Chapter 240 The French Doomsday (10)

"Your Highness."

Hedy Lamarr's voice was soft and sweet, as if it could make one's bones melt.

"Miss Hedy, how is the progress of the research project?" Wilhelm went straight to the point. If it were another man, he might start with some sweet words, trying to win the favor of the woman. However, with his current status, he could skip these steps. If he wanted, there would be a queue of women lining up to flatter him, and who knows, it might even circle the Earth.

Hedy smiled charmingly. "With the current progress, we should enter the practical stage by the end of the year."

"That's great." Wilhelm signaled to a nearby waiter, who brought a glass of champagne for Hedy. "So, starting from next year, our communication will become a black hole that enemies cannot eavesdrop on!" Compared to fixed-frequency communication, frequency hopping communication was more covert and difficult to intercept. As long as the other side was not aware of the frequency hopping pattern, it was challenging to intercept our communication content.

Hedy's expression became somewhat unnatural. "Your Highness, you also know that practicality doesn't mean widespread use. It might be a bit difficult to popularize it even at the army group level."

"..." Wilhelm sighed. "So, you mean we still have to use the Enigma cipher machine at the grassroots level."

Friends who have watched the American movie "U-571" know that the "Enigma" cipher machine was a top-secret device that the Allies tried their best to obtain during the war, and it was crucial to defeating the German Navy submarines. History indeed confirmed this. For submarine warfare, especially the German Navy's "wolfpack" tactics, radio communication was the most important means for submarines to operate at sea and obtain information. The "Enigma" cipher machine was the device that concerned the entire radio communication security. Its importance could be imagined.

The "Enigma" cipher machine, as shown in the movie, looked like a box filled with complex and delicate components, resembling a typewriter at first glance.

It used a polyalphabetic substitution encryption method, employing a keyboard, rotors, jumpers, reflectors, and a display for symmetric encryption/decryption. When you pressed any letter on the keyboard for the first time, the corresponding letter would be converted to another letter through the keyboard-rotor-jumper-reflector-display. For example, when you typed A for the first time, bulb B lit up, the rotor moved one position, and the letters corresponding to each letter changed. When you typed A again for the second time, the corresponding letter might become C; similarly, when you typed A for the third time, bulb D might light up. This was the key to the Enigma's difficulty in being decrypted—it was not a simple substitution cipher. The same letter in different positions in the plaintext could be replaced by different letters, and the same letter in different positions in the ciphertext could represent different letters in the plaintext. Frequency analysis was useless here. This encryption method was called a "polyalphabetic substitution cipher".

Enigma belonged to the category of encryption methods with algorithm and key separation. The difficulty of cracking Enigma lay in not knowing the current key, including the initial positions of the rotors and the jumper settings. In daily use, Enigma's configuration could be transmitted through methods such as codebooks, pre-agreements, and encrypting transmissions with the previous day's key.

The German military evaluated the use of the Enigma cipher machine and believed that it was easy to carry, easy to use, and, more importantly, highly secure. For the enemy, even if they had the Enigma machine, they still could not decrypt it without simultaneously possessing the keys formed by the three defense lines. Colonel Erich Fellgiebel, the Chief of Communications of the German Supreme Command, believed that the "Enigma" would be the perfect communication device for the German Armed Forces' blitzkrieg.

Therefore, from the German Supreme Command to the Army, Navy, and Air Force, the "Enigma" was widely used as the standard-issue cipher machine. The Germans had every reason to believe that they had mastered the world's most advanced and secure communication encryption system at that time—a code that was impossible to crack.

However, relying on machines with such blind trust would ultimately lead to the bitter consequences brought about by the machines.

The first to crack Enigma were the Poles. They managed to obtain a commercially used Enigma machine (usually used for commercial purposes but appropriated by the military—German confidence in their encryption technology was evident). Two Polish mathematicians led a team of assistants, and after several years of effort, they successfully deciphered 75% of the intelligence in Enigma cipher telegrams by the end of 1937.

However, the German military improved the Enigma by increasing the number of rotors to five. The Poles could not crack the new "Enigma" machine used by the Germans until the eve of the Second World War.

With foresight, the Polish intelligence knew that Poland was bound to be occupied. In order to resist this common cause with Germany, they decided to send their Enigma cipher machine, along with related research materials, to Britain and France, placing the hope of defeating Hitler on these two major European powers.

Britain attached great importance to the solution provided by Poland and even expanded its codebreaking team for information security.

They moved from Room 40 in the old codebreaking facility to Bletchley Park, increasing the area by tens of times. The staff, initially just over 20 people, expanded to over 9,000 five years later.

At the same time, there was a change in the structure of the employees. Previously dominated by linguists, the main force now was mathematicians. This was specifically instructed by the Poles—recruit a large number of mathematicians.

As everyone knows, Alan Turing, although he admired the intelligence of the Poles, realized that the Polish method of decryption overly relied on German vulnerabilities. Later, when the German military upgraded the Enigma machine, this method became ineffective. So, Turing pursued a more direct and violent decryption method: machine against machine. If the Poles used parasitic airborne assaults through enemy lines, Turing wanted something more like a head-on confrontation of an infantry division. The monstrous cipher created by the machine could only be defeated by another machine. The human task was merely to design the working principle of the machine and optimize the computational workload the machine had to perform.

On March 14, 1940, the first Turing "bomb" was put into use at Bletchley Park. Soon after, it successfully deciphered the first Enigma cipher intelligence. When Turing personally presented this intelligence to the Air Force Intelligence Director Winterbotham, he excitedly said, "From now on, the top-secret intelligence of the Germans is like a book that we can read."

The Enigma cipher gradually became the most lethal weapon in the hands of the British. In later decisive military actions such as the Battle of the Atlantic, the occupation of Sicily, and the Normandy landings, the British and the Allies gained the initiative on the battlefield by timely deciphering Enigma ciphers, tilting the balance gradually toward the Allies.

Wilhelm certainly wouldn't repeat such a foolish mistake. Although Alan Turing was currently in Germany, he couldn't guarantee that there wouldn't be other talents in Britain who could crack the Enigma cipher machine. Therefore, he sought ways to improve the Enigma machine and increase the difficulty of decryption.

Hedy asked, "Your Highness, does this count as completing the mission?"

Wilhelm smiled and said, "Of course, you've done a great job, and I won't break my word. However, the scenes in this movie will be grand, and it's impossible to start shooting at a time like this. We'll have to wait until the war is over."