h2g2 The Hitchhiker's Guide to the Galaxy: Earth Edition

your little example of wow theay could guess the message slightly inaccurate, ad the spaces in that fragment would likely also be encoded, possibly as any other alphanumeric character, or even removed totaly!

Why is it inaccurate?

The spaces might be encrypted or removed from the message but that doesn't change the situation, in fact OTP is so secure that it isn't necessary to worry about such things.

Cheers,

Cestus

quote from text "...assumes that the message 'SWPR MMWD' means 'SEND FOOD' ..."

if spaces were encoded too as would be likely, the message would either be encoded as say 'SWPRGMMWD' and mean 'SEND FOOD' or it could be encoded as 'SWPR MMWD' and mean 'HI I AM A' I believe that in such a code spaces are considered characters too.

True, but I felt it would help with the analogy to pull away from the detailed maths, especially since the maths of AES and RSA are way out of scope. In a computer-based cipher the spaces are characters, in most paper based ciphers the spaces are removed, however there is a precedent:

Soviet agents in Eastern Europe sometimes encrypted (having removed spaces) in the VIC cipher, then wrote out the message so it looked as though the spaces were retained, i.e. in plausible word-groups. The theory was that any attacker would assue that the cipher was OTP and give up before they even started trying to crack it

mmm, well thanks for explaining your motivs. Mmmm guess I'm stuck in the modern age though...