1、MD5

MD5 is a common message digest algorithm, which is used to hash messages of any length to generate a unique value of 128 bits (16 bytes). It can quickly and safely compress data into irreversible fingerprint strings, and is often used for digital signature, password storage and tamper prevention. MD5 algorithm has the advantages of high efficiency, high speed and high security.

2、SHA 1

SHA- 1 is software based on Merkle-Damg? Hash algorithm of rd structure is a member of SHA algorithm family. SHA- 1 Generate 160 bit message digest based on 5 12 bit message block. Compared with MD5, SHA- 1 is more secure and reliable, with higher security and anti-collision, so it has gradually replaced MD5 as one of the most commonly used hash algorithms.

3、SHA256

SHA-256 is a kind of SHA-2 algorithm family, and it is a reliable hash algorithm. It uses 5 12 bits to process messages and generates a 256-bit message digest. Compared with SHA- 1, SHA-256 is superior in security and anti-collision, and is widely used in digital signature, certificate signature, file integrity check and other fields.

Scope of application of the algorithm:

Algorithm is an algorithm for generating text or data summary, which usually generates concise and representative summary information by compressing and refining the input text or data. The algorithm can automatically extract long articles, news reports, papers and other texts, extract the most important and key information, and help users quickly understand the theme and main points of the text.

In the process of database query, if the amount of data is huge, we can use the summarization algorithm to abstract the data in the database. By summarizing information, the speed and efficiency of database query can be accelerated. In large-scale data sets, there are a large number of duplicate files, which may lead to the waste of storage and the difficulty of data processing.

The algorithm can generate a unique file fingerprint or hash value, which can be used to judge whether the file is duplicate, so as to copy the file. The algorithm is widely used in data integrity verification and digital signature. By generating the summary information of the data, we can verify whether the data has been tampered with during transmission, and ensure the source and integrity of the data.