ios-senior8-Network Advanced

I. Data security

Key: A key is a parameter that is entered in an algorithm that converts plaintext into ciphertext or converts cipher text to plaintext. The key is divided into a symmetric key and an asymmetric key (you can also divide the encryption key and decryption key according to the purpose)

plaintext : Information that is not encrypted to directly represent the meaning of the original text

Ciphertext : The information that is hidden from the original meaning after being encrypted

Encryption : The implementation process of converting plaintext to ciphertext

decryption : The implementation process of converting ciphertext to plaintext

Data Security : is an active containment measures, the security of the data itself must be based on a reliable encryption algorithm and security system, mainly symmetric algorithm and public key cryptosystem two (asymmetric algorithm), all contain the data encryption and decryption process

symmetric algorithms : Symmetric cipher algorithms are sometimes called traditional cryptographic algorithms, which means that the encryption key can be deduced from the decryption key, which in turn is established

Asymmetric algorithms : Symmetric cipher algorithms are sometimes called traditional cryptographic algorithms, that is, the encryption key can be deduced from the decryption key, in turn, also set up

There are many kinds of encryption algorithms, in iOS development, MD5 is our common digest algorithm

Two. MD5 encryption

Hashing algorithm: A unique and extremely compact numeric representation of a piece of data. The hash value of the data can verify the integrity of the data. Typically used for quick find and encryption algorithms

Typical hashing algorithms are: MD2,MD4,MD5, and SHA-1

Directly on the code

Three. Key string encryption

Directly on the code

Four. Public Key cryptography

(not finished)

Five. KVO

(not finished)

ios-senior8-Network Advanced