Take the 2-minute tour ×  GOing over a lecture on DES I got most
of it except WHERE DOES DES KEY COME FROM? Does an authority
give you the key or what? Simple language please  share|improve
this question  closed as not a real question by Oded, Jim G.,
Walter, Yusubov, pdr Oct 12 '12 at 13:05   Which other (somewhat
modern) ciphers do you know? Where does the key for those some
from? –  delnan Sep 28 '12 at 20:53 @delnan and does it use a
48-bit key or a 56-bit key??? The professor goes on to say that
there are 48-bit round keys. –  Fasih Khatib Sep 28 '12 at 20:53
I dont know a lot, this is my first –  Fasih Khatib Sep 28 '12
at 20:53 Ok, so from the 56-bit key a sub-key of 48-bits is
generated right? –  Fasih Khatib Sep 28 '12 at 20:57 It's not
easy to explain without either getting bogged down in theory or
omitting dangerously many criteria, but the short and inaccurate
version is that you generate a random number of the appropriate
order of magnitude. I'm hoping for someone with more crypto
knowledge than