Re: dual sets of OTP's // intentional leakage of the misleading one // feasible ?

On 18 Jun 2005 22:02:42 -0700, "vedaal" <vedaal@hush.com> wrote:

>assume that Bob and Alice have a correspondence using a codebook, _CB_
>, of many OTP's,
>one for each message,
>
>can they now set up a 'decoy' codebook _dCB_ , composed of OTP's that
>will decrypt the ciphertext of the 'real' message, into a deliberate
>mis-informational message,
>and then 'leak' the codebook?
>
>(assume further, that they agree on pre-arranged unique ciphertexts for
>each message,
>but change the OTP's accordingly in both CB and dCB)
>
>
>in order for this to work,
>do the real and decoy plaintexts have to be exactly the same length?
>
>(not terrible if they do, since the 'real' one can just have extra
>padding as necessary, with a note that of where the padding starts and
>that it is done as filler to equal the length of the decoy message)
>
>is this scheme feasible?
>
>
>tia,
>vedaal

If the message texts are agreed upon in advanced then a OTP is
horribly inefficient means of encrypting. A simple number can
represent each message. For any reasonable number of messages
the number will be less than 32 bits.
The OTP method might be used where critical information such
as troop coordinates are encrypted in a fixed format message.
Flipping a single bit in the false OTP would put the troops in
a different location which could lead to a significant tactical
advantage.
Leslie 'Mack' McBride
remove text between _ marks to respond via e-mail
Received on Thu Sep 29 21:44:47 2005