Re: Confirmation of Shannon's Mistake about Perfect Secrecy of One-time-pad

And note that the probability distribution on C is always the
same, no matter what the probability distribution on M.
So no observation of C can give us any information about the
probability distribution on M.
------------I see the probability distribution on M is changed due to
OPT,but no the value of C. But that does not mean Perfect secrecy.
Posterior=prior

In particular, observing
C=0 cannot change how likely we consider the uniform
distribution on M.
-----------will you express clearly

According to the information that cryptanalysts got beforehand,
they can get the prior probability of plaintext as P(M=0) = 0.9 and
P(M=1) = 0.1. Later the ciphertext C=0 is intercepted. When only
considering C=0 and the cryptosystem (regardless of the prior
probability of plaintext), we can educe that the plaintexts are
equally likely,


No. This is simply false. We can educe nothing about the
probablities of the plaintext.
-----you do not think roundly, the probability changes.

for there is a one-to-one correspondence between all
the plaintexts and keys for C=0.


So what? There is no relationship between the probabilities.

---what is perfect secrecy.

.

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