonable resemblence to CBC. What you have created is a cipher, but you continue to claim it is not.

does not necessarily mean it is a cypher of any kind. i repeat, this is not a cypher, it is a permutation of an input.

And a block cipher is ..... a permutation of an input. No matter how much you deny it, every thing you say continually describes it as a cipher. And it fails completely in that context,.
Joe

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