2. Application of encryption algorithm in HTTPS
Realization principle of 3.3. Message summary 5
Introduction:
The main feature of the message digest algorithm is that the encryption process does not need a key, and the encrypted data cannot be decrypted.
Features:
No matter how long the input message is, the length of the calculated message digest is always fixed.
Generally speaking, as long as the input messages are different, the summarized messages will be different, but the same input will produce the same output.
Application scenario:
Message digest algorithm is mainly used in the field of "digital signature" as a digest algorithm of plaintext.
Comparison:
They are all developed from MD4 and have many similarities in structure and strength.
Introduction:
Symmetric encryption refers to an encryption algorithm that uses the same key for encryption and decryption.
Features:
Symmetric encryption algorithm is characterized by open algorithm, small amount of calculation, high encryption speed and high encryption efficiency. The disadvantage is that both parties to the transaction use the same key, and the security cannot be guaranteed.
Application:
Encryption and anti-theft in data transmission
Comparison:
AES makes up for many shortcomings of DES, supports the lengthening of keys and packages, has higher security and very low memory requirements.
Introduction:
Asymmetric encryption algorithm needs two keys: public key and private key. The public key and the private key are a pair. If the data is encrypted with the public key, it can only be decrypted with the corresponding private key. Encrypted with a private key, only the corresponding public key can be decrypted.
Features:
The strength of the algorithm is complex, and the security depends on the algorithm and key. However, due to the complexity of its algorithm, the encryption and decryption speed is not as fast as that of symmetric encryption and decryption.
Application scenario:
Digital signature, key transmission encryption
Comparison:
With RSA, you can encrypt and sign key pairs. Using DH, only encryption, no signature mechanism.
Compared with RSA, ECC has absolute advantages in many aspects.