[GTALUG] Netgear 5-port Gigabit switch -- $10 ?

[James Knott]

On 03/27/2016 10:15 PM, Lennart Sorensen wrote:
> Good crypto protocols are very much designed to not be trivial to break
> even with some known plain text.  It is a known obvious attack so they
> are designed to protect against exactly that.

Yep, they've been doing that for centuries.  With a polyalphabetic
cipher, each time a letter occurs in the plain text, a different letter
is used in the cipher text.  This makes it impossible to use the
statistical methods used with monoalphabetic ciphers, where a plain text
letter always has the same cipher text letter.

https://en.wikipedia.org/wiki/Polyalphabetic_cipher