Chapter 257 I hope some regrets will not happen again
The next day, Xie Jianye went to find Gao Zhendong at work. All the procedures were completed, so he could come and say hello to him.

Gao Zhendong was very surprised to learn that Lao Xie lived next door to him. This would make it more convenient for several comrades to get together and they could take care of each other.

"Captain Gao, to be honest, if it weren't for you, I wouldn't have been able to get this house."

This will make it difficult for Gao Zhendong to deal with it. He doesn't have that much face, right?

Xie Jianye smiled and said, "I think I've considered your safety a little bit."

Gao Zhendong suddenly realized that maybe this was really the meaning, but it didn’t matter. As long as he could bring good results to his comrades, it wouldn’t be a bad thing.

We should take care of each other and it is normal to ensure each other's safety.

He suddenly remembered something: "Old Xie, is it convenient for my sister-in-law to go to work? Is it far?" Xie Jianye is a little older than him.

Xie Jianye smiled and said, "It will probably take about an hour to walk there, but it doesn't matter. Having a house is much better than squeezing into their dormitory."

After that, she leaned close to Gao Zhendong's ear and said mysteriously, "We are planning to have a baby, and this place is definitely better than their dormitory."

Gao Zhendong laughed: "Congratulations. But an hour is a bit far, it's not convenient for my sister-in-law to go to work. Do you have a bicycle?"

Xie Jianye shook his head: "Still saving up industrial tickets."

It was quite difficult for him to get a bicycle ticket at one time. Fortunately, industrial coupons could be used instead of bicycle tickets. However, the current regulations in the capital required fifteen industrial coupons to be equivalent to one bicycle ticket.

When Gao Zhendong heard this, he thought it was a coincidence. He had received a lot of these things when he got married, including gifts from the leaders of the 17th Ministry of Machine Building and his master, as well as rewards from the factory. He couldn't spend any of them.

He reached into his bag and actually took something out of the storage room: "How much is missing? I'll make it up for you."

This made Xie Jianye feel embarrassed. Platoon Leader Gao had helped so much, but now he had to pay for the industrial tickets. He could not accept it no matter what.

But before he could say anything, he saw what Gao Zhendong had in his hand and felt that it was possible to take it, because Gao Zhendong had so many industrial tickets in his hand, such a huge amount!
It seems that Zhendong really doesn't lack this thing.

It’s really inconvenient for my wife to not have a bicycle, and there are also safety issues when she gets off work late.

Grit your teeth and be a little thick-skinned. We came from the same tunnel, so there's no need to be so distant with each other. Some things just need to be remembered in your heart.

"Then I won't be polite to you. I'm short of ten."

Gao Zhendong took out twenty of them and said, "Use the rest to buy a sewing machine for my sister-in-law. Just consider it as my congratulations on your new home, haha."

Xie Jianye took it and said, "Okay, thanks. By the way, speaking of this, when will you two return to the courtyard?"

Gao Zhendong thought for a moment and said, "Maybe tomorrow. I heard that the construction was completed today. Let the materials inside dry and go back tomorrow."

Xie Jianye smiled and said, "That's perfect. Let's take advantage of today and tomorrow to clean up the house. Tomorrow's dinner can be eaten at my house. Invite Big Lao Wang as well. Just think of it as a gathering for me to move."

After Xie Jianye left, Gao Zhendong continued his work. The single crystal furnace was being prepared for completion. According to Yu Yuncheng, they were now confident that they could pull out silicon single crystals that met the requirements. They were preparing for formal tests, such as hot field roasting and so on, and they would try to make the test conditions the best before starting work.

Gao Zhendong agreed with this, saying that slow work produces fine work and sharpening the knife does not delay the chopping of wood.

However, before that, some test records, reports, analyses, etc. needed Gao Zhendong to review and sign one by one, so he put aside other things in his hands and worked on this first.

Fortunately, the DJS-59 specially approved by the th Ministry of Machine Building was immediately installed and put into use at home. In this way, he no longer needed to do a considerable part of the operating system programming work in the factory, and the allocation of working time became more flexible.

Oh my god, the people from the 12th Ministry of Machine Building are finding ways to ask me to work overtime, right?

Gao Zhendong complained while working.

At the same time, several people in the Defense Work Committee were doing something.

They made a super long phone call, and the other end of the line was deep in the desert.

However, there was no one on the phone, only the light on the modem was flashing.

Ten minutes later, the scientists in the desert looked at the encrypted file they had sent and that was sent back by the Defense Work Committee and laughed, "It's really fast. Let's decrypt it and see if they are the same."

After a while, the file was decrypted successfully and was exactly the same as the plaintext before encryption.

The scientists present were extremely excited: "This is great. With this, we can directly transmit some of our important data, documents, and reports through the confidential telephone. Even if others get them, it will be useless."

One scientist asked another: "You are an applied mathematician. What do you think of the encryption strength of this thing?"

This scientist is an expert at calculating missile aerodynamics, but after getting the DJS-59, his work became even easier.

He thought for a moment and said cautiously, "I haven't seen the algorithm for this thing, but judging from the key length, the encryption strength is very high given the current computer capabilities. But if computers develop rapidly, it's hard to say."

It must be said that the expert is an expert. He was able to deduce the situation of DES by looking at the key length. Several scientists present discussed: "Should we mention this to the National Defense Committee? It is good to be prepared for a rainy day."

"Well, that makes sense. After all, this matter cannot be taken lightly."

The same applied mathematics master gave his analysis: "In my opinion, from a mathematical point of view, the author of this algorithm should be able to improve the encryption strength, but the current algorithm may be the result of a compromise between encryption strength and encryption and decryption speed."

Another scientist smiled and said, "If that's the case, then it's easy. What we want is encryption strength, but we don't have high requirements for encryption and decryption speed. As for the encryption and decryption speed just now, even if it takes ten or eight times longer, it's actually acceptable."

The person in charge of the desert side made the decision: "Then we will contact the Defense Work Committee immediately and tell them about this situation to see if we can improve the encryption strength. We don't care about speed."

This request was immediately fed back to the Defense Work Committee, and the leaders of the Defense Work Committee attached great importance to this matter.

In fact, he also organized relevant mathematicians to analyze Gao Zhendong's GM-1 encryption algorithm. Under the current environment, it is indeed very difficult to crack it by brute force, but Da Mo's idea is not unreasonable. What if computers have been greatly developed?

His solution to this problem was to find someone to help him. To untie the bell, one had to find the person who tied it, so he went to find Gao Zhendong.

There was no need to leave this matter overnight. Immediately, the Defense Work Committee called Gao Zhendong. Gao Zhendong put down the work on the single crystal furnace and rushed over. Anyway, the single crystal furnace was not that urgent.

He rushed to the Defense Work Committee and heard the requirement for the encryption algorithm, but he was not told where the requirement came from.

However, Gao Zhendong could guess a little bit, it was nothing more than those few places, especially there was no requirement for encryption speed, but there were very high requirements for encryption strength, so there were even fewer.

Gao Zhendong smiled and said, "This is easy."

In addition to the leaders of the Defense Work Committee, there were also programmers responsible for rewriting the encryption and decryption programs.

Gao Zhendong directly brought out 3DES, but he made some changes. He did not limit it to 3 times, but changed it.

"Just use the GM-1 algorithm, but perform multiple encryption and decryption."

"Is it that simple?" Programmers always feel that this seems too confusing.

Gao Zhendong nodded: "It's that simple, but the specific order is a bit special."

"First, the encryption and decryption keys must be different each time. Each time you encrypt, you need to change the key. For example, if you encrypt three times, the total length of the key is 21 bytes, and 7 bytes are used each time."

The mathematics personnel at the scene thought for a while and nodded in affirmation: "Well, Director Gao's method is good. In fact, it uses the existing algorithm to directly increase the length of the key."

The programmer was confused: "This will only extend the brute force cracking time to three times the original time. There is no qualitative change."

The mathematician laughed and said, "No, no, no, according to this algorithm, the increase in time is exponential, not linear."

The programmer still couldn't figure it out for a while, but since professional mathematicians said so, it seemed like there was no problem.

Seeing that they understood his idea, Gao Zhendong made a second request: "No matter how many times the encryption is performed, the GM-1 encryption algorithm should be used for encryption for odd-numbered times and the GM-1 decryption algorithm should be used for encryption for even-numbered times. Moreover, the total number of encryptions should be an odd number."

"To put it simply, the first time you encrypt, you use the GM-1 encryption algorithm. The second time you encrypt, you use the GM-1 decryption algorithm. The third time you encrypt, you use the encryption algorithm again. And so on."

Taking three encryption as an example, the whole process is to encrypt with Key3 - decrypt with Key1 (actually also encrypt) - encrypt with Key2.

This sentence is a bit difficult to understand, but everyone can still understand the requirement, because the decryption algorithm of GM-1 is actually also an encryption operation, but it is the inverse operation of the encryption algorithm.

In other words, encryption was actually performed three times, but no one could figure out the purpose of Gao Zhendong's request.

Gao Zhendong smiled and said, "We can call this algorithm the multi-channel GM-1 algorithm. This rule is used to maintain compatibility with the single-channel GM-1 algorithm."

Everyone present was lost in thought, feeling a little confused.

The first people to react this time were programmers, after all, compatibility is their professional area.

"Ah, I see. In this way, when the key used each time is the same, the encryption result of multi-channel GM-1 is the same as that of single-channel GM-1!!"

Now everyone understood and praised Gao Zhendong's rule as very clever.

The entire multi-channel GM-1 algorithm is very clever. By using multi-channel encryption, the encryption strength can be greatly improved by arbitrarily adjusting the number of encryptions. At the same time, the decryption algorithm is cleverly used for encryption in even-numbered encryptions, solving the compatibility problem between single-channel encryption and multi-channel encryption.

After understanding Gao Zhendong's meaning, the leader of the Defense Work Committee immediately made the decision: "Do it!"

Gao Zhendong, who had just left the National Defense Working Committee, was extremely happy about the result. He no longer had to fly thousands of miles to deliver some confidential documents, and some accidents might not have happened.

Although the development and popularization of DJS-59 by myself has certainly greatly changed the progress and process of the desert project, and some regrets should not happen again, it is always a good thing to have an extra layer of insurance.

(End of this chapter)