Chapter 2109: One Person's Performance
"In fact, a one-way trapdoor function of exponential power operation is constructed, and the ciphertext C=M^emodn is obtained by calculating the plaintext M"
"However, it is difficult to reversely calculate the base M from the ciphertext C and the exponent e. Unless you know the trapdoor information d."
"..."
Eloquently, Martin Hellman narrates the essentials and details.
The expressions of everyone also changed from bewildered, to surprised, to suddenly enlightened.
There is a saying, a fool is only one teacher away from a genius...
When Martin Hellman led everyone into the gate, everyone suddenly felt enlightened.
It turns out that public key cryptography is not as difficult as imagined.
And the source of this difficulty comes from the threshold!
Yes is the threshold.
Every profession and every topic has a threshold.
There is an easy-to-understand term for this threshold, which is called "entry".
The people sitting here are all top talents from major universities or major research institutes.
The knowledge contained in their heads is enough to circle the earth twice.
The reason why they feel difficult in the face of public key cryptography is because they have not crossed the threshold!
Sometimes, it is actually very simple to solve a problem, all you need to do is catch the fleeting white dove.
It's just that it's extremely difficult to catch it.
And now, Martin Hellman sent the white pigeon to everyone.
Everyone has no reason to refuse...
On the stage, the corners of Martin Hellman's mouth were raised. Seeing everyone's suddenly enlightened expressions, a faint smile quietly hung on his face.
To be honest, he was very happy, very happy.
Because that's the nature of science.
This is the original intention of his invention of public key encryption technology.
He wants to make this technology known to more people and applied by more people.
The corner of Martin Hellman's mouth raised slightly, and he spoke slowly: "We talked about the algorithm structure just now, now let's talk about the addition and solution technology..."
"Encryption technology, as the name suggests, is to encrypt the program. [Encryption] c=m^emodn, RSA is a block cipher. For a certain n, the plaintext message is converted into binary data and divided into data groups smaller than n."
“[Deciphered] proves that:
c^dmodn=m
c^dmodn=(m^emodn)^dmodn
=(m^(ed)modn^d)modn
=m^(kΦ(n)+1)modn
"..."
=m^(kΦ(n))*mmodn (Fermat's little theorem Euler promotion)
=1*mmodn
=m"
Each group of ciphertext after decryption is the result of modulo n operation, so it is also a number smaller than n.However, the number of digits obtained by calculation for each group of ciphertext is indefinite.The n bits can be filled with 0's. "
"..."
quiet!
deathly quiet...
Listening to Martin Hellman talking on the podium, the venue was silent.
At this moment, a monstrous wave has already set off in their hearts.
They wanted to exclaim aloud.
But the only remaining examples tell them that they can't!
Because doing so is likely to disrupt Martin Hellman's thinking!
So they could only desperately suppress the huge waves in their hearts, forcefully put on a calm expression, and listened quietly to Martin Hellman's report.