hi, The methodology is very simple again.
'A' uses a very strong crytographic algorithm which would be forced out by rubber horse cryptanalysis Now if Aice could give another key k` such that the cipher text (c) decrypts to another dummy plain text(D) the secret police gets to read the dummy plain text(D) using the surrendered key k` without compramising the real plain text(P). goes like this. p=plain text c=cipher text D=dummy plain text k=oiginal key k`=dummy key. Now A encrypt using a good asymmetric key algorithm. Now A has cipher text C. Now A takes her Dummy plain text (D) and she, C (xor) D=k` Now to the secret police she can surrender k`. The secret police decrypts dummy plain text D as D=c(xor)k` She can now say that she used k` as one time pads to encrypt C. There is no way to prove that k` is not a valid key unless they ever get hold of k. hOW ever as what is said,it doesn't look like it will work. Regards Sarath. __________________________________________________ Do you Yahoo!? Yahoo! Mail Plus – Powerful. Affordable. Sign up now. http://mailplus.yahoo.com
