Create a Strong Password Appendix 2 - Ciphers

Ciphers

The password strength checkers all say NOT to use real words.  So one method of beating that system is to convert a real word using a cipher.

There are many types of Ciphers, They can be used in any combination to create a strong password.  I'll discuss several here.

Backwards Cipher:

PASSWORD = DROWSSAP
Simply spell your word(s) backward.  This is pretty good, but common words can be broken quite easily.     Never use MadamImAdam in a backwards cipher  (hint it is the same both ways).

Alternating Cipher

In an alternating cipher, you take 2 words and write them using a letter from every other word, like this  (I'll spell the 2nd word in all caps to help you see):

the words lettuce purple would convert to   lPeUtRtPuLcEe

To make this more tricky, you could spell the 2nd word backwards. like this (again, 2nd word is in all caps)

the words Lettuce Purple would convert to  lEeLtPtRuUcPe


Substitution Ciphers.

The can be created in any combination.  For Instance:

Simple Substitution Cipher:

ABCDEFGHIJKLM
NOPQRSTUVWXYZ

Simply substitute the letter above or below it.  For Instance:

If I substitute the letters in the word   password, I get cnffjbeq  p=c, a=n, s=f, etc.

That's all there is to a substitute cipher. but what if we want to get trickier?  Let's mix it up a little

ABCDEFGHIJKLM
ZYXWVUTSRQPON

This is just the same except the letters are arranged a bit differently; the second half of the alphabet is backwards.

If I convert the word password using this I get kzhhdliw.   Hey that's just as mixed up as before, but this time the cipher key is not as obvious.

Let's take it one step further:

ABCDEFGHIJKLM
TUVWXYZNOPQRS

in this case, I broke the bottom line at the letter T.  I added all the letters from T-Z and then ran out, so I started with N again to finish out the bottom line and ended with S.

Definitely NOT as easy to break the cipher key.

Again, these ciphers can be used in any combination to create a strong password.

I would keep a copy of the cipher in your shoe (just kidding) wallet or purse to help you in the event you forget the password you created with it.