RSA signature, and examination of understanding signed
original programmers learn to death last released on 2019-03-24 17:41:37 reading number 376 collections
launched
a public key encryption
assumptions, I find two numbers, a is 1, one is 2. I love this number 2, on reservations, will not tell you (the private key), then I tell you, one of my public key.
I have a file, you can not let others see, I use an encrypted. Others found the file, but he did not know the private key to decrypt 2 is, ah, so he can not be untied, I can only use
the number 2, that is my private key to decrypt. So I can protect the data.
My good friend x 1 with my public key to encrypt a character a, encrypted became b, on the web. Others steal this file, but others can not be untied, because people do not know 2 is my private key,
only I can decrypt the decrypted after a. In this way, we can send the encrypted data.
Second, the private key signature
if I use the private key to encrypt a piece of data (of course, I can only use private key encryption, because only I know my private key 2), the results of all the people have seen my content, because they are I know
that I am the public key is 1, then what is the use of this encryption it?
But my friend said someone posing as x I gave him a letter. How to do it? I want to send me a letter, the content is c, 2 with my private key encryption, the encrypted content is d, sent to x, then told him
to decrypt see is not c. He used my public key to decrypt 1, and found that indeed is c.
This time, he will think, I can use the public key to decrypt the data, it must be added using my private key secret. I only knew I had a private key, so he can be sure that something really is my hair.
So that we can confirm the identity of the sender. This process is called digital signature. Of course, the specific procedure is slightly more complicated. With a private key to encrypt data, use a digital signature is.
Summary: The public and private keys are paired, they decrypt each other.
Public key encryption, private key to decrypt.
Private digital signature, public key authentication.
For example
Example, two users Alice and Bob, Alice wants to send some plaintext encryption key to Bob by a double technology, Bob has a public and private key, the encryption and decryption process is as follows:
Bob his public key to the Alice.
Alice her message encrypted with Bob's public key and then transmitted to Bob.
Bob uses his private key to decrypt Alice's message.
The above process can be represented by the following FIGS., Alice Bob using the public key encrypted, Bob decrypt with its private key.
And examples from the "secure network infrastructure and applications Standard Second Edition"
RSA algorithm
RSA public key encryption algorithm is the 1977 Ron Rivest, Adi Shamirh and LenAdleman in (MIT) developed. The name comes from the name RSA to develop their three. RSA is the most influential public key encryption algorithm, which is resistant to all known password attacks so far, it has been recommended as the ISO standard public-key data encryption. RSA algorithm is based on a very simple arithmetical fact: multiplying two large prime numbers is very easy, but then want to factorization of their product is extremely difficult, so it can be the product of the public as an encryption key.