A common problem has always existed in all the ciphers that have come up in our discussions since ancient times. That is the fingerprint. No matter what is done, the information will be leaked due to this weakness in the cipher, and if you continue to manipulate it, the keynote will be retrieved at some point.
How to almost delete a cipher fingerprint? Suppose X used a big shifting in the letter and it is completely unbiased. You may be wondering, what is it like? Will X then take whatever number he wants?
Suppose that X had written one number after another from the numbers 1 to 26, about 100 numbers in a row. If he encrypts his letter with a list of these huge numbers, it will be seen that it is becoming very difficult to retrieve the original letter. However, this can be done better if Neetu does not do it himself and somehow gets his shifting numbers, which is more neutral.
None of us, however, think completely neutrally. If you were asked to think of a number, how much would you think? Maybe 8 or 11? Or 9? However, since your thinking is affected, if you are asked to write 100 or more consecutive numbers, each of which is between 1 and 26, you will find that certain numbers are repeated many times over. This is a very normal thing. Since our thinking is not completely neutral, our shifting string will not be uniform, it can be assumed. What is the way out of this problem? Sampling these numbers from something very simple, neutral.
We all played more or less ludu. In a ludu game, if the six is made in a neutral and correct manner, it can be seen that if the number of sixes is thrown many times, the result (Outcome) is equal to the number of times. This is a matter of general probability. More interestingly, it is not possible to predict what will happen if you throw a six while playing Ludu. The result of throwing a six is completely unaffected by anything else!
Then think, in a six there are only six numbers written on six sides. If we had a six in our hand that has a total of 26 faces, all the numbers from 1 to 26 are written in it. Then we would get 26 different fruits and these fruits would be completely neutral. It is not possible to predict who will come after whom or what the outcome may be. If such a six is thrown 100 times in a row, then a huge number of strings will be found. We can use it for shifting. How? Very straightforward, first of all the length of this shifting string can be made as big as you want, you can make it as small as you want. Then since its outcome does not depend on any individual, it is not possible to predict its outcome in any way. In addition, since all the results are neutral, the shifting string obtained in this case will show the encryption of the message, in which almost all the characters will repeat equally. In other words, there will be no benefit in this message even without frequency analysis. All letters are used in shifts and neutrally. Therefore, if encrypted, it can be seen that the frequency of the letters of the encrypted letter is almost balanced and there is almost no possibility of information leak from it. That is, the frequency of all the characters will be the same. But at the same time keep in mind that the strings we use for shifting should be neutral and balanced. So I don't have repetitive shifting in encryption in this way, that is, it is not possible to guess the nature of subsequent shifting in any way. Taking a large amount of data, it can be seen that the frequency of all the characters in the encrypted message will be equal.
The problem that we have been talking about for so long, the problem that was weakening all our encryption, has been solved.
This method of encryption using multiple strings is called the One Time Pad method. This is by far the most powerful type of encryption we see or use. The first practical results of this concept were seen in the late nineteenth century. Why is this encryption so powerful? Or why is it so hard to break? Let's take a look at the mathematical explanation behind this.
Caesar's cipher was basically shifting each character by the same number, shifting all the characters to a certain distance. In order to recover the original message, it is enough for us to try a maximum of 28 times. And if the fortune is good, the original money can be recovered before that. But the shifting of the one-time pad is different in each letter. Suppose we want to encrypt BANGLADESH. In this case, the total number of letters is 10. Shifting for each character can be anything between 1-26. So if we calculate the total possible result using the concept of assembly, the number would be more than 2610 or 1.4x1014. Can you imagine how big this number is?
I try to give a little idea, if you start writing all the possible options on a simple A-Four paper, the possible results on a piece of paper and keep stacking them one on top of the other, then the paper column that will be found will be the thickness of the earth. 1 / 12th of the distance from the sun. Imagine for a second you were asked to stand in front of a huge pile of paper and examine each piece of paper. Is this the only solution? What else do you have to do but stand stunned?
Roughly speaking, it is possible to decipher it, it is not realistic to check the accuracy of each with this huge amount of information. So this is the best way to maintain pure privacy. One-time pads are our most powerful weapon in maintaining that privacy.