Secure Method of Communication
Secure Method of Communication
Introduction...
In today's business world, your business competitors
will often try and get an edge over you by any means
possible.This includes attempts at intercepting your
sensitive business communications.
This is why it is highly recommended all companies,
including yours, buy secure communication equipment for
sensitive business communications.
The problem...
But what happens when you're out of the office,
you don't have your secure equipment with you ,
and yet you still urgently need to communicate
sensitive information with a colleague...?
The solution...
The solution is having an alternative method of communicating
securely by encoding your messages.
This system is called the one-time pad and is absolutely impossible to crack.
Even the biggest supercomputer of any one spy agency would not be able
to accomplish this feat.
The only things required are a pen and a paper.
Once encoded, you may send your messages by mail, email, or even by phone.
Let's get started.
The one-time pad method
Step 1: Create the
key...
The critical component of this system is the random key.
A key is a series of numbers that is used to take your original message
(the plaintext) and turn it into a coded message (the ciphertext).
Before creating a random key, you need a way to convert
alphabet characters into numbers.
Make a conversion table by taking a sheet of paper and writing letters and numbers as follow:
A
B
C
D
E
F
G
H
I
J
K
L
M
N
O
P
Q
R
S
T
U
V
W
X
Y
Z
01
02
03
04
05
06
07
08
09
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
You are now ready to create a key.
First, write down a series of random alphabet characters, such as
RTISEWVZQYHKOPBU.
Break this long string of letters into blocks of two characters each, as follow:
RT IS EW VZ QY HK OP BU
Using the conversion table we've created above, convert the characters into numbers.
For example R=18 and T=20, so the first block HL becomes 1820.
The result is 1820 0919 0523 2226 1725 0811 1516 0221
You have now created your first key.
(Make sure to create a key much longer than this so that you can
send several
messages before the key is used up.)
As you will use the block of numbers to encode your messages,
you will
cross out each block you have used as to not use it more than once.
(To simulate the crossing out of a block i will gray the blocks as follow:
1820 0919 0523 2226 1725 0811 1516 0221 )
Create two copies of your key.
One for you and the other for the recipient
of your messages.
Step 2: Format your message...
Let's use an example.
If the message you want to
encrypt is ACCEPT IT, you format this text message
into blocks of two characters each, yielding AC CE PT IT.
Next, convert the letters into numbers by using the conversion table above.
In this example, A=01, C=03, so the first block would be 0103.
The entire string becomes 0103 0305 1620 0920.
size=+2>Rules...
Rule 1-
Numbers.
Spell out numbers in full in your plaintext.
For example, 123 becomes ONE TWO THREE
Rule 2-The Period.
Use an X for each period in your plaintext.
For example, GOT YOUR MESSAGEX APPROVE TRANSACTIONX.
Rule 3-End of message.
Add XX at the end of your plaintext message
for termination.
Spies would add several bogus characters after the XX
to make it even more difficult for code breakers(those who tries to decode secret messages)
by making them try to decode
those meaningless characters after the XX.
Step 3:
Encode your message...
We need a way to tell the recipient where the key begins,
otherwise he won't be able to decode the message.
Remember in our earlier example, we created a key and stroked off (in gray) the blocks
we'd already used.Here's what our key looked like.
1820 0919 0523 2226 1725 0811 1516 0221
The starting position in the key is at block 0919.
So we will place the string 0919 at the beginning of our message
so the recipient will know how to decode.
The plaintext message of 0103 0305 1620 0920 becomes
0919 0103 0305 1620 0920
because we place the pointer 0919 at the beginning of the string.
We are now ready to encode our message.>
First we write out the plaintext.
Directly below it we write out the key.
Then we add the key to the plaintext using Fibonicci addition.
This means we do no carrying. For example, 9 + 2 would yield 1 not 11.
And 7 plus 6 would yield 3 not 13.
Here's how the agent's working sheet would look.
Plaintext
0919
0103
0305
1620
0920
Key
--
0523
2226
1725
0811
Ciphertext
0919
0626
2521
2345
0731
The encoded message is ready to be sent to
the intended recipient.
You now have a message that can absolutely not be cracked by anyone but the intended recipient.
Decoding the message...
To decode a message, simply reverse the calculations.
Subtract the key from the ciphertext using Fibonicci subtraction.
This means we allow no negative numbers. We add 10 if required.
For example, 1 - 9 would yield 2 (because we add 10 so that we're able to subtract 9 from 11).
The first block in the ciphertext tells our intended recipient where to start in the key.
Here's what the recipient's working sheet looks like.
Ciphertext
0919
0626
2521
2345
0731
Key
0919
0523
2226
1725
0811
Plaintext
--
0103
0305
1620
0920
Here's how we subtract 0523 from 0626.
The first column is 0 - 0 = 0.
The second column is 6 - 5 = 1.
The third column is 2 - 2 = 0.
The fourth column is 6 - 3 = 3.
(If your substraction look something like this: 1 - 6, it gives
1-6 = 5 because 11 - 6 = 5.)
By using the conversion tablet described earlier,
the recipient converts the string of numbers back into alphabet characters.
In this example, 01=A and 03=C, so the first block 0103 converts to AC.
The string 0103 0305 1620 0920 becomes AC CE PT IT.
The receiver reformats it to become ACCEPT IT.
Security measures...
If your key is kept to yourself and the intended recipient,
and no one else
ever gets access to it,
this system is 100% secure.
No one will ever break the code.
Period.
But you need to be careful about security.
Strong key security...means you must conceal your key in a location
where you'll know if it's been tampered with. Usually this means carrying it on yourself at all times.
Good disposal security...means shredding and/or burning your messages
and the keys when you are done with it.
One time and one time only...means you don't use a key more than once. Ever.
When used correctly, this system will enable you to share even the most sensitive
pieces of information with your colleagues over unsecured channels of communications
such as mail, email and even by phone.
Test your
skills...
To verify your new skills, try to decode the cyphertext
by using the key below.
the key:
color=#808080>0418 4678 1223 4104 0804 0123 6212 8840 7013
the ciphertext:
is 4104 1129 1028 6520 8360 8338
Remember that the first four-digit group in the ciphertext
is a pointer indicating where to begin in the key.
Max Penn
http://www.spy-equipment-buying-guide.com
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