Dr. Dan's Handy-Dandy Chart For the RSA Code.
Setup: Armando wants to send Bob a message. Bob has an RSA key, so Armando
will use this to encrypt the message he sends to Bob. The evil enemy Fred will be
unable to crack the encrypted message, even though Fred knows the encoded message
and Bob's RSA key.
Number
p, q
n
r
m
s
x
y
What is it?
Who knows
it?
Two prime numbers (in Only Bob
real life, they are very
big prime numbers:
about 100 digits each)
pq
Everyone
What's it good for?
Used to find n, r, m
and s.
Class
Example
p=5
q = 17
Half of the key
85
released by Bob,
used to encrypt
messages.
A number that has no Everyone
The other half of
3
common factors with
the key released by
p-1 or q-1
Bob, used to
encrypt messages.
The least common
Only Bob
Used to decode the
16
multiple of p-1 and q-1
encrypted message.
A number such that
Only Bob
Used to decode the
11
rs mod m = 1
encrypted message.
The message before
Armando, but It's the message.
2, 21, 7
encryption; must be
Bob will
less than n
figure it out
The message after
Everyone, but It's the encoded
8, 81, 3
encryption
only Bob can message.
do anything
with it