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Re: IPG Algorith Broken!
> > Ahh... an OTP isn't unbreakable. Its just so encredibly breakable that
> > you never know which break was the correct one ;)
>
> Note that Schneier says "perfect", not "unbreakable".
yes,
Perfect is a better term. Strictly speaking it is because there is no
finite unicity distance (the amount of ciphertext with which the
cipher can theoretically be broken). So, stricly speaking, for a given
message C and a prospective pad, P, out of a set of N pads which may
or may not be correct:
P(P|C) = N^-1
The length of C and the amount of ciphertexts given have no effect in
determining the key, nor is there any prospect of a know plaintext
attack as the pad is true random and the next bits are totally
independent of any others before them.
Of course the reason it is perfect is because there are many
different pads which give valid decryptions and there is no way of
knowing which one is correct.
IPG`s algorithm is definitely NOT an OTP and Don Wood is a snakeoil
merchant.
Datacomms Technologies web authoring and data security
Paul Bradley, [email protected]
[email protected], [email protected]
Http://www.cryptography.home.ml.org/
Email for PGP public key, ID: 5BBFAEB1
"Don`t forget to mount a scratch monkey"