1, common key algorithm:

Key algorithms are used to encrypt sensitive data, abstracts, signatures and other information. Common key algorithms include:

DES (Data Encryption Standard): Data encryption standard, which is fast and suitable for encrypting a large amount of data; 3DES(Triple DES): Based on DES, a piece of data is encrypted three times with three different keys, which is more powerful;

RC2 and RC4: It is faster to encrypt a large amount of data with variable-length keys than DES;

Idea (International Data Encryption Algorithm) is an international data encryption algorithm, which uses 128 bit key to provide very strong security.

RSA: Invented by RSA Company, it is a public key algorithm that supports variable-length keys, and the fast length of the file to be encrypted is also variable.

DSA (Digital Signature Algorithm): Digital signature algorithm, which is a standard DSS (Digital Signature Standard);

AES(Advanced Encryption Standard): Advanced encryption standard, which is the next generation high-speed and high-security encryption algorithm standard. At present, one implementation of AES standard is Rijndael algorithm;

BLOWFISH, which uses a variable-length key, can reach 448 bits in length and runs very fast;

Other algorithms, such as ElGamal, Deffie-Hellman, new elliptic curve algorithm ECC, etc.

2. One-way hash algorithm:

One-way hash function is generally used to generate message digest, key encryption and so on. Common ones are:

MD5 (Message Digest Algorithm 5): It is a one-way hash algorithm developed by RSA Data Security Company. MD5 is widely used and can be used to encrypt data blocks with different lengths into 128-bit values.

SHA (Secure Hash Algorithm) is a relatively new hash algorithm, which can generate a value of 160 bits for data operations of any length.

MAC (Message Authentication Code): Message Authentication Code is a one-way function using a key, which can be used to authenticate files or messages on a system or between users. HMAC (key hash for message authentication) is an example of this function.

CRC (Cyclic Redundancy Check): Cyclic Redundancy Check. CRC check is widely used in various data check applications because of its simple implementation and strong error detection ability. It takes up less system resources and can be realized by software and hardware. It is a good means of data transmission error detection (CRC is not a hash algorithm in the strict sense, but its function is roughly the same as that of hash algorithm, so it belongs to this category).

3. Other data algorithms:

Other data algorithms include some commonly used coding algorithms and their conversion to plaintext (ASCII, Unicode, etc. ), such as Base 64, Quoted Printable, EBCDIC, etc.