Therefore, this time the Prussians learned wisely, and no matter how many times this simple correspondence was made, it could not completely solve the problem, because people could always trace back to the source and find a one-to-one correspondence to determine the password. Pen ~ fun ~ pavilion www.biquge.info So, they figured out the adfgv box password. The box of this password is a 5*5 letter matrix, which is used to correspond to 26 English letters, what? You say only 25? That's easy.,Just let i and j correspond to the same letter.。

One of the very important reasons why it is called adfgv password is that the horizontal and vertical coordinates of this 5*5 column box are represented by these five letters. According to the letters in the plaintext, and then replace it with the horizontal and vertical coordinates of this box, this becomes the first step of encryption, in fact, this encryption method is very easy to crack, this is the simplest classical encryption method, but unfortunately, this time the Germans added the key! The so-called key is another shift encoding, when the key is shifted, an additional column is added to the original coordinate system with the key character, and then the ciphertext encrypted for the first time is written in the order of 5 lines, and then the key is transcribed according to another alphabetical order, so that the final ciphertext is formed.

The key to this kind of password is that the key and the shift password are changing every day, and it is useless if you find it in time, or you get the initial corresponding form of 5*5 is not meaningful, the other party can write a 5*5 form casually, it is possible to crack it, but if you use guessing, or simply find a one-to-one correspondence method, it is difficult to ensure timeliness and accuracy. What to do in the age of no computers?

There is only one way, and that is to look for telegrams with the same start, as this means that they use the same decomposition and shift keys, and then filter them mathematically. Of course, there is also an objective condition here, that is, there is a large enough amount of information to appear repeatedly, and there is enough material to decipher it, which is why the Bavarian intelligence team was not able to decipher the other side at the beginning. It's in the process of accumulating materials!

From the sixth week the whole thing began to take a turn for the worse, and on the 38th day after the game began, the prince handed over the first deciphered telegram to the Kaiser. Two days later came the second one. And then before the end of the week, 6 telegrams were sent to Berlin! This means that a full 120,000 marks have been transferred from the Kaiser's account to the prince's name. And when the seventh week came, in just one week, a whole 18 telegrams were deciphered! In less than two weeks, the Kaiser lost 500,000 marks!

"Can anyone tell me what's going on? Didn't I ask you to replace the chart and key? Why is the other party's decipherment speed still so fast? We send a telegram in the morning, and while I have afternoon tea, the Bavarian side will send me the plain text! I feel that our IQ is insulted, and the other party looks at us with a look that looks at us as a fool! This is our shame! The Empire has provided you and your so-called cryptographers with the best possible conditions with high budgets, and see what you have done? The Kaiser said angrily.

"It's now, it's the seventh week, and you can't even decipher a single telegram, and what about Bavaria? They have already deciphered 24 telegrams from us! No matter how much we change the box and key, we can't change this result, so I can only say that your method is a failure, and the encryption method you are proposing is not trustworthy at all! At this point, even the Kaiser, who had no research in cryptography, knew that he had lost, because the other party had adapted to this encryption method, and the space for this cipher to expand was too small, so no matter how much he changed it, he could not fail the fate.

"Theoretically, there will be enough changes in the 5*5 correspondence table, and we can increase the difficulty of deciphering by randomly changing the correspondence method, but the intelligence needs to be transmitted steadily, and the correspondence table itself cannot be changed at will, and one of our pieces of information may eventually be transmitted from the General Staff to a division-level commander, and if we want to change the correspondence table without authorization, it will be a very cumbersome process."

"And also because of the 5 * 5 comparison relationship, our shift password can only be 5 digits, the other party can find the breakthrough through enumeration and statistics, and then correspond to the facts, as long as you can find the key of one of the letters, then other information using the same key will have no confidentiality at all, we recognize the other party's ability to decipher, but I must say that the Kingdom of Bavaria is more talented in encryption, and they have made a new encryption method, This way we look at it is simply uncrackable! Because every phrase is different in every telegram! Schlieffen was convinced, he did not justify his failure, but clearly admitted it!

"So we're losing again?" An expression of disbelief appeared on the Kaiser's face, "But just now you said that the ciphertext of each phrase is different, which means that you have already identified some phrases, is that so?" ”

"Yes, the Bavarians are so confident in their cipher that they will even give us the correct answer after 3 days, and then we will reverse the ciphertext according to the plaintext given. But unfortunately, the alphabetical correspondence order of each of their ciphertext telegrams is chaotic, at least we can't see the pattern, and when we use the same key, the correspondence of the file is determined, even if we change the key every day, it still can't produce their effect. Schlieffen lost this time, but he was convinced.

"Well, well, well, we've failed again! Look at what kind of people our General Staff are made of! Finally, I'll give you another week. I hope you can at least see something. Although the Kaiser knew that Schlieffen was helpless when he said these words, he still did not want to give up.

"I'll do my best." Schlieffen said in a deep voice.

"Your Highness, if nothing else, His Majesty William should be overwhelmed, right?" At the same time, in Swan Castle, Count Schelling said to **** with a telegram that had just been deciphered today.

The end result was no surprise to the Prussians, who were helpless for ciphers that had never been repeated, whose correspondence was so deranged, that they could not be deciphered by any of the existing mathematical methods.

"Go to Bavaria and get the new way of ciphering passwords! I want to know where we lost! The Kaiser ordered.

The third is more present~~~! Ask for subscription, ask for tips~~~! (To be continued.) )