New answers tagged


I don't think there is a name for this special kind of property, but it is a clear hint for polyalphabetic substitution ciphers. It is a special kind of polyalphabetic substitution cipher. The first alphabet is a normal random key, while each successive alphabet is generated by a one-character right shift of the previous alphabet. As a result there are as ...


Ciphertext expansion, or expansion ratio are terms used to indicate this.


$\mathbf{Z}_2^b$ is the direct product of $b$ copies of $\mathbf{Z}_2$ ($\mathbf{Z}_2 \times\cdots \times \mathbf{Z}_2$, $b$ times). That is, its elements are $b$-tuples of elements of $\mathbf{Z}_2$, with both addition and multiplication defined componentwise. If $b > 1$, it is not a field. In fact it is not even an integral domain, because $(0,1)\times (...

Top 50 recent answers are included